[Federal Register Volume 64, Number 222 (Thursday, November 18, 1999)]
[Proposed Rules]
[Pages 63140-63157]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-29758]



[[Page 63139]]

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Part III





Department of Transportation





_______________________________________________________________________



Federal Aviation Administration



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14 CFR Parts 91, 121, and 125



Revisions to Digital Flight Data Recorder Regulations for Boeing 737 
Airplanes and for Part 125 Operations; Proposed Rule

  Federal Register / Vol. 64, No. 222 / Thursday, November 18, 1999 / 
Proposed Rules  

[[Page 63140]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 91, 121, and 125

[Docket No. FAA-1999-6482; Notice No. 99-19]
RIN 2120-AG87


Revisions to Digital Flight Data Recorder Regulations for Boeing 
737 Airplanes and for Part 125 Operations

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to amend the digital flight data recorder 
(DFDR) regulations for transport category airplanes to add a 
requirement for all Boeing 737 (B-737) series airplanes to record 
additional flight data parameters. This proposal is based on safety 
recommendations issued by the National Transportation Safety Board 
(NTSB) following the investigations of two accidents and other 
incidents involving B-737 aircraft. The additional parameters that 
would be recorded would provide the only currently available means of 
gathering information that the FAA and the NTSB anticipate will help 
assess the reasons for continuing incidents that appear related to 
rudder anomalies on B-737 airplanes. In addition, the FAA is proposing 
a change to the flight data recorder requirements of part 125 that 
would affect all aircraft operated under that part or under deviation 
from that part.

DATES: Comments must be received on or before December 20, 1999.

ADDRESSES: Comments on this document should be mailed or delivered, in 
duplicate, to: U.S. Department of Transportation Dockets, Docket No. 
[FAA-1999-6482], 400 Seventh Street SW., Room Plaza 401, Washington, DC 
20590. Comments also may be sent electronically to the following 
Internet address: [email protected]. Comments may be filed and 
examined in Room Plaza 401 between 10 a.m. and 5 p.m. weekdays, except 
Federal holidays.

FOR FURTHER INFORMATION CONTACT: George Kaseote, Aircraft Certification 
Service, AIR-130, Federal Aviation Administration, 800 Independence 
Avenue SW., Washington, DC 20591; telephone (202) 267-8541; facsimile 
(202) 493-5173.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed action by submitting such written data, views, or arguments as 
they may desire. Comments relating to the environmental, energy, 
federalism, or economic impact that might result from adopting the 
proposals in this document also are invited. Substantive comments 
should be accompanied by cost estimates. Comments must identify the 
regulatory docket or notice number and be submitted in duplicate to the 
DOT Rules Docket address specified above.
    All comments received, as well as a report summarizing each 
substantive public contact with FAA personnel concerning this proposed 
rulemaking, will be filed in the docket. The docket is available for 
public inspection before and after the comment closing date.
    All comments received on or before the closing date will be 
considered by the Administrator before taking action on this proposed 
rulemaking. Comments filed late will be considered as far as possible 
without incurring expense or delay. The proposals in this document may 
be changed in light of the comments received.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this document must include a pre-addressed, 
stamped postcard with those comments on which the following statement 
is made: ``Comments to Docket No. FAA-1999-6482.'' The postcard will be 
date stamped and mailed to the commenter.

Availability of NPRMs

    An electronic copy of this document may be downloaded using a modem 
and suitable communications software from the FAA regulations section 
of the FedWorld electronic bulletin board service (telephone: (703) 
321-3339) and the Government Printing Office (GPO)'s electronic 
bulletin board service (telephone: (202) 512-1661).
    Internet users may reach the FAA's web page at http://www.faa.gov/
avr/arm/nprm/nprm.htm or the GPO's web page at http://
www.access.gpo.gov/nara for access to recently published rulemaking 
documents.
    Any person may obtain a copy of this document by submitting a 
request to the Federal Aviation Administration, Office of Rulemaking, 
ARM-1, 800 Independence Avenue SW., Washington, DC 20591, or by calling 
(202) 267-9680. Communications must identify the notice number or 
docket number of this NPRM.
    Persons interested in being placed on the mailing list for future 
rulemaking documents should request from the above office a copy of 
Advisory Circular No. 11-2A, Notice of Proposed Rulemaking Distribution 
System, which describes the application procedure.

Background

Statement of the Problem

    Two aviation accidents in the United States involving Boeing 737 
(B-737) model airplanes appear to have been caused by a rudder hardover 
with resultant roll and sudden descent: United Airlines (United) flight 
585, near Colorado Springs, Colorado, on March 3, 1991, and USAir 
flight 427, near Aliquippa, Pennsylvania, on September 8, 1994. The 
NTSB has determined that the rudder on B-737 airplanes may experience 
sudden uncommanded movement or movement opposite the pilot's input, 
which may cause the airplane to roll suddenly. Incidents of suspected 
uncommanded rudder movement continue to be reported, including five 
incidents in 1999 involving U.S.-registered airplanes.1
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    \1\ On February 23, 1999, a USAirways Metrojet B-737-200 
experience a roll to the left with no change in heading. This 
incident is further described later in this NPRM. On February 23, 
1999, A USAirways B-737-200 experienced an uncommanded rudder 
movement shortly after departure. On March 12, 1999, a Delta Air 
Lines B-737-247 experienced a 2-second uncommanded yaw to the right 
during cruise flight. On April 13, 1999, a United B-737-300 
experienced an uncommanded 20 to 30 degree roll to the left during 
level cruise flight described as a ``sharp quick uncommanded kick to 
the left.'' On April 10, 1999, a United B-737-300 aborted its 
takeoff roll because of an uncommanded yaw event as the airplane 
passed through 120 to 130 knots.
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    The B-737 airplanes involved in the United and USAir accidents and 
in the recent rudder incidents were equipped with the required flight 
data recorders (FDRs), but none of the recorders provided information 
about the airplanes' movement about their three axes or the positions 
of the flight control surfaces immediately preceding the accidents or 
incidents. To date, corrective measures taken to resolve the suspected 
problem have been limited by the lack of data being recorded. More data 
is needed to help identify events occurring during suspected 
uncommanded or hardover rudder events.
    The FAA has issued 17 airworthiness directives (ADs) for the B-737 
airplane as a result of the investigation into the USAir accident, 
including one that addresses an upgraded rudder power control unit 
(PCU) designed to remedy one element of the rudder upset problem, a 
rudder reversal. Suspected rudder upsets continue to occur, however, 
and some of the B-737 airplanes that recently experienced

[[Page 63141]]

suspected uncommanded rudder movements (not reversals) had been 
modified with the upgraded rudder PCU, suggesting that other events are 
still occurring in the rudder system.
    The FAA agrees with the NTSB's conclusion that the collection of 
additional rudder system and flight control data are necessary to more 
effectively assess the cause of the continued uncommanded rudder 
movements and to possibly design a solution. The NTSB stated in its 
safety recommendations that all B-737 airplanes should record pitch 
trim, trailing and leading edge flaps, thrust reverser position, yaw 
damper command, yaw damper status (on/off), standby rudder status (on/
off), and control wheel, control column, and rudder pedal forces.

Summary of B-737 Accidents

United Flight 585

    On March 3, 1991, United flight 585, a B-737-291, was on a 
scheduled passenger flight from Denver to Colorado Springs, Colorado. 
As the airplane was completing its turn to final approach, it rolled 
rapidly to the right and pitched down, reaching a nearly vertical 
attitude before it struck the ground. The airplane was destroyed and 
none of the 5 crewmembers or 20 passengers survived. The FDR recorded 
five flight data parameters (altitude, airspeed, heading, vertical 
acceleration, and microphone keying) in accordance with the applicable 
regulations for an airplane its age. The FDR was not required to record 
other parameters that the NTSB later perceived as critical to its 
accident investigation, including airplane pitch and roll attitude, 
engine thrust, lateral and longitudinal acceleration, control wheel 
position, rudder pedal position, and the position of the control 
surfaces (rudder, aileron, and spoiler). The NTSB was unable to make a 
determination of the probable cause of the accident.

USAir Flight 427

    On September 8, 1994, USAir flight 427, a B-737-3B7, was on a 
scheduled passenger flight from Chicago, Illinois, to Pittsburgh, 
Pennsylvania, when, during the approach to Pittsburgh, the airplane 
suddenly rolled to the left and pitched down until it reached a nearly 
vertical attitude and struck the ground near Aliquippa, Pennsylvania. 
The airplane was destroyed and none of the 5 crewmembers or 127 
passengers survived. The FDR was equipped to record the following 13 
parameters: altitude, airspeed, heading, pitch attitude, roll attitude, 
vertical acceleration, longitudinal acceleration, microphone keying, 
low pressure compressor speed, high pressure compressor speed, exhaust 
gas temperature, fuel flow, and control column position.

NTSB Investigation of USAir Flight 427

    Early in the investigation of the USAir accident, the NTSB noticed 
that the airplane experienced a high rate of change in its heading, an 
indication that the initial upset of the airplane may have been caused 
by uncommanded rudder movement. This situation had been considered in 
the 1991 United flight 585 accident investigation, and the NTSB 
reviewed the information it had collected from the United accident as 
the USAir investigation continued. Another rudder upset incident 
occurred on an Eastwind Airlines2 B-737 while the USAir 
investigation continued, and a concurrent investigation was opened. The 
Eastwind investigation concluded that unlike the B-737s involved in the 
United and USAir accidents, the Eastwind flight was moving at well over 
the crossover airspeed,3 and thus maintained sufficient roll 
control authority to overcome the effects of full rudder deflection.
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    \2\ On June 9, 1996, Eastwind fight 517, a B-737-2H5, was on a 
regularly scheduled passenger flight from Trenton, New Jersey, to 
Richmond, Virginia. While on approach to Richmond, the airplane 
yawed abruptly to the right and then rolled to the right. The 
captain immediately applied opposite rudder and left aileron. The 
yaw/roll event slowed but the airplane was still attempting to roll 
so the captain advanced the right throttle to compensate for the 
roll with differential power. The airplane then appeared to move 
back toward neutral for 1 or 2 seconds before abruptly returning to 
a right bank. The flightcrew then disengaged the yaw damper system 
and several seconds later the upset event stopped. The airplane flew 
normally for the remainder of the flight. There were no injuries to 
the 48 passengers or 5 crewmembers nor any damage to the airplane. 
The FDR recorded the following 11 parameters: time, altitude, 
airspeed, magnetic heading, engine pressure ratio (both engines), 
microphone keying, roll attitude, control column position, and 
longitudinal and vertical acceleration.
    \3\ The crossover airspeed is the airspeed above which the 
lateral control system (ailerons) of the B-737 can overcome the 
aerodynamic forces caused by a rudder that has gone to a full 
hardover position (full travel in one direction).
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FAA Actions

    Following piloted computer simulations of the USAir accident and 
reports of malfunctions in the yaw damper system of B-737s, the FAA 
issued two ADs requiring design changes to the rudder system on B-737 
airplanes. To address possible rudder hardover scenarios and 
uncommanded yaw damper movements, the FAA first issued AD 97-14-03 (62 
FR 34623, June 27, 1997). That AD requires installation of a newly 
designed rudder-limiting device to reduce rudder authority at flight 
conditions where full rudder authority is not required; and 
installation of a newly designed yaw damper system to improve system 
reliability and fault monitoring capability. In response to the 
possibility of a secondary slide jam and rudder reversal, the FAA next 
issued AD 97-14-04 (62 FR 35068, June 30, 1997), which requires 
installation of a new vernier control rod bolt and a new main rudder 
PCU servo valve. The new servo valve is similar to the servo valve used 
on B-737 Next Generation (NG) series airplanes (B-737-600, -700, -800, 
and -900) and is designed to eliminate the possibility of a rudder 
reversal.

Incident Investigation: 1991-1995

    The NTSB investigated 28 B-737 incidents involving anomalous rudder 
activity or uncommanded rolls between 1991 and 1995. Because all of the 
airplanes involved were manufactured before May 26, 1989, under 
Sec. 121.343(b) they were required to record only five parameters of 
flight data. As a result, the NTSB lacked certain definitive 
investigative criteria and had little more than the flightcrews' 
subjective recollections to aid in determining a probable cause.

Safety Recommendations: 1995-1997

    Between 1995 and 1997, while investigating the USAir accident, the 
NTSB issued 20 safety recommendations dealing with the B-737; three of 
those (A-95-25, A-95-26, and A-95-27) dealt specifically with upgrades 
to the FDR for all B-737s. The NTSB stated that if either the United or 
the USAir B-737 airplanes had recorded data on the flight control 
surface positions, flight control inputs, and lateral acceleration, 
that information would have allowed quick identification of any 
abnormal control surface movements and configuration changes or 
autopilot status changes that may have been involved in the loss of 
control.

FAA Response: 1997 Regulations

    In response to these safety recommendations, the FAA promulgated 
revisions to the DFDR requirements for all airplanes. (Revisions to 
Digital Flight Data Recorder Rules; Final Rule (62 FR 38362, July 17, 
1997)) The revised DFDR regulations prescribe a maximum of 88 
parameters to be recorded on flight data recorders, with the exact 
number of parameters required to be recorded depending on the date of 
airplane manufacture. For turbine-powered

[[Page 63142]]

transport category airplanes manufactured on or before October 11, 
1991, and not equipped with a flight data acquisition unit (FDAU),\4\ 
14 CFR 121.344 and 125.226 require the recordation of 18 specified 
parameters by August 20, 2001. For airplanes manufactured on or before 
October 11, 1991, that were equipped with a FDAU, the regulations 
require the recordation of 22 parameters by August 20, 2001. Airplanes 
manufactured after October 11, 1991, are required to record 34 
parameters by August 20, 2001. In some situations, compliance may 
require the addition of sensors and wiring capable of recording the 
specified parameters or a reprogramming of the current recorder to 
accommodate the specified parameters. The 1997 DFDR regulations also 
added a requirement for newly manufactured airplanes. Airplanes 
manufactured after August 18, 2000, are required to record 57 
parameters, and airplanes manufactured after August 19, 2002, are 
required to record 88 parameters of flight data.
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    \4\ The flight data acquisition unit (FDAU) is an electronic 
device that acquires data from sensors of various types (analog, 
digital, pneumatic, etc.), translates the data into a digital 
format, and transmits the data to the flight data recorder.
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Further NTSB Findings

    On March 24, 1999, the NTSB issued the final report of its 
investigation into the crash of USAir flight 427. The NTSB determined 
that the probable cause of the accident was a loss of control resulting 
from the movement of the rudder surface position to its blowdown 
limit.\5\ Furthermore, the NTSB stated that--

    \5\ The rudder's blowdown limit is the maximum rudder deflection 
available for an airplane at a given flight condition/configuration 
and occurs when the aerodynamic forces acting on the rudder become 
equal to the output force of the rudder's powered control actuator, 
which is a function of the system hydraulic pressure.

the rudder surface most likely deflected in a direction opposite to 
that commanded by the pilots as a result of a jam of the main rudder 
PCU servo valve secondary slide to the servo valve housing offset 
from its neutral position and overtravel of the primary slide.

Continuing Concerns

    On February 23, 1999, USAirways Metrojet flight 2710, a B-737-2B7, 
experienced an unexplained rudder hardover at cruise altitude. The 
flightcrew reported that the airplane began to roll to the left 
although the heading did not change. After the flightcrew disconnected 
the autopilot, they noticed the right rudder pedal was forward of 
neutral and that pressure on the left rudder pedal would not move the 
rudder. The flightcrew regained normal rudder control only after the 
standby rudder system was activated under prescribed USAirways' 
procedures. The airplane made a successful emergency landing. The 
preliminary results of kinematic analysis and computer simulations 
using the Metrojet's FDR data indicate that the rudder traveled slowly 
to its blowdown limit. To date, examinations of the Metrojet rudder 
system have not revealed evidence of a failure or a jam of the servo 
valve or other problem, such as a blockage in the rudder system 
feedback loop, that would explain the uncommanded rudder hardover.
    The NTSB recognized that the B-737 airplane has flown over 92 
million hours since its initial certification in December 1967, and 
that the airplane's accident rate is comparable to that of other 
airplanes of a similar type. Nonetheless, the NTSB has concluded that 
the redesigned rudder system does not eliminate the possibility of 
other potential failure modes and malfunctions.

NTSB Recommendations

    The NTSB concluded in its March 1999 report that the current 
regulations for upgrading the DFDRs on existing airplanes are 
inadequate because they do not require the recordation of specific 
flight control information. Because several B-737 airplane rudder-
related events have been associated with the yaw damper system (which 
moves the rudder independent of flightcrew input), the NTSB concluded 
that it is important that yaw damper command (proposed parameter 90), 
yaw damper status (proposed parameter 89), standby rudder status 
(proposed parameter 91), and control wheel, control column, and rudder 
pedal forces (current parameter 88) all be recorded on all B-737 
airplanes. The NTSB also indicated that for optimal documentation, the 
indicated parameters need to be sampled more frequently than is 
currently required. The NTSB stated that by documenting the yaw 
damper's operation and the resultant rudder surface movements, a yaw 
damper event could be distinguished quickly from a flightcrew input or 
a rudder anomaly. The NTSB considers this information critical in the 
case of B-737 airplanes. The NTSB stated that if pilot flight control 
input forces had been recorded on the United, USAir, or Eastwind FDRs, 
the NTSB investigations would have been resolved more promptly and 
actions taken to prevent similar events would have been hastened.
    On April 16, 1999, the NTSB submitted the following recommendations 
to the FAA regarding the recordation of additional parameters on B-737 
DFDRs:
    Recommendation No. A-99-28. Require that all B-737 airplanes 
operated under part 121 or part 125 that currently have a FDAU be 
equipped, by July 31, 2000, with a flight data recorder system that 
records, at a minimum, the parameters required by the 1997 DFDR 
regulations applicable to that airplane, plus the following parameters: 
pitch trim, trailing edge flaps, leading edge flaps, thrust reverser 
position (each engine), yaw damper command, yaw damper status, standby 
rudder status, and control wheel, control column, and rudder pedal 
forces. Yaw damper command, yaw damper status, and control wheel, 
control column, and rudder pedal forces should be sampled at a minimum 
rate of twice per second.
    Recommendation No. A-99-29. Require that all B-737 airplanes 
operated under part 121 or part 125 that are not equipped with a FDAU 
be equipped, at the earliest time practicable, but no later than August 
1, 2001, with a flight data recorder system that records, at a minimum, 
the same parameters noted in Safety Recommendation No. A-99-28.
    The NTSB also noted in its final report on the USAir accident that 
B-737 flightcrews continue to report anomalous rudder behavior and the 
NTSB considers it possible that another catastrophic event related to 
the B-737 rudder upset could occur.

FAA Response

    The FAA agrees with the intent of NTSB Safety Recommendation Nos. 
A-99-28 and A-99-29. The agency shares the concern of the NTSB 
regarding continuing reports of rudder-related incidents on B-737 
airplanes and has initiated this rulemaking action.

The Proposed Regulations

    The FAA is proposing that all B-737 model airplanes be required to 
record the parameters listed in Sec. 121.344(a)(1) through (a)(22), and 
(a)(88), plus three new parameters, to be designated as (a)(89) through 
(a)(91), that would be added by this rulemaking. The new parameters 
include yaw damper status, yaw damper command, and standby rudder 
status. In addition, the sampling rate for the control forces listed in 
current paragraph (a)(88) would be increased for B-737 airplanes.

Compliance Date Determinations

    In its recommendation, the NTSB proposed that B-737 aircraft with 
FDAUs be retrofitted to record the listed parameters by July 31, 2000, 
and those

[[Page 63143]]

without FDAUs be retrofitted by August 1, 2001.
    The FAA is proposing dates of August 18, 2000, and August 20, 2001, 
respectively. The FAA notes that the compliance date for the 1997 DFDR 
requirements is August 20, 2001. In an effort to streamline compliance 
and facilitate planning by operators with mixed fleets, the dates in 
this proposed regulation are the same (or comparable to) the date in 
the 1997 regulations. These dates represent a change of less than three 
weeks from the date recommended by the NTSB. The FAA has determined 
that this brief delay is warranted in order to facilitate consistency 
and efficiency in the regulations.
    The FAA is aware that operators that have already upgraded their 
airplanes to meet the 1997 regulations may have incurred out-of-service 
costs from the additional downtime needed for installation. The FAA 
does not have data indicating how many airplanes may already have been 
retrofitted and thus would have to undergo another unscheduled 
maintenance visit to comply with these proposed regulations. 
Accordingly, the FAA is willing to consider an extension of the 
compliance period, up to one year beyond the 2001 compliance date, for 
those airplanes that installed a FDAU between July 16, 1996, and 
November 18, 1999. The FAA seeks comment from those operators who would 
benefit from such an extension, including specific information 
regarding the number of airplanes that would be affected by this change 
and the costs savings that would result from decreased downtime, as 
opposed to complying by August 20, 2001. The FAA understands that 
airplanes may have recently undergone an extended heavy maintenance 
visit to install equipment to meet the 1997 regulations, and seeks to 
mitigate the impact of this proposed rule if the savings would be 
significant without undermining the intent of the regulations proposed 
here. More detailed economic data is necessary to justify this further 
extension.

Compliance Status Determination

    The NTSB recommendations concerning the date for retrofit of B-737 
airplanes is based on whether the airplane was equipped with a FDAU as 
of the date of its recommendation, April 16, 1999. The 1997 DFDR 
regulations use the date July 16, 1996 (the date of the NPRM for those 
regulations), as the date for determining whether an airplane was 
equipped with a FDAU. The FAA has determined that the 1996 date is more 
appropriate for the requirements proposed here. The FAA is aware that 
some operators, in an attempt to comply with the 1997 DFDR regulations 
early, have already retrofitted B-737s in their fleets and have 
installed FDAUs in airplanes that were not equipped with them in July 
1996. Because airplanes with FDAUs would have to comply with these 
proposed regulations 1 year earlier than non-FDAU airplanes, these 
operators would be penalized by their early compliance with the 1997 
DFDR upgrades. Accordingly, the FAA has determined that it is more 
appropriate to use the July 16, 1996, date in this proposed regulation. 
That date already is familiar to operators, will facilitate consistent 
planning by affected operators, and will not penalize those operators 
that chose to complete the 1997 DFDR upgrades before they were required 
to do so.
    In addition, as proposed above, the FAA is considering extending 
the compliance date an additional year for those airplanes that were 
upgraded with FDAUs between July 16, 1996 and November 18, 1999.
    Accordingly, B-737 airplanes that were equipped with a FDAU on July 
16, 1996, would be required to comply with the requirements proposed 
here by August 18, 2000. Those B-737 airplanes that were not equipped 
with a FDAU as of July 16, 1996, would have to comply by August 20, 
2001. If the FAA receives sufficient data supporting such a change, 
airplanes that were retrofitted to include a FDAU between July 16, 
1996, and November 18, 1999, would have to comply by August 19, 2002.

Proposed Rule Changes

    The FAA is concerned that the promulgation of new regulations 
applicable only to B-737 airplanes may cause confusion since they 
overlap the DFDR upgrade regulations promulgated in 1997 for all 
airplanes operated under part 121 and part 125.
    Proposed changes to the affected sections of part 121 are 
summarized as follows:
    Paragraph 121.344(b) applies to airplanes that were manufactured 
before October 11, 1991, and requires the recordation of either 18 or 
22 parameters of flight data, depending on whether the airplane had a 
FDAU on July 16, 1996. Paragraph (b) would be amended by adding 
language that excepts B-737 airplanes from this paragraph; all B-737 
airplanes would instead be subject to the requirements listed in new 
paragraph 121.344(m), discussed below.
    Paragraph 121.344(c) applies to airplanes that were manufactured 
before October 11, 1991, and were equipped with digital data buses and 
certain FDAU equipment as of July 16, 1996. That paragraph requires the 
recordation of 22 parameters of flight data. Paragraph (c) would be 
amended by adding the same exception language for the B-737 that was 
proposed for paragraph (b). All B-737 airplanes would instead be 
subject to the requirements listed in new paragraph 121.344(m), 
discussed below.
    Paragraph 121.344(d) applies to airplanes that were manufactured 
after October 11, 1991. That paragraph requires the recordation of 34 
parameters of flight data, plus all other parameters that the airplane 
is equipped to record. Language would be added to paragraph (d) 
indicating that in addition to the requirements of (d), all B-737 
airplanes must comply with paragraph 121.344(m). Because the 
requirements of paragraphs (d) and (m) do not overlap completely, 
compliance with both would be required. The compliance dates for the 
two paragraphs remain separate. Essentially, a B-737 airplane covered 
by paragraphs (d) and (m) would have to install the parameters listed 
in paragraphs (a)(1) through (a)(22), plus paragraphs (a)(88) through 
(a)(91) by August 18, 2000, since they already have FDAUs. The 
parameters listed in paragraphs (a)(23) through (a)(34) would not have 
to be installed before August 20, 2001, under the requirements of 
paragraph (d). This is the only category of B-737s for which a dual 
compliance date would exist. The FAA anticipates that most operators of 
B-737s would choose to install all of the required equipment at the 
same time.
    Paragraph 121.344(e) applies to airplanes that will be manufactured 
after August 18, 2000. Paragraph (e) requires the recordation of 57 
parameters of flight data, plus all other parameters that the airplane 
is equipped to record. Similar to paragraph (d), language would be 
added to paragraph (e) indicating that in addition to the requirements 
of (e), all B-737 airplanes must comply with paragraph 121.344(m). 
Because the requirements of paragraphs (e) and (m) do not overlap 
completely, compliance with both would be required. In order to comply 
with both paragraphs, a B-737 airplane manufactured after August 18, 
2000, must go into service recording the parameters listed in 
paragraphs (a)(1) through (a)(57) and (a)(88) through (a)(91), plus all 
other parameters that the airplane is equipped to record.
    Paragraph 121.344(f) applies to airplanes that will be manufactured 
after August 19, 2002. That paragraph requires the recordation of 88

[[Page 63144]]

parameters of flight data, plus all others parameters that the airplane 
is equipped to record. Similar to paragraph (e), language would be 
added to paragraph (f) indicating that in addition to the requirements 
of paragraph (f), all B-737 airplanes must comply with paragraph 
121.344(m). Because the requirements of paragraphs (f) and (m) do not 
overlap completely, compliance with both would be required. In order to 
comply with both paragraphs, a B-737 airplane manufactured after August 
19, 2002, must go into service recording the parameters listed in 
paragraphs (a)(1) through (a)(91), plus all other parameters that the 
airplane is equipped to record.
    All paragraphs of current Sec. 121.344 not specifically amended by 
this rulemaking would continue to apply to all B-737 airplanes.

New Paragraph 121.344(m)

    The proposed rule contains a new paragraph 121.344(m) that would 
apply to all B-737 airplanes operated under part 121. The parameters 
required to be recorded under paragraph (m) would be either an 
alternative or an addition to the other recording requirements of 
Sec. 121.344 for an airplane of a particular age and having particular 
equipment installed, as explained above.
    The introductory text of proposed paragraph (m) states that all B-
737 airplanes must record the parameters listed in paragraphs (a)(1) 
through (a)(22) and (a)(88) through (a)(91) in accordance with the 
ranges, accuracies, resolutions, and recording intervals specified in 
appendix M to part 121. This language introduces two requirements that 
were not included in the 1997 DFDR upgrade regulations.
    First, under the 1997 DFDR regulations, B-737 airplanes that were 
not equipped with FDAUs did not have to have FDAUs installed to meet 
those regulations. However, the FAA anticipates that FDAUs will, in 
many cases, be necessary in order to meet the recording requirements 
established in paragraph (m) and appendix M.6 Second, B-737 
airplanes that were covered under Sec. 121.344(b) had to record the 
designated parameters in accordance with the rates, ranges, and 
accuracies specified in appendix B to part 121. Under this proposal, 
those airplanes would have to record the parameters listed in paragraph 
(m) in accordance with appendix M rather than appendix B. Appendix M 
contains more stringent requirements than appendix B for recording 
rates and accuracies, and may require equipment upgrades.
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    \6\ If an operator chooses instead to add a second flight data 
recorder, a FDAU may not be necessary because sufficient recording 
capacity would exist.
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    The proposed compliance dates for the requirements of paragraph (m) 
are in given in paragraphs (m)(1) and (m)(2). Paragraph (m)(1) provides 
that all B-737 model airplanes equipped with a FDAU of any type as of 
July 16, 1996, must comply with the requirements of paragraph (m) by 
August 18, 2000. Paragraph (m)(1) also provides that B-737 airplanes 
manufactured after July 16, 1996, must comply with the requirements of 
paragraph (m) by August 18, 2000. Without the manufacturing date 
provision, airplanes manufactured after the date specified (July 16, 
1996) would have no specified compliance date. This requirement 
presumes that B-737s manufactured after July 16, 1996, are equipped 
with FDAUs and thus would be subject to the August 18, 2000, compliance 
date.
    Paragraph (m)(2) states that all B-737 model airplanes that were 
not equipped with a FDAU of any type as of July 16, 1996, must comply 
with the requirements of paragraph (m) by August 20, 2001.

FDAU Equipment

    A FDAU is an electronic device that acquires data from sensors of 
various types, translates the data into a digital format, and transmits 
the data to a flight recorder. The FAA has received numerous questions 
regarding the meaning of a ``FDAU of any type,'' as used in the 
regulations. In some cases, operators have sought to delay compliance 
with the 1997 DFDR regulations or change the applicability of the 
regulations based on the equipment installed in their airplanes. The 
term FDAU is intended to refer to any piece of equipment installed on 
an airplane that functions as a data acquisition unit. A particular 
piece of equipment need not have a nameplate designating it as, or be 
marketed or sold as, a ``flight data acquisition unit'' in order to be 
considered a FDAU for purposes of these regulations if it functions as 
described. Further, a combination unit that is capable of FDAU 
functions would be considered a FDAU for purposes of both current and 
proposed regulations.

Compliance Dates

    With some minor variation, as described above, the FAA has agreed 
to the compliance schedule recommended by the NTSB for retrofit of B-
737s to record the flight data proposed in this rulemaking. The FAA 
agrees with the NTSB that operators have less to accomplish in a 
retrofit of airplanes that had FDAUs installed as of July 16, 1996, 
than they do for airplanes that have never had FDAUs. Accordingly, a B-
737 that had a FDAU installed on July 16, 1996, must comply with the 
requirements of paragraph (m) by August 18, 2000. A B-737 airplane that 
did not have a FDAU installed as of July 16, 1996, and does not have a 
FDAU installed as of the date of this NPRM must comply with the 
requirements of paragraph (m) by August 20, 2001. A B-737 airplane not 
equipped with a FDAU on July 16, 1996, but equipped with a FDAU as of 
the date of this NPRM, must comply with paragraph (m) by August 19, 
2002.
    The reasons for the change to the NTSB's recommended dates for 
compliance and for determining FDAU status were discussed above.

The New Parameters

Flight Control Input Forces

    The parameter listed in paragraph (a)(88) is described as ``[a]ll 
cockpit flight control input forces (control wheel, control column, 
rudder pedal).'' These control input forces are the center of the 
NTSB's recommendation and comprise data that the NTSB has stated is 
critical to a more complete investigation of accidents and incidents 
concerning loss of control of airplanes.
    This parameter was added in the 1997 amendment to the DFDR 
regulations, but within the last few months has become a source of 
disagreement as to where these forces must be measured. The FAA has 
received inquiries from the NTSB and Boeing concerning an acceptable 
means of recording rudder pedal forces. These are discussed below.

Actions by Boeing

    In 1996, in response to the proposed DFDR upgrade regulations, 
Boeing began to develop the equipment and instructions necessary to 
comply with paragraph (a)(88). In designing a rudder pedal force 
transducer (a specific type of sensor), Boeing's primary concern was to 
identify whether the input was coming from the forward or the aft end 
of the system; that is, whether the input was coming from the cockpit 
or the rudder assembly itself.
    Boeing developed a transducer that is placed ``midstream'' in the 
rudder control system. This specific transducer and its location were 
driven by the need for the equipment to be retrofitted or installed (on 
the assembly line) on every design in the Boeing fleet. Boeing's 
research indicated that a force transducer placed on the rudder pedals 
themselves could require significant structural redesign of existing 
airplanes.

[[Page 63145]]

Finally, Boeing was looking for a design and installation that it could 
develop quickly to meet the needs of operators for compliance with the 
1997 DFDR regulations, and that would require the least amount of 
structural disassembly to install.
    The first rudder force transducer was designed for the B-737 NG 
series airplanes. Although the NPRM for the 1997 regulations (published 
in July 1996) drove the initial design and timing, Boeing realized that 
whatever design it settled on would have to work on all of its airplane 
models.
    Boeing currently has available two service bulletins addressing the 
installation of the rudder force transducer on in-service B-737s. The 
service bulletin for the B-737-300, -400, and -500 series was released 
April 15, 1999; the bulletin for the B-737-600, -700, and -800 series 
was released May 20, 1999. The bulletin for the B-737-100 and -200 
series airplanes is in development. In mid-June 1999, Boeing reported 
that it had approximately 1,000 rudder transducer retrofit kits 
available, and that for the time being, they were being offered free of 
charge in order to encourage installation. Boeing stated that few kits 
had been requested at that time.

NTSB Opinion

    The NTSB's April 1999 recommendation indicated only that it wanted 
the control forces recorded, without specifying a means for doing so. 
In conversations with NTSB staff in May 1999, it became evident to the 
FAA that the NTSB would prefer a system that measured the rudder input 
force at the pedals themselves, an addition of four transducers rather 
than the one already designed by Boeing. Subsequent discussions between 
the FAA and the NTSB indicated that the Board is of the opinion that 
only the installation of four rudder pedal force sensors would meet the 
intent of its April 16, 1999, recommendation to record rudder input 
force.

FAA Response

    In response to the NTSB's expressed preference, the FAA requested 
that Boeing estimate the amount of time and cost involved in placing 
force sensors on each of the four rudder pedals of all B-737 airplanes. 
By letter dated May 26, 1999, Boeing estimated that it would take 
approximately 18 to 24 months to develop a service bulletin for the 
installation of four rudder pedal force transducers. In addition, 
Boeing estimates that it would take an additional 6 months before 
retrofit kits to install the transducers would be available.
    Boeing also indicated that it does not currently have a viable 
design solution for the four rudder pedal transducer option that does 
not involve ``major under floor structural modification,'' that would 
affect the entire fleet of B-737 airplanes. In conversations with 
Boeing staff, it was thought that as little as one inch of clearance 
was available under the rudder pedals, and that additional equipment 
installed at that location could require that one of the floor beams be 
moved. Boeing was not immediately able to indicate the estimated costs 
of such a modification, but the description implies that the cost would 
be substantial.
    The time estimated by Boeing to reengineer the B-737 for four 
rudder pedal transducers is well beyond the installation dates 
recommended by the NTSB. Moreover, the fact that the four rudder pedal 
transducer option might require significant redesign of the airplane 
structure suggests that the cost of such a modification would be 
extraordinary.
    In a presentation to the FAA and the NTSB in May 1999, Boeing 
indicated that the rudder transducer data, alone or in combination with 
other flight recorder data, will satisfy almost all of the concerns 
expressed by the NTSB for flight control data. The FAA acknowledges 
that choices have to be made when deciding what equipment is feasible 
for installation and the level of data that can be provided by 
different installations.
    The FAA acknowledges that there is a difference in the exact nature 
of the data acquired using Boeing's approved single transducer system 
and the NTSB's preferred four-pedal sensor retrofit. However, without a 
better understanding of the incremental benefits the particular data 
that the four-pedal sensor option would provide and a better estimate 
of the time and cost that would be required for installation, the FAA 
cannot decide which option provides the most overall benefit.
    The FAA specifically requests comment on the necessity and 
feasibility of instrumenting all four rudder pedals on B-737 airplanes 
with force sensors as a means of compliance with paragraph (a)(88). 
While the FAA has found Boeing's single force transducer to be 
acceptable for monitoring rudder pedal force, it requests comment on 
whether this should remain an accepted means of compliance for all B-
737 airplanes that have not yet installed the single transducer or 
otherwise complied with paragraph (a)(88).
    If the FAA finds, in light of the comments received, that the four-
pedal sensor retrofit is the only way available to determine the source 
of suspected uncommanded rudder movement, and that any incremental 
increase in cost and time required to accomplish this retrofit will 
provide a justifiable benefit, the FAA will propose it as an 
alternative for B-737 airplanes that have not otherwise complied with 
paragraph (a)(88) as of November 18, 1999. Any proposal would include 
an analysis of the costs and benefits of that configuration.
    The FAA notes that for the purpose of determining an estimated cost 
of these proposed regulations, the data for the single Boeing 
transducer was used for compliance with paragraph (a)(88) because it 
was the only information available. Those estimates are presented in 
detail in the regulatory evaluation section of this document. The FAA 
requests cost data for the four-pedal retrofit, described above, in 
order to determine whether the incremental increase in benefits that 
would be provided by that configuration are offset by the additional 
time and cost that would be needed for compliance.

Measuring Other Control Forces

    Paragraph (a)(88) also requires the measurement and recordation of 
control wheel and control column input forces. While these two 
measurements have not received the level of attention focused on rudder 
pedal forces, the FAA understands that there are issues of acceptable 
means of measuring these forces as well. The FAA specifically requests 
comment on the means and costs of measuring these control forces under 
the requirements proposed in this rulemaking.

Change to Current Parameter 88

    The NTSB also recommended that control input forces be measured 
more frequently for B-737 airplanes. This recommendation is being 
proposed as a change to the sampling interval that would apply to the 
B-737 only, and would require that control forces be sampled twice per 
second. This requirement would be added in appendix M, parameter 88, by 
means of a footnote specifying a shorter interval for B-737 airplanes 
only. The sampling interval for that parameter would remain unchanged 
for all other aircraft. Similarly, the text in the ``Remarks'' column 
for parameter 88 would remain applicable to other aircraft, but would 
not apply to B-737 airplanes.

[[Page 63146]]

Yaw Damper Status

    Proposed paragraph (a)(89) would add the recordation of yaw damper 
status. The intent of this requirement is to record whether the yaw 
damper is on or off. As described previously, the yaw damper system 
moves the rudder independent of flightcrew input, and has become a 
concern in the continuing occurrence of rudder-related incidents.

Yaw Damper Command

    Proposed paragraph (a)(90) would add the recordation of yaw damper 
command. The intent of this is to record the amount of voltage being 
received by the yaw damper system, which determines how much rudder 
movement is being commanded. This is an automatic system that is not 
controlled by cockpit commands, except to turn the system on or off. 
The flightcrew does not necessarily know what the system is doing since 
the rudder movement does not feed back through the rudder pedals.

Standby Rudder Status

    Proposed paragraph (a)(91) would add the recordation of standby 
rudder status. The standby rudder system is an alternative source of 
hydraulic power to the rudder that is used when primary hydraulic power 
is lost. The intent of this requirement is to record whether the 
standby rudder system switch is in the on or off position.

Changes to Part 125

    The changes proposed for part 121 are also proposed for the 
corresponding sections of part 125. Specifically, the changes made to 
Sec. 121.344 also would be made to Sec. 125.226. The changes made to 
appendix M to part 121 would also be made to appendix E to part 125.
    One additional change would be made to part 125. The FAA has 
determined that for purposes of flight data recordation, there is no 
difference between a large airplane operated under part 121 and one 
operated under part 125, or operated under part 91 under deviation 
authority from part 125. Accordingly, the FAA has determined that 
aircraft that are operating under deviation authority from part 125 
must still comply with the flight data recorder requirements of part 
125 for the particular aircraft. This requirement would apply to all 
aircraft, not just the B-737.
    This requirement is proposed as a new paragraph 125.3(d), which 
indicates that no deviation authority from the flight data recorder 
requirements would be granted, and that any previously issued deviation 
from the FDR requirements of part 125 would no longer be valid. Section 
91.609 also will be amended to reflect this requirement.
    Any person who operates under deviation authority from part 125 
would be subject to the FDR requirements of part 125 applicable to the 
particular aircraft as of the date of the final rule adopting these 
proposed regulations. For B-737s, compliance would be required as 
described in this proposed rule. For all other aircraft, compliance 
would be required as specified in the applicable subsections of 
Secs. 125.225 or 125.226. An aircraft subject to Sec. 125.226 would 
have to upgrade its FDR system to meet the requirements of that 
paragraph by the date specified in the applicable paragraph of that 
regulation.
    For persons operating using deviation authority from part 125, this 
would be a retrofit requirement, and no current holders of letters of 
deviation would be ``grandfathered.'' This NPRM serves as notice to 
current holders of letters of deviation that their deviation authority 
would be amended pursuant to paragraph 125.3(b).
    The FAA specifically requests comments addressing why the flight 
data recorder requirements of part 125 should not be made applicable to 
aircraft operated under deviation authority. The FAA also specifically 
requests comments from affected persons operating their aircraft under 
deviation authority from part 125 concerning the compliance dates 
proposed above. If the proposed compliance dates cannot be met, reasons 
why they cannot be met and acceptable alternatives should be submitted 
as part of the comment.

                                   Table 1.--Rule Changes and Compliance Dates
----------------------------------------------------------------------------------------------------------------
                                                           Number of                               Number of
                                   Manufacture date/      parameters           1997 rule          parameters
     Current rule paragraph         FDAU status in      required in the     compliance date     proposed for B-
                                         1996              1997 rule                                 737s
----------------------------------------------------------------------------------------------------------------
121.344(b)......................  Before 1991/no      18................  8/1999 through 8/   26 by 8/2001, FDAU
                                   FDAU.                                   2001.               necessary.
121.344(b)......................  Before 1991/FDAU..  22................  8/1999 through 8/   26 by 8/2000.
                                                                           2001.
121.344(c)......................  Before 1991/FDAU    22 plus any         8/2001............  26 by 8/2000.
                                   plus data bus.      capable.
121.344(d)......................  After 1991/with     34 plus any         8/2001............  38 by 8/2000.
                                   FDAU.               capable.
121.344(e)......................  After 2000/with     57 plus any         8/2000............  61 at manufacture.
                                   FDAU.               capable.
121.344(f)......................  After 2002/with     88................  8/2002............  91 at manufacture.
                                   FDAU.
----------------------------------------------------------------------------------------------------------------

Paperwork Reduction Act

    This proposal contains information collection requirements. As 
required by the Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)), 
the Department of Transportation has submitted the information 
collection requirements associated with this proposal to the Office of 
Management and Budget for its review.
    Title: Revisions to Digital Flight Data Recorder Regulations for 
Boeing 737 Airplanes and for Part 125 Operations.
    This notice proposes to amend the regulations to add a requirement 
for all B-737 series airplanes to record additional flight data 
parameters. The additional parameters to be recorded are not required 
by the current regulations and would provide the only currently 
available means of gathering information that the FAA and the NTSB 
anticipate will help assess the cause of continuing incidents that 
appear to be related to rudder anomalies on B'737 airplanes.
    The respondents are all U.S. certificate holders operating B'737 
airplanes under parts 91, 121, 125, and 129.
    The required information is electronically recorded on the FDR each 
time the airplane begins its takeoff roll until it has completed its 
landing roll and must be kept until the airplane has been operated for 
25 hours. The recorded data are overwritten on a continuing basis and 
are only accessed following an accident. This requirement is a nominal 
addition to a passive information collection activity and therefore 
does not contain a measurable hour burden. However, for purposes of the 
submission to OMB, the FAA has assigned a one hour burden to the 
request. The measurable burden

[[Page 63147]]

associated with this NPRM is the cost to the respondents. The breakdown 
associated with the cost can be found in the regulatory evaluation 
summary below.
    The agency is soliciting comments to: (1) Evaluate whether the 
proposed collection of information is necessary for the proper 
performance of the functions of the agency, including whether the 
information will have practical utility; (2) evaluate the accuracy of 
the agency's estimate of the burden; (3) enhance the quality, utility, 
and clarity of the information to be collected; and (4) minimize the 
burden of the collection of information on those who are to respond, 
including through the use of appropriate automated, electronic, 
mechanical, or other technological collection techniques or other forms 
of information technology (for example, permitting electronic 
submission of responses).
    Individuals and organizations may submit comments on the 
information collection requirement by December 20, 1999, to the address 
listed in the ADDRESSES section of this document.
    According to the regulations implementing the Paperwork Reduction 
Act of 1995 (5 CFR 1320.8(b)(2)(vi)), an agency may not conduct or 
sponsor, and a person is not required to respond to, a collection of 
information unless an agency displays a current valid OMB control 
number. The OMB control number for this information collection will be 
published in the Federal Register after it is approved by the Office of 
Management and Budget. It should be noted that OMB approval for the 
activity described above would be for a modification of the existing 
collection of information for digital flight data recorders under OMB 
control number 2120-0616.

Compatibility With ICAO Standards

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation, it is FAA policy to comply with 
International Civil Aviation Organization (ICAO) Standards and 
Recommended Practices to the maximum extent practicable. The FAA 
determined that there are no ICAO Standards and Recommended Practices 
that correspond to these proposed regulations.

Regulatory Evaluation

    Proposed changes to Federal regulations must undergo several 
economic analyses. First, Executive Order 12866 directs that each 
Federal agency shall propose or adopt a regulation only upon a reasoned 
determination that the benefits of the intended regulation justify its 
costs. Second, the Regulatory Flexibility Act of 1980 requires agencies 
to analyze the economic impact of regulatory changes on small entities. 
Third, the Office of Management and Budget directs agencies to assess 
the effects of regulatory changes on international trade. Fourth, the 
Unfunded Mandates Reform Act of 1995 (Public Law 104-4) requires 
agencies to prepare a written assessment of the costs, benefits, and 
other effects of proposed or final rules that include a Federal mandate 
likely to result in the expenditure by State, local, or tribal 
governments, in the aggregate, or by the private sector, of $100 
million or more annually (adjusted for inflation). In conducting these 
analyses, the FAA has determined that this proposed rulemaking: (1) 
Would be a ``significant regulatory action'' as defined in Executive 
Order 12866 or as defined in DOT's Regulatory Policies and Procedures; 
(2) would have a significant economic impact on a substantial number of 
small entities; (3) would have minimal effects on international trade; 
and (4) would not contain a significant intergovernmental mandate but 
would contain a significant private sector mandate. These analyses, 
contained in the document Initial Regulatory Evaluation of the 
Revisions to Digital Flight Data Recorder Rules for Boeing 737 
Airplanes and for Part 125 Operations, which has been placed in the 
docket, are summarized as follows.

Request for Comments

    The FAA requests comments on any and all of its assumptions, 
methodology, and data used in its economic analyses. The FAA also 
requests that commenters provide supporting data for their comments.

Data Sources

    The principal means of obtaining data for this analysis has been 
discussions with representatives from Boeing, several airlines that 
operate Boeing 737s, manufacturers of FDRs and FDAUs, and repair 
stations that would perform FDR system retrofits. In addition, the Air 
Transport Association surveyed its members and provided the FAA with 
data concerning potential compliance costs and out-of-service time that 
would be associated with the proposed rule. As may be expected, there 
were some differences in the various estimates. In choosing among these 
estimates, the FAA has generally selected the median estimates.

Affected Industries

    The FAA has estimated that the proposed rule would require that 
1,306 U.S.-registered B-737s have their FDR systems retrofitted to 
record additional flight data parameters. It would further require 
these additional flight data parameters to be recorded in an estimated 
2,144 newly manufactured U.S.-registered B-737s during the 20 years 
following the promulgation of the proposed rule. Twenty-four U.S. air 
carriers, 3 foreign U.S. air carriers, and 16 non-air carrier private 
owners currently operate U.S.-registered B-737s. The proposed rule 
would also affect transport category airplanes other than B-737s that 
are operating under part 91 on a deviation authority from part 125. 
However, as those costs and benefits for this latter group were 
included in the regulatory evaluation for the FAA's 1997 Digital Flight 
Data Recorder Rulemaking, they are not again evaluated in this proposed 
rule. Finally, the proposed rule would affect Boeing's future 
production B-737s.

Benefits

    The principal benefit from increasing the number of flight data 
parameters recorded would be the increased probability that a future B-
737 accident or incident investigation would uncover a previously 
unknown cause that would not have been discovered in the absence of 
these additional parameters being recorded. The discovery of this 
cause, in turn, could lead to corrective actions (for example, an 
airplane design modification or changes in operating procedures) that 
would help to prevent similar accidents. As there have been few B-737 
accidents whose causes could not be determined (two such accidents in 
about 92 million B-737 flight hours), the FAA has evaluated the 
benefits and costs of the proposed rule over a 20-year time period.
    In order to quantify the potential benefits of a prevented B-737 
accident, the FAA has used the following values: $2.7 million for each 
prevented fatality and an average of 96 passengers and crew on a B-737, 
for a resulting total of $259.2 million per airplane; $20 million for a 
destroyed B-737; $5 million for ancillary damage to ground structures; 
and $31 million for the resultant government and industry accident 
investigation. Thus, the average potential benefit from preventing a B-
737 in-flight accident would be about $315.2 million.

Compliance Costs

Summary

    B-737 operators would incur nearly all of the costs imposed by the 
proposed rule. These costs would be comprised of both one-time first-
year costs and

[[Page 63148]]

recurring annual costs. As described in the following paragraphs, the 
FAA has estimated that the present value of the total costs of 
compliance with the proposed rule would be about $205.3 million. Of 
that expenditure, about $158.6. million would be first-year costs to 
retrofit the current B-737 fleet that would be spent by August 20, 
2001. The present value of the increased costs of manufacturing future 
B-737s over the next 20 years would be about $40.4 million and the 
present value of the increased annual costs of additional fuel and 
maintenance of B-737s during the next 20 years would be $6.3 million.
    As previously discussed, the FAA revised the flight data recorder 
rules for many airplanes, including B-737s, in 1997. In the Final 
Regulatory Evaluation for that final rule, the FAA estimated at that 
time that the present value in 1997 of the costs to comply with those 
revision was about $48 million (which is equivalent to $58.8 million in 
year 2000 present value terms) for B-737 airplane operators and 
Boeing.7
---------------------------------------------------------------------------

    \7\ The present value of the total compliance costs for all 
airplanes affected by the 1997 revisions was estimated to be about 
$316.3 million (about $387.5 million in year 2000 present value 
terms).
---------------------------------------------------------------------------

    Consequently, if those revisions and this proposed rule are viewed 
as two parts of one rulemaking extended over time, the FAA has 
estimated that the present value of the overall compliance costs with 
these two parts would be about $264.1 million for the B-737 operators 
and for Boeing.
    The per-airplane retrofitting costs for only this proposed rule are 
have been summarized in Table 2 by B-737 series and by type of FDR 
system. As can be seen, the individual airplane costs can vary widely; 
the reasons underlying these differences are discussed in the following 
paragraphs.

                       Table 2.--Per-Airplane Compliance Cost by 737 Series and FDR System
----------------------------------------------------------------------------------------------------------------
                                                           Out-of-
            737 series              Equipment and labor    service     Out-of-service lost  Total costs and lost
                                           costs             days          net revenue           net revenue
----------------------------------------------------------------------------------------------------------------
200..............................     $160,200-$176,400          4-7             $250-$800     $160,450-$177,200
200--Advanced (No FDAU)..........       160,200-176,400          4-7           4,900-8,600       165,100-185,000
200--Advanced (FDAU).............         68,800-90,000          2-4           2,450-4,900         71,250-94,900
300 (No FDAU)....................       175,200-191,400          6-9         20,375-30,550       195,575-221,950
300 (FDAU).......................         35,100-90,000          2-4          6,800-21,550        41,900-111,550
400 (No FDAU)....................       160,200-176,400          6-9         17,350-30,350       177,550-206,750
400 (FDAU).......................         35,100-90,000          2-4          8,675-25,250        43,775-115,250
500 (No FDAU)....................       175,200-191,400          6-9         20,150-30,200       195,350-221,600
500 (FDAU).......................         35,100-90,000          2-4          6,700-19,100        41,800-109,100
600..............................                35,100          2-4         15,375-30,750         50,475-65,850
700..............................                35,100          2-4         17,350-34,675         52,450-69,775
800..............................                35,100          2-4         20,800-41,575         55,900-76,675
900..............................                35,100          2-4         21,950-43,875         57,050-78,975
----------------------------------------------------------------------------------------------------------------

    If the 1997 flight data recorder revisions and this proposed rule 
are viewed as two parts of one rulemaking extended over time, then the 
per B-737 compliance costs associated with the previous revisions need 
to be included. However, that Regulatory Evaluation did not 
disaggregate the compliance costs for individual B-737 series. As a 
result, the FAA has calculated in the Initial Regulatory Evaluation for 
this proposed rule that the per B-737 compliance costs associated with 
the 1997 revisions would be about $45,000.

One-time Compliance Costs to Retrofit B-737s

Types of One-time Compliance Costs
    The one-time first-year costs to retrofit B-737s would be: (1) The 
time to engineer new designs for the retrofitted FDR systems; (2) the 
equipment and labor costs to retrofit the FDR systems; and (3) the lost 
net revenue while the airplanes are out of service for a retrofit.
Time to Engineer New Designs for the Retrofitted FDR Systems
    There are two general types of engineering design costs associated 
with the proposed rule. The first type is the manufacturer's or 
airline's engineering time required to design the FDR system including 
the parts (that is, the FDR and the FDAU) to be used in a retrofitted 
B-737 FDR system. The second type is the engineering time required for 
the airline or repair station to obtain an FAA Supplemental Type 
Certificate (STC)/Parts Manufacturing Approval (PMA) for the revised 
FDR system.
    With respect to the FDR manufacturers' engineering costs, industry 
has reported that the increased number of recorded flight data 
parameters would require that a solid state FDR (installed to comply 
with the 1997 DFDR regulations) with a memory capacity of 64 words per 
second (wps) would need to be increased to 128 wps. This increase would 
involve a software change that would require FAA approval. The FAA has 
estimated that these one-time FDR engineering costs would be about 
$5,000 per airline per B-737 series. The FAA has further estimated that 
about 40 of these FDR approvals would be required, for a total one-time 
engineering cost of about $200,000 for the upgraded FDRs.
    Although the proposed rule would not specifically mandate a FDAU in 
every B-737, airline and repair station avionics engineers were 
unanimous in stating that retrofitting an airplane with a FDAU would be 
less expensive than retrofitting it with a second FDR system (and 
coordinating it with the first FDR system) to record the additional 
flight data parameters. Consequently, the FAA has assumed that an owner 
of a B-737 that does not have a FDAU would have the FDAU retrofitted in 
order to keep the airplane in service. Unlike upgrading FDR memory, 
installing a FDAU would be a substantial modification to the airplane 
and a FDAU manufacturer has estimated that obtaining FAA approval to 
integrate its FDAU in an FDR system would take between 16 and 26 weeks 
and would cost about $200,000 for each airline B-737 series/FDAU 
combination. However, the FAA has determined that after about five such 
approvals, a manufacturer could use commonality demonstrations to 
reduce this estimated time to between 8 and 12 weeks and reduce the 
estimated cost to about $25,000. It should be noted that several of 
these applications can be submitted at one time and the applicant would 
not wait for one airline's FDAU approval

[[Page 63149]]

before submitting the next airline's FDAU for approval. The FAA has 
estimated that about 40 of these FDAU approvals would be required, for 
a total one-time engineering cost of about $2.75 million for the FDAU 
approvals.
    With respect to airline or repair station engineering time to 
obtain an FDR system STC, its engineering staff would need to redesign 
the entire FDR system, ground test it, flight test it, and submit the 
drawings and data to the FAA. Airlines have reported that it would take 
anywhere from 3 months to 1 year to complete the entire engineering/FAA 
approval process. However, the FAA is concerned that the higher 
estimates may reflect the worst case. Based on airline reports, the FAA 
has determined that 4 months would be the average amount of time needed 
for the entire process. The FAA also has estimated that three industry 
engineers would work full time on each STC approval. The FAA has used 
an engineer hourly compensation rate of $100, which includes salary and 
fringe benefits plus a markup for the hours spent by supervisors, 
management, legal, etc. Thus, the FAA has estimated that each STC 
application would cost about $200,000. The FAA has further estimated 
that about 32 of these STC applications would be made. Thus, the FAA 
has estimated that the one-time engineering cost for the FDR system STC 
applications would be about $6.4 million.
    Thus, the FAA has estimated that the total one-time engineering 
costs for obtaining FAA-approved equipment and STCs would be about 
$9.15 million and would take about 5 months.

Equipment and Labor Costs to Retrofit FDR Systems

    The cost of an individual FDR system retrofit will depend on 
existing equipment and the number of flight data parameters currently 
recorded on any one airplane. In general, the FDR system components 
that would be affected by the proposed rule would be the FDR, FDAU, 
sensors, and wiring.
    As noted earlier, the FAA has relied upon industry estimates for 
the FDR system equipment costs and for the amount of labor time to 
complete these retrofits. However, the FAA has not used the actual 
industry labor rates. Instead, the FAA has developed an airplane 
mechanic hourly compensation rate of $75, which includes salary and 
fringe benefits plus an adjustment for the otherwise unaccounted hours 
spent by engineers, supervisors, management, etc., during an FDR system 
retrofit.
    With respect to the FDRs, the FAA has estimated that 156 B-737s 
would have their FDRs replaced whereas the remaining 1,150 B-737s would 
have their FDRs upgraded with additional memory. The FAA has determined 
that a new FDR would cost about $25,000; upgrading the memory of an 
older FDR that records 18 flight data parameters would cost about 
$10,000; upgrading the memory of an older FDR that records 22 flight 
data parameters would cost about $5,000; and upgrading the memory of a 
newer FDR that records more than 22 parameters would cost about $1,900. 
Although all FDR systems have an FDR, it would take more labor time to 
install a new recorder than to upgrade an FDR's memory because the 
former action would involve more FDR system testing and verifications 
than would the latter.
    Consequently, the FAA has estimated that upgrading to a new 
recorder would require 32 labor hours to remove the old recorder and to 
install and to test the new recorder. However, upgrading an FDR would 
require 16 labor hours because less testing of the FDR system would be 
needed. Thus, the FAA has estimated that the present value of the 
equipment cost for replaced or upgraded FDRs would be about $17.2 
million.
    With respect to the FDAUs, the FAA has estimated that a FDAU would 
need to be retrofitted into 496 B-737s, whereas the existing FDAUs in 
810 B-737s would need to be reprogrammed. In this case, ``FDAU 
reprogramming'' would involve both hardware modifications and software 
revisions.
    Retrofitting a B-737 with a FDAU would necessitate a complete 
rerouting of the FDR system wiring because the recorder itself (where 
the wires formerly terminated) is located in the back of the airplane, 
while the FDAU would be located in the front of the airplane. Thus, the 
wiring would now run from the sensors to the FDAU and then back to the 
recorder. The FAA has determined that a new FDAU would cost about 
$50,000 while reprogramming an existing FDAU would cost about $10,000. 
Relying primarily on estimates provided by airlines that have 
retrofitted FDAUs into their B-737s, the FAA has estimated that this 
retrofitting would take about 200 labor hours, which includes the 
associated labor hours to rewire the existing FDR system. The FAA also 
has estimated that the labor hours to remove, ship to the manufacturer, 
reinstall, and test a reprogrammed FDAU would take 48 hours for an 
older FDAU and about 40 hours for a newer FDAU. On that basis, the FAA 
has estimated that the present value of the FDAU equipment and 
associated labor costs would be about $37.6 million.
    With respect to the additional sensors and wiring, the FAA has 
divided the equipment and labor costs into two components: (1) The 
equipment and labor costs to add flight data parameters (a)(19) through 
(a)(22); and (2) the equipment and labor costs to add the proposed new 
flight data parameters (a)(89) through (a)(91) and to add flight data 
parameters found in (a)(88) with the proposed increased sampling rates.
    The FAA estimates of the costs of sensors and wiring to add 
parameters (a)(19) through (a)(22) is based on industry sources that 
have reported that the sensors to supply the additional flight data 
parameters to be recorded by the FDR generally cost between $200 and 
$2,000 each. These additional sensors would also require the addition 
of wiring to transmit their inputs to the FDAU. The FAA has estimated 
that the total cost of the sensors and wiring for a B-737 FDR system to 
add parameters (a)(19) through (a)(22) would be about $20,000.
    The FAA has primarily used the estimated labor hours supplied by 
airlines that have retrofitted flight data parameters (a)(19) through 
(a)(22) in their B-737s to estimate these costs. On that basis, the FAA 
has estimated that, in addition to the 200 labor hours associated with 
the FDAU rewiring, rewiring the sensors and wiring for flight data 
parameters (a)(19) through (a)(22) would take 200 labor hours for a B-
737-200, an Advanced B-737-200, or a B-737-400 and 400 labor hours for 
a B-737-300 or a B-737-500. Thus, the labor costs of adding flight data 
parameters (a)(19) through (a)(22) would be about $15,000 for a B-737-
200, an Advanced B-737-200, or a B-737-400, while it would be about 
$30,000 for a B-737-300 or a B-737-500.
    Thus, the FAA has estimated that the equipment and labor costs of 
adding flight data parameters (a)(19) through (a)(22) would be about 
$35,000 for a B-737-200, an Advanced B-737-200, or a B-737-400 while it 
would cost about $50,000 for a B-737-300 or a B-737-500.
    The primary difficulty in estimating the potential labor hours to 
retrofit proposed flight data parameters (a)(89) through (a)(91) is 
that these flight data parameters have not previously been recorded in 
any B-737. As a result, no engineering analysis has been completed that 
can serve as an experienced basis for an estimate. Consequently, the 
FAA has adopted some preliminary industry estimates that it would cost 
about $22,000 for the additional sensors and wiring to retrofit flight 
data parameters (a)(88) at a higher sampling rate and flight data 
parameters

[[Page 63150]]

(a)(89) through (a)(91) in a B-737 FDR system that now records at least 
22 flight data parameters. In addition, the FAA has estimated that this 
retrofit would involve about 360 labor hours. On that basis, the FAA 
has estimated that these labor costs would be about $27,000 per 
airplane.
    Thus, the FAA has estimated that the per-airplane equipment and 
labor costs of adding flight data parameter (a)(88) at a higher 
sampling rate and parameters (a)(89) through (a)(91) to a B-737 
currently recording 22 flight data parameters would be about $49,000.
    Finally, the FAA has adopted some preliminary industry estimates 
that it would cost about $12,000 for the additional sensors and wiring 
to retrofit flight data parameter (a)(88) at a higher sampling rate and 
flight data parameters (a)(89) through (a)(91) in a B-737 FDR system 
that now records 88 flight data parameters. In addition, the FAA has 
estimated that this retrofit would involve about 160 labor hours. On 
that basis, the FAA has estimated that these labor costs would be about 
$12,000 per airplane.
    Thus, the FAA has estimated that the per-airplane equipment and 
labor costs of adding flight data parameter (a)(88) at a higher 
sampling rate and parameters (a)(89) through (a)(91) to a B-737 
currently recording 88 flight data parameters would be about $24,000.
    Therefore, the FAA has estimated that retrofitting each B-737's 
sensors and wiring would cost about $84,000 and take about 560 labor 
hours for a B-737-200 or a B-737-400 without a FDAU; about $100,000 and 
take about 760 labor hours for a B-737-300 and B-737-500 without a 
FDAU; about $49,000 and take about 360 labor hours for an older B-737 
airplane with a FDAU; and about $24,000 and take about 160 labor hours 
for a newer B-737 airplane.
    As a result, the FAA has estimated that the present value over the 
next 18 months of the total sensor and wiring costs to retrofit all B-
737 FDR systems would be about $69 million.

Net Revenue Loss From Out-of-Service Time

    The proposed rule would, effectively, require a B-737 to be taken 
out of service due to the high number of labor hours for an FDR system 
retrofit and the fact that only a few mechanics can work on the 
airplane's FDR system simultaneously because of the limited physical 
work space. An out-of-service airplane does not generate net revenue 
and the longer the airplane is out of service, the greater the 
airline's net revenue loss. However, if a retrofit were completed while 
the B-737 is undergoing a regularly scheduled maintenance check, only 
the net revenue lost from any additional out-of-service time could be 
considered a cost of the proposed rule. For example, if an FDR system 
retrofit would take 6 days and the B-737 is scheduled for a 3-day 
maintenance check, only the lost net revenue from the additional 3 out-
of-service days would be a cost of the proposed rule. Thus, the lost 
net revenue due to an FDR system retrofit of a given duration depends 
upon whether the retrofit is performed during a regularly scheduled 
maintenance check or whether the airplane must be taken out of service 
solely to perform the retrofit.
    The FAA has estimated that retrofitting a B-737 with a FDAU and 
adding flight data parameters (a)(19) through (a)(22) would require 3 
days out-of-service time for a B-737-200, an Advanced B-737-200, or a 
B-737-400 while it would require 5 days out-of-service time for a B-
737-300 or a B-737-500. Based on a preliminary industry estimate, the 
FAA has also estimated that, for B-737s that currently record at least 
22 flight data parameters, adding proposed parameters (a)(89) through 
(a)(91) and flight data parameter (a)(88) with the proposed increased 
sampling rates, would require 4 days out-of-service time. The FAA has 
further estimated that a B-737 adding flight data parameters ((a)(19) 
through (a)(22) and (a)(88) through (a)(91)) would require 7 days out-
of-service time if retrofitting a B-737-200, a B-737-200 Advanced, or a 
B-737-400. It would require 9 days out-of-service time if retrofitting 
a B-737-300 or a B-737-500. If the retrofit were to be completed during 
a 3-day maintenance check, the FAA has estimated that the incremental 
out-of-service times due to the retrofit would be 2 days for a B-737 
that has a FDAU, 4 days for a B-737-200 that does not have a FDAU, and 
6 days for a B-737-300 or -500 that does not have a FDAU. If the 
retrofit were to be completed during a 14-day or a 21-day major 
maintenance check, the FAA has determined that the retrofit would 
create no incremental out-of-service time.
    The FAA has assumed that one 3-day maintenance check will occur 
every 18 months for each B-737 and that a major 14-day or 21-day 
maintenance check will occur every 5 years. As detailed in the Initial 
Regulatory Evaluation, the FAA has developed a probability distribution 
of the number of these B-737s by series and airplane age that would 
have had a scheduled 3-day or 14-day maintenance check between the 
estimated final rule effective date and the various compliance dates. 
On that basis, the FAA estimated the various numbers of out-of-service 
days for these airplanes.
    In calculating the lost net revenue due to out-of-service time, the 
FAA has taken the approach that an airplane is a piece of capital 
equipment for which the average net revenue would equal the average 
price of the airplane multiplied by the average annual risk-free 
productive rate of return of capital. Using OMB's mandated 7 percent 
average annual risk-free productive rate of return on capital, the FAA 
has calculated that the average out-of-service lost net revenue per day 
ranges from about $400 to about $10,500 per B-737, depending upon the 
series and its average age. Thus, the FAA has estimated that the 
present value of the total out-of-service lost net revenue due to 
retrofitting the B-737 FDR systems would be about $25.2 million.

Total One-Time FDR System Retrofitting Costs

    In summary, the FAA has estimated that the present value of the 
total one-time compliance costs to retrofit all B-737 FDR systems by 
the proposed compliance dates would be about $155 million.

Annual Costs Resulting From Retrofitting B-737 FDR Systems

    The proposed rule also would generate annual compliance costs from 
(1) The additional airplane weight from the retrofitted FDR system 
equipment and wiring; and (2) additional maintenance costs annually to 
validate the FDAU.
    The FAA has estimated that the proposed rule would add about 40 
pounds to a B-737 without a FDAU currently recording 18 flight data 
parameters and about 10 pounds to a B-737 currently recording at least 
22 flight data parameters. In calculating the estimated additional fuel 
cost, the FAA has assumed a per-airplane average of 2,800 flight hours 
per year, a price of $0.61 per gallon of aviation fuel, and 0.23 
additional gallons consumed per additional pound per flight hour, 
resulting in per-airplane annual costs of about $400 for a B-737 that 
would add 40 pounds and about $100 for a B-737 that would add 10 
pounds. On that basis, the FAA has estimated that the present value of 
the increased fuel consumption over the next 20 years would be about 
$3.6 million.
    The FAA has further estimated that annual validation of a FDAU 
would cost about $750. This incremental compliance cost would be 
incurred only for B-737s retrofitted with FDAUs

[[Page 63151]]

because the operators of the other B-737s have elected to install this 
equipment and, therefore, the validation cost would not be attributed 
to this proposed rule. Based on the number of B-737s that would have 
had FDAUs retrofitted and their expected retirement rates over the 20-
year time period, the FAA has calculated that the present value of this 
annual FDAU validation over the next 20 years would be about $2.7 
million.
    Thus, the FAA has estimated that the present value of the annual 
compliance costs over the next 20 years would be about $6.3 million.

Compliance Costs for Future Manufactured B-737

    Installing additional proposed flight data parameters (a)(89) 
through (a)(91) would also impose compliance costs upon all future 
manufactured B-737s because, absent the proposed rule, those airplanes 
would not have been manufactured to record those parameters. However, 
newly manufactured B-737s are capable of recording all of the 
additional flight data parameters with the exception of the standby 
rudder on/off discrete (parameter (a)(91)) and the increase in 
recording rates of all force information from once per second to twice 
per second (parameter (a)(88)). As a result, the proposed rule would 
impose production costs for additional wiring, sensors, and testing as 
well as a cost to install an upgraded FDR system. There would be no 
additional costs to upgrade the FDAU because the units currently 
installed in production are capable of processing these additional 
flight data parameters. The FAA has estimated that the additional 
wiring and testing for production would cost about $25,000, a midstream 
rudder force transducer would cost about $12,000, and the FDR upgrade 
would cost about $1,900, for a total of $38,900 per future manufactured 
B-737 beginning in the year 2001. On that basis, the FAA has calculated 
that the present value of the additional costs for the approximately 
2,144 U.S.-registered B-737s to be manufactured during the next 20 
years would be about $40.4 million.

Potential Net Revenue Losses Currently Unquantifiable

    The FAA's analysis of the net revenue losses for an out-of-service 
airplane, although appropriate for the individual airplanes within an 
airline's system, may not capture all of the potential lost revenue 
when the entire system must comply within a short period of time. In 
recognition of this potential analytical shortcoming, the FAA had 
queried airlines concerning the potential system impacts. However, the 
FAA has also realized that much of the information needed to perform a 
more complete airline system analysis is proprietary and airlines are 
extremely reluctant to provide it for fear of the data being 
inappropriately or inadvertently disseminated to competitors. 
Nevertheless, following discussions with the aviation industry, the FAA 
believes that there are two areas of potential economic impact that may 
need additional investigation, but for which the FAA does not have 
adequate information.
    The first area is that the FAA analysis has assumed that the time 
to obtain the FAA approvals and the STC would not significantly affect 
the airlines' abilities to meet the compliance dates. However, there is 
a possibility that several of the airlines or repair stations would not 
be able to obtain the requisite FAA approvals to be able to complete 
these retrofits (particularly those for the proposed new flight data 
parameters (a)(89) through (a)(91)) in the time between the 
promulgation of the final rule and the August 18, 2000, or even the 
August 20, 2001, compliance date. If, in fact, airline maintenance and 
repair facilities would be overwhelmed with idle B-737s that cannot 
return to service until they have been retrofitted, then the FAA may 
have significantly underestimated the actual out-of-service times.
    The second area is that the FAA does not have an appropriate model 
to determine the impact on the number of available flights when, for 18 
months, large numbers of airplanes would be taken out of service for 
several days. For example, there is the possibility that air travel 
service in certain markets would be disrupted, fares would increase, 
load factors would increase and flights would become more crowded, some 
passengers would choose not to fly, some passengers would be unable to 
obtain flights at the times and dates they are accustomed to flying, 
flight delays due to weather or mechanical problems would be longer 
because there would be fewer airplanes available to fill in, etc.
    In order to attempt to develop some estimates of the economic 
impacts of these economic effects that have not been quantified, the 
FAA specifically requests comments and supporting data on the magnitude 
of these potential effects, including any presumptions applicable to an 
individual operator or the industry as a whole.

Benefit-Cost Comparison of the Proposed Rule

    In comparing the estimated benefits and costs, the FAA has 
determined that if the proposed rule would prevent one accident during 
the first 6 years after it would be promulgated, the benefits would be 
greater than the costs. However, there is uncertainty about this 
estimate because it depends on whether the future is adequately modeled 
by past events and the amount of the currently unquantifiable net 
revenue losses. As a result, the FAA has determined that it is in 
general agreement with the NTSB recommendations that this information 
is needed.

Alternatives to the Proposed Rule

    The FAA has determined that its responsibilities under the 
Regulatory Flexibility Act and the Unfunded Mandates Act require an 
analysis of alternatives to the proposed rule for each purpose. Rather 
than repeating the alternatives in each of those two sections, they are 
listed in this separate section for reference.
    The FAA has evaluated three alternatives to the proposed rule. In 
formulating the alternatives, the FAA focused on its responsibility for 
aviation safety and its particular obligation under 49 U.S.C. 44717 to 
ensure the continuing airworthiness of airplanes. As a result, the 
three evaluated alternatives to the proposed rule differ only with 
respect to the dates of compliance--not on the content of the proposed 
rule.

Alternative 1

    Require all B-737s that currently have FDAUs (not just those B-737s 
that had a FDAU installed prior to July 16, 1996) to record all of the 
proposed flight data parameters by August 18, 2000, rather than by 
August 20, 2001. This would shorten the compliance date for an 
estimated 197 B-737s by one year. Alternative 1 would increase 
compliance costs not because the actual retrofitting costs would change 
but because the lost net revenue from out-of-service time would be 
greater for some airplanes. A shorter compliance time increases the 
likelihood that the retrofit would be done as a special project and not 
as part of a regularly scheduled maintenance check. On that basis, the 
FAA has estimated that Alternative 1 would increase first-year 
compliance costs by $2.4 million above those costs associated with the 
proposed rule. However, this alternative could be considerably more 
expensive than the proposed rule, particularly if the idle airplane and 
scheduling costs that the

[[Page 63152]]

FAA could not quantify are substantial. In that case, the shorter the 
compliance period, the greater the idle airplane costs and scheduling 
costs. As a result, in comparison to Alternative 1, the proposed rule 
would offer considerably more relief to the airlines than is evidenced 
by the quantified difference between them.
    Alternative 1 would not significantly increase the estimated 
quantitative benefits because the probability of one of these 197 
airplanes having an accident whose probable cause would not have been 
determined within a one-year timeframe is remote. As a result, the FAA 
has determined that a commensurate increased level of benefits would 
not match the increased cost of this Alternative 1.

Alternative 2

    Delay the compliance date for all B-737s to August 20, 2001. This 
would extend the compliance date by one year for about 292 airplanes. 
The FAA has determined that Alternative 2 could reduce compliance costs 
by about $7.3 million. This alternative would provide all B-737 
operators with greater scheduling flexibility in determining when to 
have the airplane retrofitted. A greater number of these operators 
would be able to delay compliance until a regularly scheduled 
maintenance check and, thereby, reduce the lost revenue from out-of-
service time. However, the FAA must also note that the converse to the 
effect described under Alternative 1 would be a factor. Again, the 
greater the unquantified costs, the greater the reduction in costs 
associated with delaying compliance dates. As Alternative 2 would allow 
greater flexibility than the proposed rule, the estimated compliance 
cost reduction from Alternative 2 could be substantially 
underestimated.
    However, Alternative 2 could reduce the expected quantitative 
benefits. There is a probability that one of these 292 airplanes could 
have an accident or an incident whose cause would have been discovered 
only if the additional flight data parameters had been recorded. In 
light of the fact that the NTSB has recommended the August 18, 2000, 
compliance date, the FAA has decided to meet the majority of the NTSB 
recommendations and not propose a later compliance date for all B-737s.

Alternative 3

    Delay the proposed compliance date for every B-737 until either its 
next scheduled major (4 days or more) maintenance check or by August 
18, 2004. Alternative 3 would give an operator its maximum retrofitting 
scheduling flexibility. As the FAA has determined that nearly every B-
737 will have at least one scheduled major maintenance check within any 
5-year time period, Alternative 3 would allow the operator to perform 
the retrofit during a scheduled major maintenance check, which would 
eliminate the additional out-of-service time and, hence, the potential 
lost net revenue from compliance with the proposed rule. In addition, 
Alternative 3 would spread the cost of the retrofits over a 5-year time 
period. By doing so, the present value of the compliance cost from 
Alternative 3 would be about $172.8 million, which would be about $32.6 
million less than the compliance cost of the proposed rule. Further, 
the FAA reiterates that the greater the unquantified costs, the greater 
the reduction in costs associated with delaying compliance dates. As 
Alternative 3 would allow greater flexibility than the proposed rule, 
the estimated compliance cost reduction associated with Alternative 3 
could be substantially underestimated.
    Alternative 3 would reduce the expected quantitative benefits 
because it would reduce the number of flight hours that the B-737 fleet 
would have recorded the additional flight data parameters by about 6.6 
million flight hours during those 4.5 years. Further, it would reduce 
the cumulative probability that the additional recorded flight data 
parameters from an accident or incident involving a B-737 could provide 
information that would result in preventive regulatory or industry 
action. Consequently, since the FAA agrees with the NTSB recommendation 
that this information is important, the FAA has not proposed the 
delayed compliance date presented in Alternative 3.
    Thus, in comparison to the one higher cost alternative and the two 
lower cost alternatives evaluated by the FAA, the FAA has determined 
that the proposed rule would be the best method to address this safety 
issue.

Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 establishes ``as a principle 
of regulatory issuance that agencies shall endeavor, consistent with 
the objective of the rule and of applicable statutes, to fit regulatory 
and informational requirements to the scale of the business, 
organizations, and governmental jurisdictions subject to regulation.'' 
To achieve that principle, the Act requires agencies to solicit and 
consider flexible regulatory proposals and to explain the rationale for 
their actions. The Act covers a wide range of small entities, including 
small businesses, not-for-profit organizations, and small governmental 
jurisdictions.
    Agencies must perform a review to determine whether a proposed or 
final rule will have a significant economic impact on a substantial 
number of small entities. If the agency determines that it will, the 
agency must prepare a Regulatory Flexibility Analysis (RFA) as 
described in the Act.
    However, if an agency determines that a proposed or final rule is 
not expected to have a significant economic impact on a substantial 
number of small entities, section 605(b) of the Act provides that the 
head of the agency may so certify, and an RFA is not required. The 
certification must include a statement providing the factual basis for 
this determination, and the reasoning should be clear.
    Recently, the Office of Advocacy of the Small Business 
Administration (SBA) published new guidance for Federal agencies in 
responding to the requirements of the Regulatory Flexibility Act. 
Application of that guidance to the proposed rule indicates that it 
could have a significant economic impact on a substantial number of 
small airlines. Accordingly, a complete initial regulatory flexibility 
analysis was conducted for the proposed rule and is summarized as 
follows:

Reasons Why the FAA is Considering the Proposed Rule

    The flight data being recorded have not been sufficiently 
comprehensive to determine the causes of several B-737 accidents and 
incidents. As a result, the FAA and the aviation industry have been 
unable to develop specific actions that may prevent similar future B-
737 accidents and incidents.

The Objectives and Legal Basis for the Proposed Rule

    The objective of the proposed rule is to require the B-737 fleet to 
record additional flight data parameters that may help determine the 
cause(s) of a B-737 accident, and, thereby allow the development of 
regulatory and industry actions that could prevent similar future 
accidents. The legal basis for the proposed rule is 49 U.S.C. 44901 et 
seq. As a matter of policy, the FAA must, as its highest priority (49 
U.S.C. 40101 (d)), maintain and enhance safety and security in air 
commerce.

[[Page 63153]]

All Relevant Federal Rules That May Duplicate, Overlap, or Conflict 
With the Proposed Rule

    The FAA is unaware of any federal rules that would duplicate, 
overlap, or conflict with the proposed rule.

A Description and an Estimate of the Number of Small Entities to 
Which the Proposal Would Apply

    The proposed rule would apply to the operators of all U.S.-
registered B-737 airplanes operated under part 91, part 121, part 125, 
or under part 129.
    Nearly all of the 16 operators flying B-737s under part 91 (under 
deviation authority from part 125) use the airplane as an ancillary 
part of their primary business (for example, oil, automobile 
manufacturing, etc.). As a result, these operators are distributed 
across a spectrum of Standard Industrial Classification (SIC) codes, 
and, as listed in the Initial Regulatory Evaluation, few are small 
businesses.
    The FAA has determined that the 3 non-U.S. operators of U.S.-
registered B-737s operating under part 129 are not small entities.
    However, as seen shown in Table 2, based on a SBA definition that a 
small airline has fewer than 1,500 employees, the FAA has determined 
that 14 small airlines (assuming Accessair is a small airline and 
noting that Metrojet is owned by USAirways) operating under part 121 
would be affected by the proposed rule. The number of affected B-737s 
reported in Table 3 is an FAA estimate of the number of those airplanes 
by airline on August 2000.

                                 Table 3.--Affected Airlines by Number of B-737s
----------------------------------------------------------------------------------------------------------------
                                                                                     Operating
                    Operator                       Number of B-      Number of    revenues (in $  Net profit (in
                                                        737          employees       millions)      $ millions)
----------------------------------------------------------------------------------------------------------------
Southwest.......................................             322          19,933       3,438.762         413.602
USAirways.......................................             205          43,100       8,556.000         965.182
United..........................................             190          76,000      17,472.106         774.128
Continental.....................................             185          40,700       7,155.384         389.816
Delta...........................................              90          58,097      14,584.906       1,073.535
America West....................................              70          10,013       1,962.480         104.350
Alaska..........................................              50          10,137       1,553.158         106.162
Aloha...........................................              20           2,365         231.141           6.278
Frontier........................................              19             440         174.713         (3.308)
Metrojet........................................              15  ..............  ..............  ..............
Winair..........................................              12              52           4.939         (1.150)
Vanguard........................................              10             480          97.755         (7.460)
Airtran.........................................               9             600  ..............         (6.985)
Eastwind........................................               6             800          22.641         (8.684)
Pro Air.........................................               6             110          11.247        (18.849)
Accessair.......................................               3  ..............  ..............  ..............
Pace............................................               3              20           4.914           0.256
Casino Express..................................               2             102          15.692         (2.676)
Ryan Int........................................               2             575         138.769  ..............
American........................................               1         111,300      16,394.548       1,097.339
Lorair..........................................               1              23  ..............  ..............
Nations Air.....................................               1             154           6.724           0.299
North American..................................               1             127          61.473           1.434
Sierra Pacific..................................               1              35           6.650           0.631
                                                 ---------------------------------------------------------------
      Total.....................................  ..............  ..............  ..............  ..............
----------------------------------------------------------------------------------------------------------------

The Projected Reporting, Recordkeeping, and Other Compliance 
Requirements of the Proposed Rule

    Existing 14 CFR part 43, in part, already prescribes the content, 
form, and disposition of maintenance, preventive maintenance, 
rebuilding, and alteration records for any aircraft having a U.S. 
airworthiness certificate or any foreign-registered aircraft used in 
common carriage under part 121. There would be one-time paperwork costs 
of about $9.15 million to obtain FAA parts approvals and STCs for the 
modified FDR systems, but nearly all of these costs would be incurred 
by large airlines and large repair stations and large parts 
manufacturers. Finally, the proposed rule would necessitate minimal 
additional annual maintenance, which would require minutes of annual 
recordkeeping per airplane and negligible recordkeeping costs.

Regulatory Flexibility Cost Analysis

    The compliance costs associated with the proposed rule are almost 
completely specific to an individual airplane. There would be minimal 
economies of scale in completing the FDR system retrofits. Thus, the 
compliance cost for an individual B-737 is largely independent of the 
size of the airline. The estimated present value of the compliance 
costs per B-737 by series and FDR system capability is summarized in 
Table 1. However, if the 1997 flight data recorder revisions and this 
proposed rule are viewed as two parts of one rulemaking extended over 
time, then the estimated per airplane cost would be increased by about 
$45,000.

Affordability Analysis

    As seen in Table 2, the FAA has obtained 1997 net profit data for 
11 of the 14 affected small airlines, although the FAA lacks detailed 
financial data for most of them. Of those 11 small airlines, 7 reported 
losses. Of the remaining 4 small airlines, the compliance costs would 
have turned one airline's positive profit into a loss, cut another's 
profit in half, and reduced the others' profits by 16 percent and by 7 
percent. When coupled with the costs to comply with the 1997 flight 
data recorder revisions, these profits would have been further reduced 
and the losses would have been further increased. Consequently, the FAA 
has concluded that some of these small airlines may face financial 
difficulties in offsetting these compliance costs. The FAA solicits 
comments on the affordability of the

[[Page 63154]]

proposed rule for small airlines and requests that all comments be 
accompanied with clear supporting data.

Disproportionality Analysis

    As noted earlier in this regulatory flexibility cost analysis, the 
incremental compliance costs for a B-737 operated by a large airline 
and those costs for an identical B-737 operated by a small airline 
would be nearly identical. However, to the extent that financing 
charges tend to be larger for a small airline than for a large airline 
with a better-established credit line, the financing costs for the 
retrofit would be disproportionally larger for a small airline than for 
a large airline. The FAA does not have information concerning this 
potential impact. Nevertheless, the significant disproportionality that 
may occur would depend upon the percentage of an airline's fleet that 
is composed of B-737s. The higher the percentage of B-737s, the greater 
the impact of this proposed rule on that airline. In reviewing the 
composition of these various fleets, the FAA has determined that there 
is not a significant difference, on average, between the group of large 
airlines and the group of small airlines--although there are certainly 
differences among individual airlines. As a result, small airlines 
operating B-737s would not be disadvantaged, as a group, relative to 
the group of large airlines operating B-737s.

Competitiveness Analysis

    The proposed rule would impose significant first-year costs on all 
operators of B-737s and, as a consequence, may affect the relative 
position of these airlines in their markets. As the proposed rule would 
impose no costs on other small operators using McDonnell Douglas or 
Airbus airplanes, the FAA has determined that there could be a 
significantly adverse competitiveness effect on certain small (and 
large) airlines that operate B-737s. The principle beneficiaries would 
be other small and large airlines that do not operate B-737s.

Business Closure Analysis

    The FAA is unable to determine with certainty whether any of these 
small airlines would close their operations. Many very small operations 
(1 to 4 airplanes) operate very close to the margin, as evidenced by 
their constant exit from and entry into various markets. As noted, most 
of the small airlines reported losses, but, in the absence of 
sufficiently detailed financial data, the FAA cannot determine which, 
if any, of these small airlines would close due to the proposed rule.

Description of Alternatives

    The three alternatives evaluated by the FAA are discussed in an 
earlier preamble section. As described, delaying the compliance dates 
would provide some relief to the affected small and large airlines. 
However, the proposed rule would still provide a competitive advantage 
to airlines operating airplanes other than B-737s over small and large 
airlines that operate B-737s.

Special Considerations

    Although the proposed rule would have a significant economic impact 
on small airlines, the FAA has not exempted them from the proposed 
rule. The principal reason for not exempting them is that B-737 
accidents and incidents whose causes have not been determined are not 
related to the size of the operator; both large and small airlines have 
been affected. For example, incidents have occurred to B-737s operated 
by small airlines. In particular, the 1996 Eastwind B-737 incident is 
very similar to the United and USAir B-737 accidents. The Eastwind 
airplane recorded only 11 flight data parameters and, consequently, 
that incident's cause has not been fully determined. Thus, the FAA has 
determined that special considerations for small airlines would not be 
appropriate.

Conclusion

    The FAA has determined that there are no viable alternatives to the 
proposed rule for small airlines. Consequently, the FAA has concluded 
that exempting B-737s or delaying compliance dates for B-737s operated 
by small airlines would be an inappropriate action and inconsistent 
with the FAA mandate to ensure aviation safety. The FAA requests 
comments on this initial regulatory flexibility analysis and requests 
commenters to supply supporting data for the comments.

International Trade Impact Assessment

    Consistent with the Administration's belief in the general 
superiority, desirability, and efficacy of free trade, it is the policy 
of the Administrator to remove or diminish, to the extent feasible, 
barriers to international trade, including both barriers affecting the 
export of American goods and services to foreign countries and those 
affecting the import of foreign goods and services into the United 
States.
    In accordance with that policy, the FAA is committed to develop as 
much as possible its aviation standards and practices in harmony with 
its trading partners. Significant cost savings can result from this 
harmonization, both to American companies doing business in foreign 
markets, and foreign companies doing business in the United States.
    This proposed rule would have a minimal impact on international 
trade. Although it would increase the cost of manufacturing a future B-
737 by about $39,000, the FAA does not believe that this increase would 
have a significantly negative effect on Boeing's future domestic or 
international markets for the B-737.

Unfunded Mandates Assessment

    Title II of the Unfunded Mandates Reform Act of 1995 (the Act), 
enacted as Public Law 104-4 on March 22, 1995, requires each Federal 
agency, to the extent permitted by law, to prepare a written assessment 
of the effects of any Federal mandate in a proposed or final agency 
rule that may result in the expenditure by State, local, and tribal 
governments, in the aggregate, or by the private sector, of $100 
million or more (adjusted annually for inflation) in any one year. 
Section 204(a) of the Act, 2 U.S.C. 1534(a), requires the Federal 
agency to develop an effective process to permit timely input by 
elected officers (or their designees) of State, local, and tribal 
governments on a proposed ``significant intergovernmental mandate.'' A 
``significant intergovernmental mandate'' under the Act is any 
provision in a Federal agency regulation that will impose an 
enforceable duty upon state, local, and tribal governments, in the 
aggregate, of $100 million (adjusted annually for inflation) in any one 
year. Section 203 of the Act, 2 U.S.C. 1533, which supplements section 
204(a), provides that before establishing any regulatory requirements 
that might significantly or uniquely affect small governments, the 
agency shall have developed a plan that, among other things, provides 
for notice to potentially affected small governments, if any, and for a 
meaningful and timely opportunity to provide input in the development 
of regulatory proposals.
    Under 49 U.S.C. 40101(d)(1), the FAA Administrator is required to 
consider the following matter, among others, as being in the public 
interest: maintaining and enhancing safety and security as the highest 
priorities in air commerce. Additionally it is the Administrator's 
statutory duty to perform the responsibilities ``in a way that best 
tends to reduce or eliminate the

[[Page 63155]]

possibility or recurrence of accidents in air transportation.'' (See 49 
U.S.C. 44701(c).)
    The FAA has determined that this proposed rule would not contain a 
significant intergovernmental mandate as defined by the Act because the 
FAA has no knowledge of any State, local, or tribal government 
operating a B-737.
    However, the FAA has determined that this proposed rule would 
contain a significant private sector mandate as defined by the Act 
because the compliance costs over the first 18 months would be about 
$243 million for the private sector. Thus, the FAA has evaluated the 
three previously described alternatives in order to determine if the 
burden could be reduced in a manner consistent with the FAA's mandate 
to provide aviation safety. Of the three alternatives, only Alternative 
3 (delaying compliance until a scheduled major maintenance check) would 
lower the compliance costs below $100 million for every year. 
Nevertheless, for the reasons discussed in that earlier section, the 
FAA has determined that Alternative 3 would not attain the same level 
of B-737 risk reduction at a lower cost than the proposed rule.

Federalism Implications

    The regulations proposed herein would not have a substantial direct 
effect on the States, on the relationship between the national 
Government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a federalism assessment.

Environmental Analysis

    FAA Order 1050.1D defines FAA actions that may be categorically 
excluded from preparation of a National Environmental Policy Act (NEPA) 
environmental assessment or environmental impact statement. In 
accordance with FAA Order 1050.1D, appendix 4, paragraph 4(j), this 
rulemaking action qualifies for a categorical exclusion.

Energy Impact

    The energy impact of the proposed rule has been assessed in 
accordance with the Energy Policy and Conservation Act (EPCA) and 
Public Law 94-163, as amended (42 U.S.C. 6362). It has been determined 
that it is not a major regulatory action under the provisions of EPCA.

Comment Period

    Comments on this proposed rule must be received by the agency 
within 30 days of the date of publication of this document. The FAA 
understands that this does not allow affected operators and other 
interested parties much time to gather and submit the information 
requested by the FAA. However, the agency has determined that it is 
more important to give affected operators the maximum available time to 
comply with the new requirements once a final rule is adopted. The FAA 
generally agrees with the NTSB that B-737 airplanes be retrofitted to 
record the additional flight data by August 18, 2000. The FAA has 
determined that the short time available requires that the comment 
period on this rule be kept to a minimum. The FAA also notes that there 
has been considerable publicity concerning the NTSB recommendations, 
and that questions addressed to the FAA indicate that the recommended 
actions and the issues surrounding them are well known.
    For these reasons, the FAA strongly encourages commenters to submit 
their comments as soon as possible. Late-filed comments will be 
considered to the extent that they do not unnecessarily delay the 
promulgation of a final rule.

List of Subjects

14 CFR Part 91

    Aviation safety, Reporting and recordkeeping requirements.

14 CFR Part 121

    Air carriers, Aviation safety, Air transportation, Reporting and 
recordkeeping requirements.

14 CFR Part 125

    Aviation safety, Reporting and recordkeeping requirements.

The Proposed Amendment

    In consideration of the foregoing, the Federal Aviation 
Administration proposes to amend parts 91, 121, and 125 of Title 14, 
Code of Federal Regulations as follows:

PART 91--GENERAL OPERATING AND FLIGHT RULES

    1. The authority citation for part 91 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 1155, 40103, 40113, 40120, 44101, 
44701, 44705, 44709, 44711, 44712, 44715, 44716, 44717, 44722, 
44901, 46306, 46315, 46316, 46504, 46506-46507, 47122, 47508, 47528-
47531, articles 12 and 29 of the Convention on International Civil 
Aviation (61 stat. 1180).

    2. Section 91.609 is amended by adding a new paragraph (h) to read 
as follows:


Sec. 91.609  Flight recorders and cockpit voice recorders.

* * * * *
    (h) An aircraft operated under this part under deviation authority 
from part 125 of this chapter must comply with all of the applicable 
flight data recorder requirements of part 125 applicable to the 
aircraft, notwithstanding such deviation authority.

PART 121--OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL 
OPERATIONS

    3. The authority citation for part 121 continues to read as 
follows:

    Authority: 49 U.S.C. 106(g), 40113, 40119, 44101, 44701-44702, 
44705, 44709-44711, 44713, 44716-44717, 44722, 44901, 44903-44904, 
44912, 46105.

    4. Section 121.344 is amended in paragraph (a) by removing the word 
``and'' after paragraph (a)(87); by removing the period after paragraph 
(a)(88) and adding a semicolon in its place; and by adding new 
paragraphs (a) (89), (90), and (91), (d)(3), (e)(3) and (m); and by 
revising paragraphs (b) introductory text, (c) introductory text, and 
(f) to read as follows:


Sec. 121.344  Digital flight data recorders for transport category 
airplanes.

    (a) * * *
    (89) Yaw damper status;
    (90) Yaw damper command; and
    (91) Standby rudder status.
    (b) Except for Boeing 737 model airplanes, for all turbine-engine 
powered transport category airplanes manufactured on or before October 
11, 1991, by August 20, 2001--
* * * * *
    (c) Except for all Boeing 737 model airplanes, for all turbine-
engine powered transport category airplanes manufactured on or before 
October 11, 1991--
* * * * *
    (d) * * *
    (3) In addition to the requirements of paragraphs (d)(1) and (d)(2) 
of this section, all Boeing 737 model airplanes also must comply with 
the requirements of paragraph (m)(1) or (m)(2) of this section, as 
applicable.
* * * * *
    (e) * * *
    (3) In addition to the requirements of paragraphs (e)(1) and (e)(2) 
of this section, all Boeing 737 model airplanes, also must comply with 
the requirements of paragraph (m)(1) of this section.

[[Page 63156]]

    (f) For all turbine-engine powered transport category airplanes 
manufactured after August 19, 2002--
    (1) The parameters listed in paragraphs (a)(1) through (a)(88) of 
this section must be recorded within the ranges, accuracies, 
resolutions and recording intervals specified in appendix M to this 
part.
    (2) In addition to the requirements of paragraph (f)(1) of this 
section, all Boeing 737 model airplanes, also must also comply with the 
requirements of paragraph (m)(1) of this section.
* * * * *
    (m) In addition to all other applicable requirements of this 
section, all Boeing 737 model airplanes must record the parameters 
listed in paragraphs (a)(1) through (a)(22) and (a)(88) through (a)(91) 
of this section, within the ranges, accuracies, resolutions, and 
recording intervals specified in appendix M to this part, in accordance 
with the following schedule:
    (1) All Boeing 737 model airplanes equipped with a flight data 
acquisition unit of any type as of July 16, 1996, or manufactured after 
July 16, 1996, must comply by August 18, 2000.
    (2) All Boeing 737 model airplanes not equipped with a flight data 
acquisition unit of any type as of July 16, 1996, must comply by August 
20, 2001.
    5. Appendix M to part 121 is amended by revising item 88 and adding 
items 89 through 91 to read as follows:

Appendix M to Part 121--Airplane Flight Recorder Specification--
Continued

* * * * * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Accuracy  (sensor     Seconds per sampling
             Parameter                        Range                  input)                 interval              Resolution              Remarks
--------------------------------------------------------------------------------------------------------------------------------------------------------
88. All cockpit flight control       Full range............  5%........  1....................  0.2% of full range...  For fly-by-wire
 input forces (control wheel,          Control wheel 70 lbs.                                                                               systems, where
                                       Control column 85 lbs.                                                                               surface position is
                                       Rudder pedal 70 lbs.                                                                               displacement of the
                                                                                                                                    control input device
                                                                                                                                    only, it is not
                                                                                                                                    necessary to record
                                                                                                                                    this parameter. For
                                                                                                                                    airplanes that have
                                                                                                                                    a flight control
                                                                                                                                    break away
                                                                                                                                    capability that
                                                                                                                                    allows either pilot
                                                                                                                                    to operate the
                                                                                                                                    control
                                                                                                                                    independently,
                                                                                                                                    record both control
                                                                                                                                    force inputs. The
                                                                                                                                    control force inputs
                                                                                                                                    may be sampled
                                                                                                                                    alternately once per
                                                                                                                                    2 seconds to produce
                                                                                                                                    the sampling
                                                                                                                                    interval of 1.
89. Yaw damper status..............  Discrete (on/off).....  ......................  0.5..................  .....................  .....................
90. Yaw damper command.............  Full range............  As installed..........  0.5..................  1% of full range.....  .....................
91. Standby rudder status..........  Discrete (on/off).....  ......................  0.5..................  .....................  .....................
--------------------------------------------------------------------------------------------------------------------------------------------------------
\14\ For all Boeing 737 model airplanes, the seconds per sampling interval is 0.5 per control input; remarks do not apply.

PART 125--CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING 
CAPACITY OF 20 OR MORE PASSENGER OR A MAXIMUM PAYLOAD CAPACITY OF 
6,000 POUNDS OR MORE

    6. The authority citation for part 125 continues to read as 
follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44705, 44710-
44711, 44713, 44716-44717, 44722.

    7. Section 125.3 is amended by adding a new paragraph (d) to read 
as follows:


Sec. 125.3  Deviation authority.

* * * * *
    (d) No deviation authority from the flight data recorder 
requirements of this part will be granted. Any previously issued 
deviation from the flight data recorder requirements of this part is no 
longer valid.
    8. Section 125.226 is amended in paragraph (a) by removing the word 
``and'' after paragraph (a)(87); by removing the period after paragraph 
(a)(88) and adding a semicolon in its place; by adding new paragraphs 
(a)(89), (90), and (91), (d)(3), (e)(3), and (m); and by revising 
paragraphs (b) introductory text, (c) introductory text, and (f) to 
read as follows:


Sec. 125.226  Digital flight data recorders.

    (a) * * *
    (89) Yaw damper status;
    (90) Yaw damper command; and
    (91) Standby rudder status.
    (b) Except for Boeing 737 model airplanes, for all turbine-engine 
powered transport category airplanes manufactured on or before October 
11, 1991, by August 20, 2001--
    (c) Except for all Boeing 737 model airplanes, for all turbine-
engine powered transport category airplanes

[[Page 63157]]

manufactured on or before October 11, 1991--
    (d) * * *
    (3) In addition to the requirements of paragraphs (d)(1) and (d)(2) 
of this section, all Boeing 737 model airplanes also must comply with 
the requirements of paragraph (m)(1) or (m)(2) of this section, as 
applicable.
    (e) * * *
    (3) In addition to the requirements of paragraphs (e)(1) and (e)(2) 
of this section, all Boeing 737 model airplanes, also must comply with 
the requirements of paragraph (m)(1) of this section.
    (f) For all turbine-engine powered transport category airplanes 
manufactured after August 19, 2002--
    (1) The parameters listed in paragraphs (a)(1) through (a)(88) of 
this section must be recorded within the ranges, accuracies, 
resolutions and recording intervals specified in appendix E to this 
part.
    (2) In addition to the requirements of paragraph (f)(1) of this 
section, all Boeing 737 model airplanes must also comply with the 
requirements of paragraph (m)(1) of this section.
* * * * *
    (m) In addition to all other applicable requirements of this 
section, all Boeing 737 model airplanes must record the parameters 
listed in paragraphs (a)(1) through (a)(22) and (a)(88) through (a)(91) 
of this section, within the ranges, accuracies, resolutions, and 
recording intervals specified in appendix E to this part, in accordance 
with the following schedule:
    (1) All Boeing 737 model airplanes equipped with a flight data 
acquisition unit of any type as of July 16, 1996, or manufactured after 
July 16, 1996, must comply by August 18, 2000.
    (2) All Boeing 737 model airplanes not equipped with a flight data 
acquisition unit of any type as of July 16, 1996, must comply by August 
20, 2001.
    9. Appendix E to part 125 is amended by revising item 88, and 
adding items 89 through 91 to read as follows:

Appendix E to Part 125--Airplane Flight Recorder Specification--
Continued

* * * * * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Accuracy (sensor      Seconds per sampling
             Parameter                        Range                  input)                 interval              Resolution              Remarks
--------------------------------------------------------------------------------------------------------------------------------------------------------
88. All cockpit flight control       Full range............  5%........  1....................  0.2% of full range...  For fly-by-wire
 input forces (control wheel,          Control wheel 14.      minus>70 lbs.                                                                               systems, where
                                       Control column 85 lbs.                                                                               surface position is
                                       Rudder pedal 165 lbs.                                                                              displacement of the
                                                                                                                                    control input device
                                                                                                                                    only, it is not
                                                                                                                                    necessary to record
                                                                                                                                    this parameter. For
                                                                                                                                    airplanes that have
                                                                                                                                    a flight control
                                                                                                                                    break away
                                                                                                                                    capability that
                                                                                                                                    allows either pilot
                                                                                                                                    to operate the
                                                                                                                                    control
                                                                                                                                    independently,
                                                                                                                                    record both control
                                                                                                                                    force inputs. The
                                                                                                                                    control force inputs
                                                                                                                                    may be sampled
                                                                                                                                    alternately once per
                                                                                                                                    2 seconds to produce
                                                                                                                                    the sampling
                                                                                                                                    interval of 1.
89. Yaw damper status..............  Discrete (on/off).....  ......................  0.5..................  .....................  .....................
90. Yaw damper command.............  Full range............  As installed..........  0.5..................  1% of full range.....  .....................
91. Standby rudder status..........  Discrete (on/off).....  ......................  0.5..................  .....................  .....................
--------------------------------------------------------------------------------------------------------------------------------------------------------
\14\ For all Boeing 737 model airplanes, the seconds per sampling interval is 0.5 per control input; remarks do not apply.

    Issued in Washington, DC, on November 9, 1999.
Ronald T. Wojnar,
Acting Director, Aircraft Certification Service.
[FR Doc. 99-29758 Filed 11-17-99; 8:45 am]
BILLING CODE 4910-13-P