[Federal Register Volume 64, Number 44 (Monday, March 8, 1999)]
[Proposed Rules]
[Pages 10959-10962]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-5549]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-326-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-9-80 Series 
Airplanes and Model MD-88 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to all McDonnell Douglas Model 
DC-9-80 series airplanes and Model MD-88 airplanes. That AD currently 
requires a revision to the Airplane Flight Manual (AFM) to specify 
restrictions on operations during icing conditions, and installation of 
tufts and triangular decals on the inboard side of the wing upper 
surfaces, and a revision to the AFM to specify restrictions on 
operations when such tufts or decals are missing. This action would 
require installation of an overwing heater blanket system or a primary 
wing ice detection system, and a new revision to the AFM to advise the 
flightcrew of the hazards associated with ice accumulation on wing 
surfaces. This proposal is prompted by incidents in which ice 
accumulation on the wing upper surfaces shed into the engines during 
takeoff. The actions specified by the proposed AD are intended to 
prevent such ice accumulation, which could result in ingestion of ice 
into one or both engines and consequent loss of thrust from one or both 
engines.

DATES: Comments must be received by April 22, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-326-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from The Boeing Company, Douglas Products Division, 3855 
Lakewood Boulevard, Long Beach, California 90846, Attention: Technical 
Publications Business Administration, Dept. C1-L51 (2-60). This 
information may be examined at the FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport 
Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 
Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT: Albert Lam, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130L, FAA, Transport Airplane 
Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount 
Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5346; 
fax (562) 627-5210.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 98-NM-326-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 98-NM-326-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On January 3, 1992, the FAA issued AD 92-03-02, amendment 39-8156 
(57 FR 2014, January 17, 1992), applicable to all McDonnell Douglas 
Model DC-9-80 series airplanes and Model MD-88 airplanes, to require a 
revision to the

[[Page 10960]]

FAA-approved Airplane Flight Manual (AFM) to specify that takeoff may 
not be initiated unless the flightcrew verifies that visual and 
physical checks of the wing upper surfaces have been accomplished, and 
that the wing is clear of ice accumulation. That AD also requires 
installation of tufts and triangular decals on the inboard side of wing 
upper surfaces. That action was prompted by several incidents in which 
ice build-up on wing upper surfaces may have shed into the engines 
during takeoff, causing damage to one or both engines. The requirements 
of that AD are intended to prevent such ice build-up, which, if not 
corrected, could result in loss of thrust from one or both engines.

Actions Since Issuance of Previous Rule

    Since the issuance of that AD, several incidents occurred in which 
ice that had accumulated on the wing upper surfaces shed during takeoff 
and was ingested into an engine, which resulted in damage to the 
engine. In those incidents, the wings of the airplanes reportedly had 
been subjected to visual and physical checks to detect ice accumulation 
on the wing upper surfaces, in accordance with the AFM revision 
required by AD 92-03-02. Reportedly, no ice was detected during those 
inspections.
    In the preamble to AD 92-03-02, the FAA indicated that the actions 
required by that AD were considered ``interim action'' and that further 
rulemaking action was being considered. The FAA finds that the physical 
and visual checks to detect ice accumulation, as specified by the AFM 
revision required by AD 92-03-02, may not be adequate to ensure the 
safety of the affected transport airplane fleet. Therefore, the FAA has 
determined that further rulemaking action is indeed necessary, and this 
proposed AD follows from that determination.

Explanation of Relevant Service Information

    The FAA has reviewed and approved McDonnell Douglas Service 
Bulletins MD80-30-071, Revision 02, dated February 6, 1996; and MD80-
30-078, Revision 01, dated April 8, 1997. Those service bulletins 
describe procedures for installation of an overwing heater blanket 
system. The procedures include installation of an overwing heater 
blanket assembly on each wing; a heater control unit in the mid cargo 
compartment; and associated system wiring, circuit breakers, and 
cockpit switches. For certain airplanes (Group 3), service bulletin 
MD80-30-071, Revision 02, also describes procedures for removal of the 
overwing ice detector system from the wing upper surfaces. 
Accomplishment of the actions specified in the applicable service 
bulletin is intended to adequately address the identified unsafe 
condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would supersede AD 92-03-02 to continue to require a 
revision to the AFM to specify that takeoff may not be initiated unless 
the flightcrew verifies that visual and physical checks of the wing 
upper surfaces have been accomplished, and that the wing is clear of 
ice accumulation. The proposed AD also would continue to require 
installation of tufts and triangular decals on the inboard side of the 
wing upper surfaces, and a revision to the Configuration Deviation List 
(CDL) appendix of the AFM to specify restrictions on operations when 
such tufts and decals are not present. In addition, the proposed AD 
would require installation of an overwing heater blanket system or a 
primary wing ice detection system, and a new revision to the AFM to 
advise the flightcrew of the hazards associated with ice accumulation 
on wing surfaces. After accomplishment of the installation and 
insertion of the new revision into the AFM, the AFM revision that 
specifies visual and physical inspections to detect ice accumulation on 
the wing may be removed from the AFM, and the tufts and triangular 
decals may be removed from the airplane.
    Installation of an overwing heater blanket system, if accomplished, 
would be required to be accomplished in accordance with the applicable 
service bulletin described previously, except as discussed below; or in 
accordance with certain Supplemental Type Certificates identified in 
the proposed rule. Installation of a primary wing ice detection system, 
if accomplished, would be required to be accomplished in accordance 
with a method approved by the FAA.

Differences Between Proposed Rule and Service Bulletins

    McDonnell Douglas Service Bulletins MD80-30-071, Revision 02, dated 
February 6, 1996, and MD80-30-078, Revision 01, dated April 8, 1997, 
describe procedures for installation of an overwing heater blanket 
system. Operators should note that this AD proposes to mandate, within 
3 years, the installation of an overwing heater blanket system or a 
primary wing ice detection system. Installation of an overwing heater 
blanket system is classified as optional in the service bulletins.
    The FAA has determined that long-term continued operational safety 
will be better assured by design changes to remove the source of the 
problem, rather than by repetitive inspections. Long-term inspections 
may not be providing the degree of safety assurance necessary for the 
transport airplane fleet. This, coupled with a better understanding of 
the human factors associated with numerous continual inspections, has 
led the FAA to consider placing less emphasis on inspections and more 
emphasis on design improvements. The proposed installation is in 
consonance with these conditions.

Cost Impact

    There are approximately 1,153 airplanes of the affected design in 
the worldwide fleet. The FAA estimates that 643 airplanes of U.S. 
registry would be affected by this proposed AD.
    The AFM revision that is currently required by AD 92-03-02 takes 
approximately 1 work hour per airplane to accomplish, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the currently required AFM revision on U.S. operators is 
estimated to be $38,580, or $60 per airplane.
    The revision of the CDL that is currently required by AD 92-03-02 
takes approximately 1 work hour per airplane to accomplish, at an 
average labor rate of $60 per work hour. Based on these figures, the 
cost impact of the CDL revision on U.S. operators is estimated to be 
$38,580, or $60 per airplane.
    The installation of tufts and decals that is currently required by 
AD 92-03-02 takes approximately 3 work hours per airplane to 
accomplish, at an average labor rate of $60 per work hour. Required 
parts cost approximately $25 per airplane. Based on these figures, the 
cost impact of the currently required installation of tufts and decals 
on U.S. operators is estimated to be $131,815, or $205 per airplane.
    The installation of the wing heater system that is proposed as one 
option for compliance with this AD action would take approximately 254 
work hours per airplane to accomplish, at an average labor rate of $60 
per work hour. Required parts would cost approximately $62,166 per 
airplane. Based on these figures, the cost impact of the installation 
proposed by this AD on U.S. operators is estimated to be $77,406 per 
airplane.

[[Page 10961]]

    In lieu of installation of a wing heater system, this proposed AD 
provides for installation of a primary wing ice detector system. 
Because the manufacturer has not issued service information that 
describes the procedures for such an installation, the FAA is unable at 
this time to provide specific information as to the number of work 
hours or cost of parts that would be required to accomplish that 
proposed installation. However, based on estimated costs provided by 
the manufacturer, the FAA can reasonably estimate that the proposed 
installation would require 200 work hours to accomplish, at an average 
labor rate of $60 per work hour. The cost of required parts is 
estimated to be $31,341 per airplane. Based on these figures, the cost 
impact of the installation of a primary wing ice detector system 
proposed by this AD on U.S. operators is estimated to be $43,341 per 
airplane.
    The new AFM revision that is proposed in this AD action would take 
approximately 1 work hour per airplane to accomplish, at an average 
labor rate of $60 per work hour. Based on these figures, the cost 
impact of the new AFM revision proposed by this AD on U.S. operators is 
estimated to be $38,580, or $60 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or proposed 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects 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.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, will not have a significant economic impact, 
positive or negative, on a substantial number of small entities under 
the criteria of the Regulatory Flexibility Act. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (14 CFR part 39) as 
follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-8156 (57 FR 
2014, January 17, 1992), and by adding a new airworthiness directive 
(AD), to read as follows:

McDonnell Douglas: Docket 98-NM-326-AD. Supersedes AD 92-03-02, 
Amendment 39-8156.

    Applicability: All Model DC-9-81, -82, -83, and -87 series 
airplanes; and Model MD-88 airplanes; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (f)(1) 
of this AD. The request should include an assessment of the effect 
of the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent ice accumulation on the wing upper surfaces, which 
could result in ingestion of ice into one or both engines and 
consequent loss of thrust from one or both engines, accomplish the 
following:

Restatement of Requirements of AD 92-03-02

    (a) Within 10 days after January 17, 1992 (the effective date of 
AD 92-03-02, amendment 39-8156), revise the Limitations Section of 
the FAA-approved Airplane Flight Manual (AFM) to include the 
following. This may be accomplished by inserting a copy of this AD 
in the AFM.

``Ice on Wing Upper Surfaces

Caution

    Ice shedding from the wing upper surface during takeoff can 
cause severe damage to one or both engines, leading to surge, 
vibration, and complete thrust loss. The formation of ice can occur 
on wing surfaces during exposure of the airplane to normal icing 
conditions. Clear ice can also occur on the wing upper surfaces when 
cold-soaked fuel is in the main wing fuel tanks, and the airplane is 
exposed to conditions of high humidity, rain, drizzle, or fog at 
ambient temperatures well above freezing. Often, the ice 
accumulation is clear and difficult to detect visually. The ice 
forms most frequently on the inboard, aft corner of the main wing 
tanks. [END OF CAUTIONARY NOTE]
    The wing upper surfaces must be physically checked for ice when 
the airplane has been exposed to conditions conducive to ice 
formation. Takeoff may not be initiated unless the flight crew 
verifies that a visual check and a physical (hands-on) check of the 
wing upper surfaces have been accomplished, and that the wing is 
clear of ice accumulation when any of the following conditions 
occur:
    (1) When the ambient temperature is less than 50 degrees F and 
high humidity or visible moisture (rain, drizzle, sleet, snow, fog, 
etc.) is present;
    (2) When frost or ice is present on the lower surface of either 
wing;
    (3) After completion of de-icing.
    When tufts and triangular decals are installed in accordance 
with McDonnell Douglas MD-80 Service Bulletin 30-59, the physical 
check may be made by assuring that all installed tufts move freely.

Note

    This limitation does not relieve the requirement that aircraft 
surfaces are free of frost, snow, and ice accumulation, as required 
by Federal Aviation Regulations Sections 91.527 and 121.629. [END OF 
NOTE]''
    (b) Within 10 days after January 17, 1992, revise the 
Configuration Deviation List (CDL) Appendix of the FAA-approved AFM 
to include the following. This may be accomplished by inserting a 
copy of this AD in the AFM.

``30-80-01 Triangular Decal and Tuft Assemblies

    Up to two (2) decals or tufts per side may be missing, provided:
    (a) At least one decal and tuft on each side is located along 
the aft spar line; and
    (b) The tufts are used for performing the physical check to 
determine that the upper wing is free of ice by observing that the 
tufts move freely.
    Up to eight (8) decals and/or tufts may be missing, provided:
    (a) Takeoff may not be initiated unless the flight crew verifies 
that a physical (hands-on) check is made of the upper wing in the 
location of the missing decals and/or tufts to assure that there is 
no ice on the wing when icing conditions exist; OR
    (b) When the ambient temperature is more than 50 degrees F.''

[[Page 10962]]

    (c) Within 30 days after January 17, 1992, install tufts and 
triangular decals on the inboard side of the wings' upper surfaces, 
in accordance with McDonnell Douglas Service Bulletin 30-59, dated 
September 18, 1989; Revision 1, dated January 5, 1990; or Revision 
2, dated August 15, 1990.

New Requirements of This AD

Corrective Actions

    (d) Within 3 years after the effective date of this AD, 
accomplish the requirements of either paragraph (d)(1) or (d)(2) of 
this AD.
    (1) Install an overwing heater blanket system in accordance with 
McDonnell Douglas Service Bulletin MD80-30-071, Revision 02, dated 
February 6, 1996, or McDonnell Douglas Service Bulletin MD80-30-078, 
Revision 01, dated April 8, 1997, as applicable; or in accordance 
with Supplemental Type Certificate (STC) SA6042NM or STC SA6061NM.
    (2) Install an FAA-approved primary wing ice detection system in 
accordance with a method approved by the Manager, Los Angeles 
Aircraft Certification Office (ACO), FAA, Transport Airplane 
Directorate.

    Note 2: McDonnell Douglas has received FAA approval of an 
acceptable primary wing ice detection system. This modification has 
been assigned a McDonnell Douglas service bulletin number but, at 
this time, no service bulletin is available.

AFM Revision

    (e) Prior to further flight after accomplishment of the 
installation required by paragraph (d)(1) or (d)(2) of this AD, 
revise the Limitations Section of the FAA-approved AFM to include 
the following. This may be accomplished by inserting a copy of this 
AD in the AFM. After accomplishment of the installation required by 
paragraph (d) of this AD and this AFM revision, the AFM revisions 
required by paragraphs (a) and (b) of this AD may be removed from 
the AFM, and the tufts and triangular decals required by paragraph 
(c) of this AD may be removed from the airplane.

``Ice on Wing Upper Surfaces

Caution

    Ice shedding from the wing upper surface during takeoff can 
cause severe damage to one or both engines, leading to surge, 
vibration, and complete thrust loss. The formation of ice can occur 
on wing surfaces during exposure of the airplane to normal icing 
conditions. Clear ice can also occur on the wing upper surfaces when 
cold-soaked fuel is in the main wing fuel tanks, and the airplane is 
exposed to conditions of high humidity, rain, drizzle, or fog at 
ambient temperatures well above freezing. Often, the ice 
accumulation is clear and difficult to detect visually. The ice 
forms most frequently on the inboard, aft corner of the main wing 
tanks. [END OF CAUTIONARY NOTE]

Alternative Methods of Compliance

    (f)(1) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Los Angeles ACO. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Los Angeles ACO.
    (2) Alternative methods of compliance, approved previously in 
accordance with AD 92-03-02, amendment 39-8156, are approved as 
alternative methods of compliance with this AD.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

Special Flight Permits

    (g) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.

    Issued in Renton, Washington, on March 1, 1999.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-5549 Filed 3-5-99; 8:45 am]
BILLING CODE 4910-13-U