[Federal Register Volume 71, Number 97 (Friday, May 19, 2006)]
[Proposed Rules]
[Pages 29092-29096]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-7633]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-21968; Directorate Identifier 2005-NM-077-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 757-200, -200CB, and -300 
Series Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: The FAA is revising an earlier proposed airworthiness 
directive (AD) for certain Boeing Model 757-200, -200CB, and -300 
series airplanes. The original NPRM would have required repetitive 
detailed inspections for proper functioning of the girt bar leaf 
springs for the escape slides to ensure the leaf springs retain the 
sliders and the required 0.37-inch minimum engagement between the 
sliders and floor fittings is achieved at passenger doors 1, 2, and 4, 
and corrective actions if necessary. The original NPRM resulted from a 
report that the escape slides failed to deploy correctly during an 
operator's tests of the escape slides. This action revises the original 
NPRM by stating that this proposed AD would not include procedures from 
the airplane maintenance manuals and component maintenance manuals that 
allow bending the girt bar retention springs. We are proposing this 
supplemental NPRM to prevent escape slides from disengaging from the 
airplane during deployment or in use, which could result in injuries to 
passengers or flightcrew.

DATES: We must receive comments on this supplemental NPRM by June 13, 
2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this supplemental NPRM.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this 
proposed AD.

FOR FURTHER INFORMATION CONTACT: Patrick Gillespie, Aerospace Engineer, 
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 917-6429; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this supplemental NPRM. Send your comments to an 
address listed in the ADDRESSES section. Include the docket number 
``Docket No. FAA-2005-21968; Directorate Identifier 2005-NM-077-AD'' at 
the beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of this 
supplemental NPRM. We will consider all comments received by the 
closing date and may amend this supplemental NPRM in light of those 
comments.
    We will post all comments submitted, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this supplemental NPRM. Using the search function 
of that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level in the Nassif Building at the DOT 
street address stated in ADDRESSES. Comments will be available in the 
AD docket shortly after the Docket Management System receives them.

Discussion

    We proposed to amend 14 CFR part 39 with a notice of proposed 
rulemaking (NPRM) for an AD (the ``original NPRM'') for certain Boeing 
Model 757-200, -200CB, and -300 series airplanes. The original NPRM was 
published in the Federal Register on July 27, 2005 (70 FR 43343). The 
original NPRM

[[Page 29093]]

proposed to require repetitive detailed inspections for proper 
functioning of the girt bar leaf springs for the escape slides at 
passenger doors 1, 2, and 4, and corrective actions if necessary.

Comments

    We have considered the following comments on the original NPRM.

Support for the Original NPRM

    The Air Transport Association (ATA), on behalf of seven of its 
member airlines (America West, American, Continental, Delta, Northwest, 
and United), and Brittania Airways agree with the intent of the 
original NPRM.

Request To Address Bending of Retention Spring

    The Air Transport Association (ATA) on behalf of its members 
Continental and United, noted an inconsistency with the airplane 
maintenance manuals (AMMs) and component maintenance manuals (CMMs) 
referenced in Boeing Special Attention Service Bulletins 757-52-0085 
and 757-52-0086, both dated March 24, 2005. These service bulletins 
were referenced as the appropriate source of service information for 
accomplishing the proposed actions. Continental and United state that 
the AMMs and CMMs allow bending of the retention spring, which is not 
the intent of the proposed AD, and suggest that we state the intent of 
the AD clearly. They also suggest that the proposed AD note this 
difference with the AMMs.
    We agree with the requests to clarify the proposal by stating that 
bending of the retention spring is not allowed. Since this change 
expands the scope of the original NPRM, we have determined that it is 
necessary to reopen the comment period.

Request To Revise Summary

    Boeing requests that we revise the ``Summary'' paragraph to clarify 
the inspection requirements. Boeing suggests inserting the following 
words: ``* * * to ensure the leaf springs retain the sliders and the 
required 0.37-inch minimum engagement between the sliders and the floor 
fittings is achieved * * *.''
    We agree. The words Boeing suggests add detail that clarifies the 
summary. We have revised the ``Summary'' paragraph of this supplemental 
NPRM to include the suggested words.

Request To Correct Errors in ``Differences'' Paragraph and in Paragraph 
(g)

    Boeing also requests that we revise the ``Differences Between the 
Proposed AD and the Service Bulletin'' paragraph to correct errors in 
the text. Boeing specifically requests that we add ``/section'' to the 
following sentence and revise the reference to the actions in Part 1 to 
the actions in Part 2. Boeing suggests the following wording: 
``However, for actions in Part 2--`Inspection' of the Accomplishment 
Instructions of the applicable service bulletin, this proposed AD would 
require operators to accomplish the actions in accordance with the 
applicable chapter/section of the AMM or CMM specified in the 
applicable service bulletin.'' Boeing notes that these changes revise 
the Part reference to agree with the reference in the special attention 
service bulletins; and clarify the reference to the AMM and CMM.
    Boeing also states that paragraph (g) of the original NPRM 
incorrectly references Part 1 of the service bulletin rather than Part 
2. Boeing requests that we clarify paragraph (g) by adding the words 
``applicable'' and ``/section'' when referring to the 757 AMM or CMM. 
Boeing states that making these changes would revise the supplemental 
NPRM to agree with the Part number in the service bulletin, and also 
clarify the subject of the AMM or CMM.
    We agree that the reference to Part 1 in paragraph (g) of the 
original NPRM is incorrect. We also agree that adding the requested 
words would clarify paragraph (g) of the reasons stated. We have 
revised paragraph (g) of the supplemental NPRM to refer to Part 2 of 
the service bulletin, and to add the requested words. The changes also 
correct and clarify the ``Differences'' paragraph. We have revised the 
subject paragraph as requested.

Request for Permanent Design Modification

    Northwest Airlines notes that it has had difficulty in complying 
with the engagement dimension required by paragraph (f) of the original 
NPRM. The difficulty continued after Northwest coordinated process 
improvements with Boeing, and after it installed new girt bar parts and 
assemblies. Northwest proposes that the unsafe condition be addressed 
by a permanent design modification to the girt bars, or by a redesign 
of the retention springs. Northwest states that without a design 
change, operators can expect a high rate of girt bar replacements.
    We partially agree. We agree that the best solution to this unsafe 
condition is a design change that would also serve as a terminating 
action for the repetitive inspections. However, in lieu of a permanent 
design modification proposed by either Boeing or an airplane operator, 
we have determined that repetitive inspections for adequate retention 
force of the leaf spring, and for slider engagement dimension are 
necessary. We will continue to work with Boeing and the airplane 
operators to identify a permanent solution. We have also added an 
``Interim Action'' paragraph to this supplemental NPRM to note that we 
do not consider the proposed actions to be a permanent solution.

Request To Include Terminating Action for Repetitive Inspections

    The ATA, on behalf of its members Delta and United, requests that 
we evaluate Boeing Service Bulletin 757-52-0087 as a terminating action 
for the proposed inspections. Delta also suggests that the service 
bulletin should be evaluated as an action that would extend the 
repetitive inspection intervals. Delta notes that this service bulletin 
is currently pending and has not been released. This pending service 
bulletin would provide procedures for replacing the current leaf spring 
with a stronger leaf spring.
    We have evaluated the procedures in pending Boeing Service Bulletin 
757-52-0087. However, both we and Boeing concluded that replacing the 
current leaf spring with a stronger leaf spring in accordance with the 
pending service bulletin does not represent a final design solution for 
the unsafe condition in this supplemental NPRM. The actions in this 
pending service bulletin, based on current data, also do not provide 
justification for extending the repetitive interval. As noted in 
``Request for Permanent Design Modification'' above, we do not consider 
the actions proposed in this supplemental NPRM to be a permanent 
solution. We have not changed the supplemental NPRM in this regard. 
However, if a new service bulletin is issued and approved, and it 
addresses the unsafe condition, operators may request an alternative 
method of compliance (AMOC) in accordance with the procedures in 
paragraph (h) of this proposed AD.

Request To Revise Repetitive Inspection Interval

    The ATA, on behalf of America West and Continental, and Brittania 
Airways request that we revise the repetitive inspection interval. 
America West states that it would be difficult to comply with the 
repetitive interval of ``on or after each maintenance task.'' America 
West notes that the required maintenance records and the inability to 
positively account for every maintenance task would result in the 
inability to demonstrate compliance with the original NPRM. Brittania 
believes that it

[[Page 29094]]

is punitive to require certification of AD compliance every time ``on 
or after each maintenance task where removal of and installation of the 
girt bar is necessary.'' Brittania states that such matters are best 
addressed by the maintenance manual to which responsible operators 
adhere. Continental does not object to doing the initial inspection 
within 24 months after the effective date of the forthcoming AD. 
However, Continental notes that it currently removes the door slides 
and performs an operational check of the girt bar every 36 months. 
Continental states that these two maintenance planning document (MPD) 
driven actions are independent of one another and typically do not 
coincide. Consequently, the actual interval can vary from 1 month to 36 
months. Continental states that introducing the third program specified 
in the original NPRM, at 24-month intervals, would inevitably become a 
stand-alone door maintenance event. Continental notes that realizing 
the full 24-month repetitive inspection interval is unlikely due to the 
two MPD programs. Further, Continental believes that these girt bar 
inspection requirements are ideally suited as a base maintenance 
activity and not as a line maintenance activity.
    We disagree with the request to revise the repetitive inspection 
interval. We acknowledge that a repetitive inspection is not the 
optimum solution to the unsafe condition addressed by this supplemental 
NPRM. In lieu of an alternative proposal, we agree with Boeing's 
recommendation to rely on detailed inspections until a permanent 
solution is developed. In developing an appropriate repetitive interval 
for this supplemental NPRM, we considered safety issues as well as the 
recommendations of the manufacturer, and the practical aspect of 
accomplishing the required inspection within an interval of time that 
corresponds to the normal maintenance schedules of most affected 
operators. However, maintenance programs vary from operator to operator 
and may be assessed individually as an alternative method of compliance 
(AMOC) for the actions in this supplemental NPRM. In addition, the 
specific operator maintenance programs may qualify as an acceptable 
AMOC, but the repetitive inspection as defined in this supplemental 
NPRM is not required by the Boeing 757 MPD. We encourage all operators 
to coordinate their maintenance programs with the FAA to ensure 
compliance with the applicable requirements and to identify suitable 
AMOCs. Operators may request an AMOC in accordance with the procedures 
in paragraph (h) of this supplemental NPRM. We have not changed the 
supplemental NPRM in this regard.

Suggestions for Different Inspection Methods

    The ATA on behalf of American Airlines, and Brittania suggested 
more effective and efficient methods for conducting the proposed 
inspections. American Airlines states that its inspection method 
produces more reliable data from which to make continued serviceability 
determinations. Brittania maintains that its currently scheduled 
maintenance tasks nullify the requirement to adopt the proposed 
inspections.
    We welcome suggestions that improve airplane safety and that also 
support operational requirements. To this end, paragraph (h) of this 
supplemental NPRM authorizes the Manager, Seattle Aircraft 
Certification office, FAA to approve AMOCs. Operators may request AMOCs 
for inspection methods in accordance with the procedures in that 
paragraph. We have not changed the supplemental NPRM in this regard.

Request To Revise Paragraph (e)

    Boeing requests that we revise paragraph (e) of the original NPRM 
to delete the phrase, ``unless the actions have already been done.'' 
Boeing states that operators still have to comply with the detailed 
inspection and corrective actions within 24 months after the effective 
date of the proposed AD and repeat the inspections at the specified 
interval.
    We disagree. The intent of paragraph (e) is to give credit to 
operators who have performed compliant actions before the effective 
date of the AD. The paragraph does not apply to ongoing actions that 
are required after the AD becomes effective. We have not changed the 
supplemental NPRM in this regard.

Request To Clarify Paragraph (f)

    The ATA, on behalf of Delta, requests that we clarify the language 
in paragraph (f) of the original NPRM. Delta specifically would like 
clarification of our intent when we say ``removal and installation.'' 
Delta believes that the intent of this statement is for the removal and 
installation of the girt bar assembly in the slide lanyard. Delta notes 
that, as written, the proposed rule would require the necessary 
inspections for the girt bar removal and installation in the floor 
fittings as well as the removal and installation in the lanyard.
    We disagree. The statement as written refers to only maintenance 
tasks that involve installation of the girt bar on the slide assembly. 
The statement does not pertain to girt bar slider engagement with the 
floor fittings. We have not changed the supplemental NPRM in this 
regard.

Suggestions To Revise CMM and AMM

    United recommends including in the service bulletin the 
instructions from CMM 25-66-14. Continental requests that the AMMs be 
revised to remove the procedure that allows for bending of the springs.
    We agree that it is best that all documents related to the AD 
action be consistent. However, we cannot revise manufacturers' service 
information. It is our understanding that Boeing is revising the CMM. 
If the revised information affects the AD action, we may consider 
further rulemaking then.

Request To Justify AD Action

    Brittania notes that the original NPRM was raised in response to a 
single operator's experience.
    We infer that Brittania believes the proposed AD is not justified. 
We disagree that the action is not justified and that it results from a 
single operator's experience. The ``Summary'' paragraph states that the 
original NPRM resulted from a report that the escape slides failed to 
deploy correctly during an operator's tests of the escape slides. That 
report prompted an FAA evaluation of the current Boeing 757 girt bar 
design, and of related service difficulties reported fleet-wide. We 
have not changed the supplemental NPRM in this regard.

Request To Revise Cost Estimate

    The ATA, on behalf of American Airlines, Delta, and Northwest; and 
Boeing suggest changes to the number of work-hours stated to accomplish 
the inspection. American notes that the current estimate is appropriate 
only for personnel experienced with this proposed inspection. The other 
operators and Boeing note that the estimated cost in the service 
bulletin is 6.3 work-hours per airplane.
    We disagree. We recognize that the operators and Boeing have 
experience with the required inspection and maintenance task and agree 
with the overall work-hour estimate. However, the cost figures 
discussed in AD rulemaking actions represent only the time necessary to 
perform the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions. The 2

[[Page 29095]]

work-hour estimate is based on the task breakdown provided in Boeing 
Special Attention Service Bulletins 757-52-0085 and 757-52-0086, and is 
consistent with the work breakdowns submitted by the commenters. We 
have not changed the supplemental NPRM in this regard.

Clarification of Alternative Method of Compliance (AMOC) Paragraph

    We have revised this action to clarify the appropriate procedure 
for notifying the principal inspector before using any approved AMOC on 
any airplane to which the AMOC applies.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

    Certain changes discussed above expand the scope of the original 
NPRM; therefore, we have determined that it is necessary to reopen the 
comment period to provide additional opportunity for public comment on 
this supplemental NPRM.

Differences Between the Supplemental NPRM and the Service Bulletins

    Although the AMMs referenced in the service bulletins allow for 
bending of the girt bar retention springs, this supplemental NPRM would 
not allow any procedure that allows bending of the girt bar retention 
springs.
    The service bulletins specify that operators may accomplish certain 
actions in accordance with the Boeing 757 AMM, the Boeing 757 CMM, or 
an ``approved equivalent procedure.'' However, for actions in Part 2--
``Inspection'' of the Accomplishment Instructions of the applicable 
service bulletin, this proposed AD would require operators to 
accomplish the actions in accordance with the applicable chapter/
section of the AMM or CMM specified in the applicable service bulletin. 
An ``approved equivalent procedure'' may be used only if it is approved 
as an alternative method of compliance in accordance with paragraph (h) 
of this supplemental NPRM.

Interim Action

    We consider this proposed AD interim action. If final action is 
later identified, we may consider further rulemaking then.

Explanation of Change to Costs of Compliance

    After the original NPRM was issued, we reviewed the figures we have 
used over the past several years to calculate AD costs to operators. To 
account for various inflationary costs in the airline industry, we find 
it necessary to increase the labor rate used in these calculations from 
$65 per work hour to $80 per work hour. The cost impact information, 
below, reflects this increase in the specified hourly labor rate.

Costs of Compliance

    There are about 944 airplanes of the affected design in the 
worldwide fleet. This supplemental NPRM would affect about 632 
airplanes of U.S. registry. The proposed inspection would take about 2 
work hours per airplane, at an average labor rate of $80 per work hour. 
Based on these figures, the estimated cost of the supplemental NPRM for 
U.S. operators is $101,120, or $160 per airplane, per inspection cycle.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the 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. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this supplemental NPRM and placed it in the AD docket. See 
the ADDRESSES section for a location to examine the regulatory 
evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

    Boeing: Docket No. FAA-2005-21968; Directorate Identifier 2005-
NM-077-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by June 13, 
2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 757-200 and -200CB series 
airplanes, certificated in any category, as identified in Boeing 
Special Attention Service Bulletin 757-52-0085, dated March 24, 
2005; and Boeing Model 757-300 series airplanes, certificated in any 
category, as identified in Boeing Special Attention Service Bulletin 
757-52-0086, dated March 24, 2005.

Unsafe Condition

    (d) This AD results from a report that the escape slides failed 
to deploy correctly during an operator's tests of the escape slides. 
We are issuing this AD to prevent escape slides from disengaging 
from the airplane during deployment or in use, which could result in 
injuries to passengers or flightcrew.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Detailed Inspection and Corrective Actions

    (f) Within 24 months after the effective date of this AD: Do a 
detailed inspection for inadequate spring retention force and 
inadequate girt bar slider dimensions of the girt bar leaf springs 
for the escape slides at passenger doors 1, 2, and 4; and do any 
applicable corrective actions before further

[[Page 29096]]

flight. Do all the actions in accordance with the Accomplishment 
Instructions of the applicable service bulletin in paragraph (f)(1) 
or (f)(2) of this AD, except as provided by paragraph (g) of this 
AD. Where the airplane maintenance manuals (AMMs) and component 
maintenance manuals (CMMs) referenced by the applicable service 
bulletin include procedures that allow bending the girt bar 
retention spring, this AD does not allow that procedure. Repeat the 
inspection thereafter at intervals not to exceed 24 months, or after 
each maintenance task where removal of and installation of the girt 
bar is necessary, whichever occurs earlier.
    (1) For Boeing Model 757-200 and -200CB series airplanes: Boeing 
Special Attention Service Bulletin 757-52-0085, dated March 24, 
2005.
    (2) For Boeing Model 757-300 series airplanes: Boeing Special 
Attention Service Bulletin 757-52-0086, dated March 24, 2005.

Equivalent Procedures

    (g) Where Part 2--``Inspection'' of the applicable service 
bulletin in paragraph (f)(1) or (f)(2) of this AD specifies that 
actions may be accomplished in accordance with an ``approved 
equivalent procedure'': The corrective actions must be accomplished 
in accordance with the applicable chapter/section of the Boeing 757 
AMM or Boeing 757 CMM specified in the applicable service bulletin. 
Where the AMMs and CMMs include procedures that allow bending the 
girt bar retention spring, this AD does not allow that procedure.

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

    Issued in Renton, Washington, on May 11, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-7633 Filed 5-18-06; 8:45 am]
BILLING CODE 4910-13-P