[Federal Register Volume 67, Number 186 (Wednesday, September 25, 2002)]
[Proposed Rules]
[Pages 60196-60199]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-24306]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-343-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-100, -200, -200C, -
300, -400, and -500 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

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

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), applicable to certain Boeing Model 737-100, -200, -
200C, -300, -400, and -500 series airplanes, that would have required 
inspection of landing gear parts and/or their records to see that parts 
have serial numbers and that each part's number of flight cycles has 
been tracked; assignment of serial numbers and flight cycle use numbers 
if necessary; and removal of individual landing gear components from 
service when they reach their life limit. This new action revises the 
proposed rule by adding landing gear parts to the lists of safe-life 
components, and assigning life limits to landing gear parts already in 
service. The actions specified by this new proposed AD are intended to 
prevent failure of landing gear parts, which could lead to landing gear 
collapse. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by October 21, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-343-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-343-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington. This information may be examined at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Suzanne Lucier, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2186; fax (425) 227-1181.

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 action may be changed in 
light of the comments received.
    Submit comments using the following format:
    [sbull] Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
    [sbull] For each issue, state what specific change to the proposed 
AD is being requested.
    [sbull] Include justification (e.g., reasons or data) for each 
request.
    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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2000-NM-343-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. 2000-NM-343-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series 
airplanes, was published as a notice of proposed rulemaking (NPRM) in 
the Federal Register on August 28, 2001 (66 FR 45194). That NPRM would 
have required inspection of landing gear parts and/or their records to 
see that parts have serial numbers and that each part's number of 
flight cycles has been tracked; assignment of serial numbers and flight 
cycle use numbers if necessary; and removal of individual landing gear 
components from service when they reach their life limit. Failure of 
landing gear parts, if not corrected, could lead to landing gear 
collapse.

Actions Since Issuance of Previous Proposal

    Since the issuance of the original NPRM, the FAA has received 
reports from the manufacturer indicating that, during a check of the 
list of life-limited parts for the main landing gear and nose landing 
gear on Model 737 series airplanes, some life-limited parts were not 
included in the tables in Part 2 of the Accomplishment Instructions of

[[Page 60197]]

Boeing Service Bulletin 737-32-1322, dated September 30, 1999. To 
correct this exclusion, the manufacturer issued Boeing Service Bulletin 
737-32-1322, Revision 1, dated September 27, 2001, which has been 
reviewed and approved by the FAA. This new revision of the service 
bulletin includes the previously omitted life-limited parts. Failure to 
remove these ``safe-life'' parts at their life limit could result in 
failure of landing gear parts, which could lead to landing gear 
collapse.

Compliance Time Changes

    In paragraphs (a), (b), and (c) of the NPRM, the FAA specified the 
compliance time as, ``During the next gear overhaul or within 10 years 
from the effective date of this AD, whichever occurs later.'' Since 
there is no specific required time for ``the next gear overhaul,'' we 
have removed that provision from this supplemental NPRM.

Comments

    Due consideration has been given to the comments received in 
response to the original NPRM.

Request to Cite Revision 1 of the Service Bulletin

    The manufacturer, Boeing, states that Boeing Service Bulletin 737-
32-1322, Revision 1, dated September 27, 2001, was issued to add part 
numbers for any life-limited spares that were not included in the 
original issue of the service bulletin. The commenter adds that 
additional work may be required for previously completed work done per 
the original issue of the service bulletin. The commenter considers 
that accomplishment of Revision 1 of the service bulletin will ensure 
that all life-limited parts are tracked and will prevent unnecessary 
requests for alternative methods of compliance.
    The FAA concurs with the request to cite Revision 1 of the 
previously referenced service bulletin, which adds additional spares 
part numbers that were not included in the original issue of Boeing 
Service Bulletin 737-32-1322, dated September 30, 1999, as cited in the 
original NPRM. In response, we have revised paragraphs (a), (b), (c), 
(d), and (f) of this supplemental NPRM accordingly.

Requests To Revise Paragraphs (e) and (f) of the Original NPRM

    Several commenters request revising paragraphs (e) and (f) of the 
original NPRM for several reasons:
    [sbull] One commenter suggests clarifying that the requirements of 
those paragraphs apply only to those airplane models specified in the 
Boeing service bulletin and in the applicability of the original NPRM. 
As presently stated, the requirements could be misconstrued to apply to 
all makes and models.
    [sbull] A second commenter suggests revising paragraphs (e) and (f) 
of the original NPRM to specify that only ``safe-life'' landing gear 
parts are identified in the Boeing service bulletin.
    [sbull] Another commenter suggests revising paragraph (e) of the 
original NPRM to add the words ``life-limited'' landing gear part 
because all components of the landing gear are not life-limited, and do 
not require tracking. (The FAA infers that the suggestion also would 
apply to paragraph (f) of the original NPRM.)
    We concur with the requests to revise paragraphs (e) and (f) of the 
original NPRM. Those paragraphs are revised in the supplemental NPRM to 
specify that ``* * * no person shall install on any Model 737-100, -
200, -200C, -300, -400, and -500, line numbers 1 through 3132 
inclusive, a life-limited landing gear part unless * * *.''

Request To Change a Service Information Reference

    One commenter requests changing paragraph (f) of the original NPRM 
to reference ``737 Type Certificate Data Sheet A1WE'' instead of Boeing 
Service Bulletin 737-32-1322, dated September 30, 1999. The commenter 
contends that the service bulletin includes an incomplete list of life-
limited landing gear parts, but the type certificate data sheet 
provides landing gear life limits and a reference to a detailed list of 
life-limited components.
    We partially concur with the request to change the service 
information reference in paragraph (f) of the original NPRM. However, 
we do not concur that the previously referenced type certificate data 
sheet should be cited instead of the service bulletin in paragraph (f) 
of the supplemental NPRM. We point out that the proposed AD does not 
change the requirements for all of the life-limited landing gear parts 
cited in the data sheet, but only for certain specified parts. However, 
as described previously, this supplemental NPRM has been revised to 
cite Revision 1 instead of the original issue of the service bulletin. 
Paragraph (f) of the supplemental NPRM is changed accordingly.

Requests To Withdraw Proposed Rule

    The Air Transport Association (ATA) of America, on behalf of two of 
its member airlines, requests withdrawal of the original NPRM. The 
commenters contend that the requirements in the original NPRM already 
exist in other regulations (e.g., FAR 121.380), which provide an 
equivalent level of safety for all fleets, including Model 737. The 
commenters state that they previously have complied with the intent of 
the service bulletin. In addition, one of the commenters states that 
the time required for the original NPRM process, and for development of 
the service data, indicate that the problem is not urgent, and 
therefore the NPRM is not needed.
    We do not concur that the original NPRM should be withdrawn. We 
consider that issuance of the proposed supplemental NPRM is necessary 
to include the life-limited parts that were not included in the 
original NPRM. Issuance will ensure that operators add serial numbers 
and track the specified parts. No change to the supplemental NPRM is 
necessary in this regard.

Request To Remove ``Unsafe'' From Note 1 in the Original NPRM

    One commenter requests deleting the word ``unsafe'' from Note 1 in 
the original NPRM. The commenter contends that the condition addressed 
by the original NPRM, and by Revision 1 of the previously referenced 
service bulletin, is a compliance issue. As such, life-limited 
components are required to be tracked and removed from service when the 
specified life limit is reached. Revision 1 of the service bulletin 
identifies parts that previously should have been identified as life-
limited, and provides procedures to ensure that operators comply with 
the requirements for adding serial numbers and tracking those parts. In 
addition, the commenter is not aware that any condition addressed by 
the original NPRM has resulted in the failure of any landing gear 
components, or has created an unsafe condition.
    We do not concur that the word ``unsafe'' should be removed from 
the text of Note 1 of the original NPRM. The supplemental NPRM 
addresses a potential problem that would be unsafe: using life-limited 
landing gear parts beyond their safe-life limitations. No change to 
Note 1 in the supplemental NPRM is necessary in this regard.

Request To Clarify Requirements for Life-Limited Parts

    One commenter requests clarification of the requirements in the 
original NPRM for life-limited parts. The commenter states that the 
original NPRM requires the actions specified in the original issue of 
Service Bulletin 737-32-1322, dated September 30, 1999. That service 
bulletin cites additional life-limited parts that were not previously 
listed in Boeing Drawing

[[Page 60198]]

65C73761, ``737 Main Landing Gear Components,'' and Boeing Drawing 
65C73762, ``737 Nose Landing Gear Components.'' The commenter considers 
that the original NPRM applies only to the life-limited parts listed in 
the service bulletin and not to those listed in Boeing Service Letter 
32-18D, dated December 22, 1999. The commenter also states that, 
because it has tracked each life-limited part listed in the service 
letter since 1996, such action meets the requirements of the original 
NPRM. The FAA infers that the service letter includes more life-limited 
parts than the service bulletin.
    We do not concur that accomplishment of the actions specified in 
the service letter meets the requirements of the supplemental NPRM. 
However, we note that the requirements in the supplemental NPRM are 
limited only to the life-limited parts specified in Revision 1 of the 
service bulletin. No change to the supplemental NPRM is necessary in 
this regard. As discussed earlier, the supplemental NPRM cites Revision 
1 of the service bulletin instead of the original issue.

Request To Revise the Parts Requirements

    One commenter requests revising the parts requirements in the 
original NPRM. The commenter suggests discarding life-limited parts at 
each landing gear overhaul and replacing them with new parts, instead 
of adding serial numbers to the specified parts and tracking those 
parts. The commenter states that, at first overhaul, landing gear parts 
are commonly found beyond economical repair. Therefore, replacing the 
parts would be more economical and would simplify the tracking system.
    We do not concur with the commenter's request to revise the parts 
requirements. We consider that, in order to ensure that parts are not 
used beyond their safe-life limit, it is necessary for operators to 
permanently mark each part and track its service use. However, under 
the provisions of paragraph (g) of the supplemental NPRM, the FAA may 
consider requests for approval of an alternative method of compliance, 
if sufficient data are submitted to substantiate that such an option 
would provide an acceptable level of safety.

Request To Delete Paragraph (d) of the Original NPRM

    One commenter requests deleting paragraph (d) of the original NPRM 
because that paragraph is redundant with existing regulatory 
requirements. The commenter states that the Original Equipment 
Manufacturer has added the parts referenced in Boeing Service Bulletin 
737-32-1322, dated September 30, 1999, in Boeing drawings 65C73761 and 
65C73762, and in Boeing Service Letters 737-SL-32-21 and 737-SL-32-018. 
The commenter contends that the requirements of the proposed AD will 
require operators to maintain two sets of records to track the 
identified parts.
    We do not concur with the request to delete paragraph (d) of this 
supplemental NPRM. We point out that the documents referenced by the 
commenter are not regulatory. Therefore, it is necessary for this 
supplemental NPRM to include a requirement to remove from service a 
specified part that has reached its life limits to ensure regulatory 
compliance. Further, paragraph (d) of the supplemental NPRM does not 
impose any additional recordkeeping requirement for operators. No 
change to the supplemental NPRM is necessary in this regard.

Conclusion

    Since the changes described previously expand the scope of the 
originally proposed rule, the FAA has determined that it is necessary 
to reopen the comment period to provide additional opportunity for 
public comment.

Cost Impact

    There are approximately 3,132 Model 737-100, -200, -200C, -300, -
400, and -500 series airplanes of the affected design in the worldwide 
fleet. The FAA estimates that 1,099 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 1 work 
hour per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
cost impact of the proposed AD on U.S. operators is estimated to be 
$65,940, or $60 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this AD were not adopted. The cost impact 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.

Regulatory Impact

    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, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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 adding the following new 
airworthiness directive:

Boeing: Docket 2000-NM-343-AD.

    Applicability: Model 737-100, -200, -200C, -300, -400, and -500 
series airplanes; certificated in any category; line numbers 1 
through 3132 inclusive.

    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 (g) of 
this AD. The request should include an assessment of

[[Page 60199]]

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 failure of landing gear parts, which could lead to 
landing gear collapse, accomplish the following:

Inspection of Parts and/or Records

    (a) Within 10 years from the effective date of this AD, examine 
records and/or landing gear parts per Boeing Service Bulletin 737-
32-1322, Revision 1, dated September 27, 2001, to determine whether 
parts have serial numbers and whether the number of flight cycles 
for each part has been tracked. If landing gear parts have serial 
numbers, as listed in Boeing Service Bulletin 737-32-1322, Revision 
1, dated September 27, 2001, and the number of flight cycles has 
been tracked, no further action is necessary for paragraphs (a), 
(b), or (c) of this AD.

Assignment of Serial Numbers and Flight Cycles

    (b) If any part examined, as mandated in paragraph (a) of this 
AD, does not have a serial number, within 10 years from the 
effective date of this AD, do the actions required by paragraphs 
(b)(1) and (b)(2) of this AD.
    (1) Assign a serial number to each part per a method approved by 
the Manager, Seattle Aircraft Certification Office (ACO), FAA.
    (2) Mark the serial number on each part per Boeing Service 
Bulletin 737-32-1322, Revision 1, dated September 27, 2001.
    (c) If flight cycles for any part examined, as mandated in 
paragraph (a) of this AD, have not been tracked, within 10 years 
from the effective date of this AD, assign a number of lifetime 
flight cycles to that part per Part 2.B. of the Accomplishment 
Instructions of Boeing Service Bulletin 737-32-1322, Revision 1, 
dated September 27, 2001.

Removal from Service at Life Limit

    (d) When any landing gear part has reached its life-limit number 
of flight cycles, as described in Part 2.B. of the Accomplishment 
Instructions of Boeing Service Bulletin 737-32-1322, Revision 1, 
dated September 27, 2001, before further flight, remove that part 
from service and replace it with a landing gear part having a serial 
number and a lifetime flight cycle number per the service bulletin.

Spare Parts

    (e) As of the effective date of this AD, no person shall install 
on any airplane a life-limited landing gear part unless it has been 
assigned a serial number and a lifetime flight cycle number per the 
requirements of this AD.
    (f) As of the effective date of this AD, no person shall install 
on any airplane a life-limited landing gear part that has reached 
its life limit of flight cycles, per Boeing Service Bulletin 737-32-
1322, Revision 1, dated September 27, 2001.

Alternative Methods of Compliance

    (g) 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, Seattle ACO. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Seattle ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (h) Special flight permits may be issued in accordance with 
Sec. Sec.  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 September 16, 2002.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-24306 Filed 9-24-02; 8:45 am]
BILLING CODE 4910-13-P