[Federal Register Volume 69, Number 25 (Friday, February 6, 2004)]
[Proposed Rules]
[Pages 5771-5773]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-2472]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-109-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all Boeing Model 767 series 
airplanes. This proposal would require repetitive detailed inspections 
of the aft pressure bulkhead for indications of ``oil cans'' and 
previous ``oil can'' repairs, and corrective actions, if necessary. An 
``oil can'' is an area on a pressure dome web that moves when pushed 
from the forward side. This action is necessary to detect and correct 
the propagation of fatigue cracks in the vicinity of ``oil cans'' on 
the web of the aft pressure bulkhead, which could result in rapid 
decompression of the passenger cabin, possible damage or interference 
with the airplane control systems that pass through the bulkhead, and 
consequent loss of control of the airplane. This action is intended to 
address the identified unsafe condition.

DATES: Comments must be received by March 22, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-109-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. 2003-NM-109-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 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplanes, PO Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Suzanne Masterson, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6441; fax (425) 917-6590.

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:
     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.
     For each issue, state what specific change to 
the proposed AD is being requested.
     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

[[Page 5772]]

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 2003-NM-109-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. 2003-NM-109-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report indicating that a 2.1-inch crack in 
the web of the aft pressure bulkhead at the perimeter of an ``oil can'' 
was found on a Model 747 series airplane. An ``oil can'' is an area on 
a pressure dome web that moves when pushed from the forward side. The 
cause of the crack in the web is fatigue. This condition, if not 
detected and corrected, could lead to the propagation of fatigue cracks 
in the vicinity of ``oil cans'' on the web of the aft pressure 
bulkhead, which could result in rapid decompression of the passenger 
cabin, possible damage or interference with the airplane control 
systems that pass through the bulkhead, and consequent loss of control 
of the airplane.
    The aft pressure bulkhead on Model 767 series airplanes is almost 
identical to that on the affected Model 747 series airplanes. 
Therefore, those Model 767 series airplanes may be subject to the 
unsafe condition revealed on the Model 747 series airplanes.

Other Related Rulemaking

    The FAA may consider further rulemaking to address the unsafe 
condition identified on Model 747 series airplanes.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
767-53A0105, dated April 10, 2003; and Boeing Alert Service Bulletin 
767-53A0106, dated April 10, 2003; which describe procedures for 
performing repetitive detailed inspections of the aft pressure bulkhead 
for indications of ``oil cans'' and previous ``oil can'' repairs, and 
corrective actions, if necessary. The corrective actions include 
performing a detailed inspection of the web around any ``oil can'' 
repair for cracks and smaller ``oil cans'' and repairing cracks; and 
performing repetitive high frequency eddy current inspections of the 
web around the periphery of the ``oil can'' indication for cracks and 
repairing cracks. Repair of all ``oil cans'' eliminates the need for 
the repetitive high frequency eddy current inspections.

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 require accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Differences Between Proposed Rule and Service Bulletins

    Operators should note that, although the service bulletins specify 
that the manufacturer may be contacted for disposition of certain 
repair conditions, this proposal would require the repair of those 
conditions to be accomplished per a method approved by the FAA, or per 
data meeting the type certification basis of the airplane approved by a 
Boeing Company Designated Engineering Representative who has been 
authorized by the FAA to make such findings.

Clarification of Actions in Service Bulletins

    Operators should note that paragraph 1.b. of ``Part 3--Inspection 
of `Oil Cans,' '' of the Accomplishment Instructions of Boeing Alert 
Service Bulletin 767-53A0106, dated April 10, 2003, states, `` * * * 
limits shown in 767-200, 767-300, or 767-300F Structural Repair Manual 
(SRM) 53-80-08, Figure 102.'' However, the service bulletin applies to 
Model 767-400ER series airplanes, and thus the reference should be to 
767-400 SRM 53-80-08, Figure 102, as specified in the previous 
paragraph 1.a. of the service bulletin.
    Operators should note that ``Part 2--Inspection of Previous `Oil 
Can' Repairs'' of the Accomplishment Instructions of both service 
bulletins states, ``Do the inspections shown in Part 2 again at the 
time shown in Figure 1.'' However, Figure 1 of the service bulletins 
specifies that the inspection in ``Part 1--Access and Inspection'' is 
to be repeated. We have determined that the correct reference is Part 
1. Therefore this proposed AD would require repetitive inspection per 
Part 1.

Interim Action

    This is considered to be interim action. The FAA may consider 
further rulemaking to reduce thresholds if cracks are reported earlier 
than the predicted fatigue life.

Cost Impact

    There are approximately 890 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 398 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
14 work hours per airplane to accomplish the proposed detailed 
inspection, and that the average labor rate is $65 per work hour. Based 
on these figures, the cost impact of the proposed AD on U.S. operators 
is estimated to be $362,180, or $910 per airplane, per inspection 
cycle.
    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 proposed 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

[[Page 5773]]

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 2003-NM-109-AD.

    Applicability: All Model 767 series airplanes, certificated in 
any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To detect and correct the propagation of fatigue cracks in the 
vicinity of ``oil cans'' on the web of the aft pressure bulkhead, 
which could result in rapid decompression of the passenger cabin, 
possible damage or interference with the airplane control systems 
that pass through the bulkhead, and consequent loss of control of 
the airplane, accomplish the following:

Service Bulletin References

    (a) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of the following service bulletins, as 
applicable:
    (1) For Model 767-200, -300, and -300F series airplanes: Boeing 
Alert Service Bulletin 767-53A0105, dated April 10, 2003; and
    (2) For Model 767-400ER series airplanes: Boeing Alert Service 
Bulletin 767-53A0106, dated April 10, 2003.

Initial and Repetitive Inspections

    (b) Perform a detailed inspection of the aft pressure bulkhead 
for indications of ``oil cans'' and previous ``oil can'' repairs, in 
accordance with the service bulletin, at the applicable time 
specified in paragraph (b)(1) or (b)(2) of this AD. Repeat the 
detailed inspection thereafter at intervals not to exceed 6,000 
flight cycles.

    Note 1: For the purposes of this AD, a detailed inspection is 
defined as: ``An intensive visual examination of a specific 
structural area, system, installation, or assembly to detect damage, 
failure, or irregularity. Available lighting is normally 
supplemented with a direct source of good lighting at intensity 
deemed appropriate by the inspector. Inspection aids such as mirror, 
magnifying lenses, etc., may be used. Surface cleaning and elaborate 
access procedures may be required.''

    (1) For Model 767-200 and -300 series airplanes: Prior to the 
accumulation of 50,000 total flight cycles, or within 1,000 flight 
cycles after the effective date of this AD, whichever is later.
    (2) For Model 767-300F and -400ER series airplanes: Prior to the 
accumulation of 40,000 total flight cycles, or within 1,000 flight 
cycles after the effective date of this AD, whichever is later.

Indication of Previous ``Oil Can'' Repairs

    (c) If any previous ``oil can'' repair is found during any 
detailed inspection required by paragraph (b) of this AD: Before 
further flight, do a detailed inspection of the web around any ``oil 
can'' repair for cracks or smaller ``oil cans,'' in accordance with 
the service bulletin.
    (1) If any crack is found, before further flight, repair in 
accordance with the service bulletin. Where the service bulletin 
specifies to contact Boeing for repair, before further flight, 
repair per a method approved by the Manager, Seattle Aircraft 
Certification Office (ACO), FAA; or per data meeting the type 
certification basis of the airplane approved by a Boeing Company 
Designated Engineering Representative who has been authorized by the 
Manager, Seattle ACO, to make such findings. For a repair method to 
be approved, the approval must specifically reference this AD.
    (2) If any ``oil can'' is found, before further flight, perform 
the surface high frequency eddy current (HFEC) inspection specified 
in paragraph (d) of this AD.

Indication of ``Oil Can''

    (d) If any indication of an ``oil can'' is found during any 
detailed inspection specified in paragraph (b) or (c) of this AD: 
Before further flight, perform a surface HFEC inspection of the web 
around the periphery and in the center of the ``oil can'' indication 
for cracks, at all ``oil cans,'' and perform a detailed inspection 
of the web for cracks, in accordance with the service bulletin. 
Alternative inspection specified in the service bulletin is 
acceptable for this AD.
    (1) If no crack is found and the ``oil can'' meets the allowable 
limits specified in the service bulletin, do the action in either 
paragraph (d)(1)(i) or (d)(1)(ii) of this AD.
    (i) Repeat the surface HFEC inspection specified in paragraph 
(d) of this AD thereafter at intervals not to exceed 3,000 flight 
cycles.
    (ii) Before further flight, repair the ``oil can'' in accordance 
with the service bulletin. Repair of all ``oil cans'' is considered 
a terminating action for the repetitive HFEC inspections required by 
paragraph (d)(1)(i) of this AD. However, continue to repeat the 
detailed inspection required by paragraph (b) of this AD.
    (2) If no crack is found and the ``oil can'' does not meet the 
specified allowable limits specified in the service bulletin: Before 
further flight, repair the ``oil can'' in accordance with the 
service bulletin. If, following the repair, any ``oil can'' remains 
that meets the allowable limits specified in the service bulletin, 
do the action required by either paragraph (d)(1)(i) or (d)(1)(ii) 
of this AD.
    (3) If any crack is found, before further flight, repair in 
accordance with the service bulletin. Where the service bulletin 
specifies to contact Boeing for appropriate action, before further 
flight, repair per a method approved by the Manager, ACO, FAA; or 
per data meeting the type certification basis of the airplane 
approved by a Boeing Company Designated Engineering Representative 
who has been authorized by the Manager, Seattle ACO, to make such 
findings. For a repair method to be approved, the approval must 
specifically reference this AD.

Alternative Methods of Compliance

    (e) In accordance with 14 CFR 39.19, the Manager, Seattle ACO, 
FAA, is authorized to approve alternative methods of compliance for 
this AD.

    Issued in Renton, Washington, on January 29, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-2472 Filed 2-5-04; 8:45 am]
BILLING CODE 4910-13-P