
[Federal Register: August 21, 2008 (Volume 73, Number 163)]
[Proposed Rules]               
[Page 49366-49368]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21au08-16]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0898; Directorate Identifier 2007-NM-200-AD]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 767-200 and 767-300 Series 
Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Boeing Model 767-200 and 767-300 series airplanes. This 
proposed AD would require detailed inspections of the aft pressure 
bulkhead for damage, mid-frequency eddy current (MFEC) and low 
frequency eddy current (LFEC) inspections of radial web lap splices, 
tear strap splices, and super tear strap splices for cracking, and 
corrective actions if necessary. This AD results from analysis that 
indicates fatigue cracks of the web lap splice, tear strap splice, or 
super tear strap splice of the aft bulkhead are expected to occur on 
certain Boeing Model 767-200 and 767-300 series airplanes. We are 
proposing this AD to detect and correct fatigue cracks of the aft 
pressure bulkhead, which could result in rapid decompression of the 
passenger compartment and possible damage or interference with airplane 
control systems that penetrate the bulkhead, and consequent loss of 
controllability of the airplane.

DATES: We must receive comments on this proposed AD by October 6, 2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Tamara L. Anderson, Aerospace 
Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6421; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0898; 
Directorate Identifier 2007-NM-200-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each

[[Page 49367]]

substantive verbal contact we receive about this proposed AD.

Discussion

    We have previously issued AD 2005-03-11, amendment 39-13967 (70 FR 
7174, February 11, 2005). (A correction of the rule was published in 
the Federal Register on March 11, 2005 (70 FR 12119, March 11, 2005).) 
That AD applies to certain Boeing Model 767-200 and 767-300 series 
airplanes, line numbers 1 through 175 inclusive. That AD was prompted 
by a report of multiple-site fatigue cracking (multiple-site damage) in 
two lap splices on the aft pressure bulkhead of one airplane. That AD 
currently requires repetitive detailed and eddy current inspections of 
the aft pressure bulkhead for damage and cracking, one-time detailed 
and high frequency eddy current inspections of any ``oil can'' located 
on the aft pressure bulkhead for damage and cracking, and related 
corrective actions if necessary.
    Since the issuance of that AD, analysis indicates that fatigue 
cracks of the web lap splice, tear strap splice, or super tear strap 
splice of the aft bulkhead are expected to occur on Boeing Model 767-
200 and 767-300 series airplanes having line numbers 176 through 423 
inclusive that have accumulated 35,000 or more total flight cycles. 
There have been no reports of such fatigue cracks on these in-service 
airplanes. Such fatigue cracking, if not corrected, could result in 
rapid decompression of the passenger compartment and possible damage or 
interference with airplane control systems that penetrate the bulkhead, 
and consequent loss of controllability of the airplane.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 767-53A0147, dated 
August 16, 2007. The service bulletin describes procedures for:
     Doing an initial detailed inspection of the aft pressure 
bulkhead for damage such as dents, punctures, nicks, gouges, cracks, 
corrosion, and scratches, and repeating those inspections.
     Doing initial mid-frequency eddy current (MFEC) and low-
frequency eddy current (LFEC) inspections of the radial web lap 
splices, tear strap splices, and super tear strap splices for cracking, 
and repeating those inspections.
     Contacting Boeing for inspection instructions where 
inspection is prevented by a repair common to the inspection area.
     Doing applicable corrective actions, which include 
repairing any damage that exceeds certain allowable limits, and 
contacting Boeing for repair instructions. The service bulletin 
specifies the following compliance times:
     For the initial inspections: 35,000 total flight-cycles, 
or 18 months or 3,000 flight-cycles after the date of the service 
bulletin, whichever occurs first.
     For the repetitive inspections: Within 3,000 flight-cycles 
of the initial inspection, and thereafter at intervals not to exceed 
3,000 flight-cycles.
     For the applicable corrective actions: Before further 
flight.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other airplanes 
of this same type design. For this reason, we are proposing this AD, 
which would require accomplishing the actions specified in the service 
information described previously, except as discussed under 
``Differences Between Proposed Rule and Service Bulletin.''

Differences Between Proposed Rule and Service Bulletin

    The service bulletin specifies to contact the manufacturer for 
instructions on how to repair and inspect certain conditions, but this 
proposed AD would require repairing and inspecting those conditions in 
one of the following ways:
     Using a method that we approve; or
     Using data that meet the certification basis of the 
airplane, and that have been approved by an Authorized Representative 
for the Boeing Commercial Airplanes Delegation Option Authorization 
Organization whom we have authorized to make those findings.

Clarification of Repetitive Inspections Specified in Service Bulletin

    The Accomplishment Instructions of the service bulletin specifies 
to only repeat the inspections if no crack is found. However, Table 2 
of paragraph 1.E, ``Compliance,'' of the service bulletin identifies 
repeat intervals for the inspections, regardless of inspection 
findings. The intent is that the inspections be repeated for all 
findings. Therefore, this proposed AD would require repetitive 
inspections at the applicable repeat intervals listed in Table 2 of 
paragraph 1.E., ``Compliance.''

Costs of Compliance

    There are about 244 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 84 airplanes of 
U.S. registry. The proposed actions would take about 31 work hours per 
airplane, at an average labor rate of $80 per work hour. Based on these 
figures, the estimated cost of the proposed AD for U.S. operators is 
$208,320, or $2,480 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 proposed AD 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.

[[Page 49368]]

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-2008-0898; Directorate Identifier 2007-NM-
200-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by October 
6, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 767-200 and 767-300 series 
airplanes, certificated in any category; as identified in Boeing 
Alert Service Bulletin 767-53A0147, dated August 16, 2007.

Unsafe Condition

    (d) This AD results from analysis that indicates fatigue cracks 
of the web lap splice, tear strap splice, or super tear strap splice 
of the aft bulkhead are expected to occur on certain Boeing Model 
767-200 and 767-300 series airplanes. We are proposing this AD to 
detect and correct fatigue cracks of the aft pressure bulkhead, 
which could result in rapid decompression of the passenger 
compartment and possible damage or interference with airplane 
control systems that penetrate the bulkhead, and consequent loss of 
controllability of the airplane.

Compliance

    (e) Comply with this AD within the compliance times specified, 
unless already done.

Inspections and Applicable Related Investigative and Corrective Actions

    (f) Except as provided by paragraphs (f)(1) and (f)(2) of this 
AD: At the applicable compliance time and repeat intervals listed in 
Tables 1 and 2 of paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 767-53A0147, dated August 16, 2007, do detailed 
inspections of the aft pressure bulkhead for damage, mid-frequency 
eddy current (MFEC) and low-frequency eddy current (LFEC) 
inspections of radial web lap splices, tear strap splices, and super 
tear strap splices for cracking and applicable corrective actions by 
accomplishing all the applicable actions specified in the 
Accomplishment Instructions of the service bulletin.
    (1) Where Table 1 of paragraph 1.E., ``Compliance,'' of the 
service bulletin specifies a compliance time after the date on the 
service bulletin, this AD requires compliance within the specified 
compliance time after the effective date of this AD.
    (2) Where the service bulletin specifies a compliance time of 
``As given by Boeing'' or to contact Boeing for the appropriate 
action, this AD requires, before further flight, inspections of the 
area of repair and repair of any damaged/cracked part, as 
applicable, using a method approved in accordance with the 
procedures specified in paragraph (g) of this AD.

Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, ATTN: Tamara L. Anderson, Aerospace Engineer, Airframe Branch, 
ANM-120S, 1601 Lind Avenue, SW., Renton, Washington, telephone (425) 
917-6421; fax (425) 917-6590; has the authority to approve AMOCs for 
this AD, if requested using the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane and the approval must specifically refer to this AD.

    Issued in Renton, Washington, on August 8, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E8-19363 Filed 8-20-08; 8:45 am]

BILLING CODE 4910-13-P
