[Federal Register Volume 62, Number 57 (Tuesday, March 25, 1997)]
[Proposed Rules]
[Pages 14047-14048]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-7518]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-193-AD]
RIN 2120-AA64


Airworthiness Directives; British Aerospace Model BAC 1-11 200 
and 400 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 certain British Aerospace Model 
BAC 1-11 200 and 400 series airplanes. This proposal would require 
inspections of the main landing gear (MLG) A-frame attachment fittings 
to detect corrosion or cracking, and repair or replacement of cracked 
or corroded components with new components. This proposal is prompted 
by findings of corroded and cracked A-frame components of the MLG. The 
actions specified by the proposed AD are intended to prevent corrosion 
and cracking of MLG A-frame components, which could result in collapse 
of the MLG.

DATES: Comments must be received by May 5, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-193-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 British Aerospace, Airbus Limited, P.O. Box 77, Bristol 
BS99 7AR, England. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Tim Backman, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2797; fax (206) 227-1149.

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 96-NM-193-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-103, Attention: Rules 
Docket No. 96-NM-193-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for the United Kingdom, recently notified the FAA that an 
unsafe condition may exist on certain British Aerospace Model BAC 1-11 
200 and 400 series airplanes. The CAA advises that, during regular 
inspections for corrosion, several cases of cracks were found in the 
main landing gear (MLG) A-frame attachment fittings of airplanes that 
had accumulated between 32,000 and 43,000 landings. Laboratory 
investigation of cracked components revealed that cracks occurred as a 
result of stress corrosion. The cracks initiated in the bores of the 
lugs and propagated to the outside radii. This condition, if not 
corrected, could result in collapse of the MLG.

Explanation of Relevant Service Information

    British Aerospace has issued Alert Service Bulletin 53-A-PM6036, 
Issue 1, dated November 24, 1995, which describes procedures for 
repetitive detailed visual inspections of MLG A-frame attachment 
fittings to detect corrosion or cracking. The alert service bulletin 
also provides procedures for either repair or replacement of cracked or 
corroded components with new components. The CAA classified the alert 
service bulletin as mandatory in order to assure the continued 
airworthiness of these airplanes in the United Kingdom.

FAA's Conclusions

    These airplane models are manufactured in the United Kingdom and 
are type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement. Pursuant 
to this bilateral airworthiness agreement, the CAA has kept the FAA 
informed of the situation described above. The FAA has examined the 
findings of the CAA, reviewed all available information, and determined 
that AD action is necessary for products of this type design that are 
certificated for operation in the United States.

[[Page 14048]]

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require repetitive detailed 
visual inspections of the MLG A-frame attachment fittings to detect 
corrosion or cracking, and repair or replacement of cracked or corroded 
components with new components. The actions would be required to be 
accomplished in accordance with the alert service bulletin described 
previously.

Cost Impact

    The FAA estimates that 25 Model BAC 1-11 200 and 400 series 
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 $1,500, or $60 per airplane, per 
inspection.
    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.

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 adding the following new 
airworthiness directive:

British Aerospace Airbus Limited (Formerly British Aerospace 
Commercial Aircraft Limited, British Aerospace Aircraft Group): 
Docket 96-NM-193-AD.

    Applicability: Model BAC 1-11 200 and 400 series airplanes; 
equipped with main landing gear (MLG) A-frame attachment fittings 
having the part numbers listed in British Aerospace Alert Service 
Bulletin 53-A-PM6036, Issue 1, dated November 24, 1995; certificated 
in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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) 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 corrosion or cracking of MLG A-frame fittings, which 
could result in collapse of the MLG, accomplish the following 
actions.
    (a) Conduct a detailed visual inspection to detect corrosion or 
cracking of the MLG A-frame attachment fittings, in accordance with 
British Aerospace Alert Service Bulletin 53-A-PM6036, Issue 1, dated 
November 24, 1995, and at the applicable time specified in paragraph 
(a)(1) or (a)(2) of this AD:
    (1) For airplanes that have accumulated 16,000 or fewer total 
landings as of the effective date of this AD: Conduct the initial 
inspection at the later of the times specified in paragraphs 
(a)(1)(i) and (a)(1)(ii).
    (i) Prior to the accumulation of 16,000 total landings or within 
8 years since new, whichever occurs first; or
    (ii) Within 6 months after the effective date of this AD.
    (2) For airplanes that have accumulated more than 16,000 total 
landings as of the effective date of this AD: Conduct the initial 
inspection within 4,000 landings or 2 years after the effective date 
of this AD, whichever occurs first.
    (b) If no corrosion or cracking is found, repeat the inspection 
required by paragraph (a) of this AD thereafter at intervals of 
4,000 landings or 2 years, whichever occurs first.
    (c) If corrosion is found and it is within the limits specified 
in British Aerospace Alert Service Bulletin 53-A-PM6036, Issue 1, 
dated November 24, 1995, prior to further flight, repair the 
component in accordance with the alert service bulletin. After 
repair, repeat the inspection required by paragraph (a) of this AD 
thereafter at intervals of 4,000 landings or 2 years, whichever 
occurs first.
    (d) If corrosion is found and it is outside the limits specified 
in British Aerospace Alert Service Bulletin 53-A-PM6036, Issue 1, 
dated November 24, 1995, prior to further flight, replace the 
corroded component with a new component in accordance with the alert 
service bulletin. After replacement, repeat the inspection required 
by paragraph (a) of this AD thereafter at intervals of 4,000 
landings or 2 years, whichever occurs first.
    (e) If any cracking is found, prior to further flight, replace 
the cracked component with a new component in accordance with 
British Aerospace Alert Service Bulletin 53-A-PM6036, Issue 1, dated 
November 24, 1995. After replacement, repeat the inspection required 
by paragraph (a) of this AD thereafter at intervals of 4,000 
landings or 2 years, whichever occurs first.
    (f) 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, Standardization Branch, ANM-113, 
FAA, Transport Airplane Directorate. Operators shall submit their 
requests through an appropriate FAA Principal Maintenance Inspector, 
who may add comments and then send it to the Manager, 
Standardization Branch, ANM-113.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (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 19, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-7518 Filed 3-24-97; 8:45 am]
BILLING CODE 4910-13-U