[Federal Register Volume 62, Number 31 (Friday, February 14, 1997)]
[Proposed Rules]
[Pages 6892-6894]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-3696]


-----------------------------------------------------------------------


DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 96-NM-188-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).

-----------------------------------------------------------------------

SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all British Aerospace Model BAC 1-
11 200 and 400 series airplanes. This proposal would require repetitive 
ultrasonic inspections to detect cracking of the lugs of the engine 
mounting beams, and replacement of the beam with a serviceable part, if 
necessary. This proposal is prompted by reports of fatigue cracking of 
the lugs of the engine mounting beams. The actions specified by the 
proposed AD are intended to detect and correct such cracking of the 
engine mounting lugs, which could result in reduced structural 
capability of the engine mount.

DATES: Comments must be received by March 27, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-188-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-188-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-188-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Civil Aviation Authority (CAA), which is the airworthiness 
authority for

[[Page 6893]]

the United Kingdom, recently notified the FAA that an unsafe condition 
may exist on all British Aerospace Model BAC 1-11 200 and 400 series 
airplanes. The CAA advises that it has received two reports of fatigue 
cracking of the upper rear engine mounting beam. In one instance, the 
airplane had accumulated 11,344 flight hours and logged 6,267 landings. 
In the other instance, the airplane had accumulated 1,740 flight hours 
and logged 858 landings. In the latter instance, the crack of the lug 
had opened sufficiently to be detected visually and had propagated in 
the longitudinal direction of the beam from the bore to the outside 
edge of the lug. Such cracking of the lugs of the engine mounting beam, 
if not detected and corrected, could result in reduced structural 
capability of the engine mount.

Explanation of Relevant Service Information

    British Aerospace has issued Alert Service Bulletin 53-A-PM6032, 
Issue 1, dated April 7, 1995, which describes procedures for repetitive 
ultrasonic inspections to detect cracking of the lugs of the lower 
forward, lower rear, upper forward, and upper rear engine mounting 
beams, and replacement of the beam with a serviceable part, if 
necessary. The CAA classified this service bulletin as mandatory in 
order to assure the continued airworthiness of these airplanes in the 
United Kingdom.

FAA's Conclusions

    This airplane model is manufactured in the United Kingdom and is 
type certificated for operation in the United States under the 
provisions of Sec. 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.

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 
ultrasonic inspections to detect cracking of the lugs of the lower 
forward, lower rear, upper forward, and upper rear engine mounting 
beams, and replacement of the beam with a serviceable part, if 
necessary. The actions would be required to be accomplished in 
accordance with the alert service bulletin described previously.
    Operators should note that certain compliance times in the proposed 
AD are specified in landings or flight hours, as well as calendar time. 
The FAA has determined that, since fatigue cracking is directly related 
to the number of landings, the compliance times should be specified in 
landings that are based on the earliest number of landings known to 
have been completed when cracking of the lugs of the engine mounting 
beams were detected.

Cost Impact

    The FAA estimates that 31 British Aerospace 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 6 work hours 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 $11,160 or $360 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.

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-188-AD.

    Applicability: All Model BAC 1-11 200 and 400 series airplanes, 
certificated in any category.

    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 (d) 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 detect and correct cracking of the engine mounting lugs, 
which could result in reduced structural capability of the engine 
mount; accomplish the following:
    (a) Perform an ultrasonic inspection to detect cracking of the 
lugs of the lower forward, lower rear, upper forward, and upper rear 
of the engine mounting beams in accordance with British Aerospace 
Alert Service Bulletin 53-A-PM6032, Issue 1, dated April 7, 1995, 
and at the earliest of the times specified in paragraph (a)(1), 
(a)(2), or (a)(3) of this AD.
    (1) Within 850 landings after the effective date of this AD. Or
    (2) Within 1,700 flight hours after the effective date of this 
AD. Or
    (3) Within 2 years after the effective date of this AD.
    (b) If no cracking is detected, repeat the inspection thereafter 
at intervals not to

[[Page 6894]]

exceed 1,700 flight hours or 850 landings, whichever occurs first.
    (c) If any cracking is detected, prior to further flight, 
replace the engine mounting beam in accordance with British 
Aerospace Alert Service Bulletin 53-A-PM6032, Issue 1, dated April 
7, 1995.
    (d) 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.

    (e) 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 February 7, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-3696 Filed 2-13-97; 8:45 am]
BILLING CODE 4910-13-U