[Federal Register Volume 60, Number 111 (Friday, June 9, 1995)]
[Proposed Rules]
[Pages 30474-30476]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-14169]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-184-AD]


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 all British Aerospace Model BAC 1-
11 200 and 400 series airplanes. This proposal would require various 
repetitive inspections to detect cracks in certain panels of the lower 
skin of the wing, and in certain fixed ribs of the leading edge of the 
wing. This proposal would also require repair or replacement of cracked 
parts, which would terminate certain repetitive inspections. This 
proposal is prompted by reports of cracking in certain panels of the 
lower skin of the wing, and in certain fixed ribs of the leading edge 
of the wing due to fatigue-related stress. The actions specified by the 
proposed AD are intended to ensure the structural integrity of the wing 
by detecting fatigue-related cracking in a timely manner in the panels 
of the lower skin of the wing or in the fixed ribs of the leading edge 
of the wing.

DATES: Comments must be received by July 21, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-184-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: William Schroeder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2148; fax (206) 227-1149. [[Page 30475]] 

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 94-NM-184-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. 94-NM-184-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 all British Aerospace Model BAC 1-11 200 
and 400 series airplanes. The CAA advises that it has received reports 
of cracking in panel number 1 at rib 6 of the lower skin of the wing on 
these airplanes that had accumulated 17,000 to 42,000 total flight 
cycles. Cracking was also found in the panel number 2 at rib 10 of the 
lower skin of the wing on these airplanes that had accumulated 45,000 
to 53,000 total flight cycles. Furthermore, cracking was found in fixed 
ribs 6, 10, and 14 of the leading edge of the wing. Investigation 
revealed that the cause of this cracking has been attributed to 
fatigue-related stress. Fatigue-related cracking in the panels of the 
lower skin of the wing or in the fixed ribs of the leading edge of the 
wing, if not detected and corrected in a timely manner, could reduce 
the structural integrity of the wing.
    British Aerospace has issued Alert Service Bulletin 57-A-PM5992, 
Issue 1, dated October 14, 1992, which describes procedures for various 
repetitive inspections to detect cracks in panel number 1 at rib 6 and 
in panel number 2 at rib 10 of the lower skin of the wing, in the 
rebate radius of panel number 2 at the joint between panels 1 and 2 of 
the lower skin of the wing, and in the top and bottom flanges of fixed 
ribs 6, 10, and 14 of the leading edge of the wing. This alert service 
bulletin also describes procedures for repair or replacement of cracked 
parts, which would eliminate the need for certain repetitive 
inspections. The CAA classified this alert service bulletin as 
mandatory in order to assure the continued airworthiness of these 
airplanes in the United Kingdom.
    This airplane model is manufactured in the United Kingdom and is 
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.
    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 various repetitive 
inspections to detect cracks in panel number 1 at rib 6 and in panel 
number 2 at rib 10 of the lower skin of the wing, in the rebate radius 
of panel number 2 at the joint between panels 1 and 2 of lower skin of 
the wing, and in the top and bottom flanges of fixed ribs 6, 10, and 14 
of the leading edge of the wing. This proposed AD would also require 
repair or replacement of cracked parts, which would constitute 
terminating action for certain repetitive inspection requirements. The 
actions would be required to be accomplished in accordance with the 
alert service bulletin described previously. If any cracks are detected 
at rib 10, the repair of panel number 2 would be required to be 
accomplished in accordance with a method approved by the FAA.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been included in this notice to clarify this long standing requirement.
    The FAA estimates that 31 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 actions, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
total cost impact of the proposed AD on U.S. operators is estimated to 
be $26,040, or $840 per airplane.
    The total 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 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 [[Page 30476]] 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


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 94-NM-184-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 use the authority 
provided in paragraph (d) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure the structural integrity of the wing, accomplish the 
following:
    (a) Prior to the accumulation of 12,000 total landings or within 
1,500 landings after the effective date of this AD, whichever occurs 
later, perform a close visual and dye penetrant inspection to detect 
cracks in panel number 1 at rib 6 and in panel number 2 at rib 10 of 
the lower skin of the wing, in accordance with British Aerospace 
Alert Service Bulletin 57-A-PM5992, Issue 1, dated October 14, 1992.
    (1) If no crack is detected, repeat the inspections thereafter 
at intervals not to exceed 8,000 landings.
    (2) If any crack is detected at rib 6, prior to further flight, 
repair panel number 1 in accordance with the alert service bulletin. 
Accomplishment of this repair constitutes terminating action for the 
repetitive inspections of panel number 1 as required by this 
paragraph.
    (3) If any crack is detected at rib 10, prior to further flight, 
repair panel number 2 in accordance with a method approved by the 
Manager, Standardization Branch, ANM-113, FAA, Transport Airplane 
Directorate.
    (b) Prior to the accumulation of 30,000 total landings or within 
1,500 landings after the effective date of this AD, whichever occurs 
later, perform an eddy current inspection to detect cracks in the 
rebate radius of panel number 2 at the joint between panels 1 and 2 
of lower skin of the wing, in accordance with British Aerospace 
Alert Service Bulletin 57-A-PM5992, Issue 1, dated October 14, 1992.
    (1) If no crack is detected, repeat the inspection thereafter at 
intervals not to exceed 8,000 landings.
    (2) If any crack is detected, prior to further flight, repair 
panel number 2 in accordance with the alert service bulletin. 
Accomplishment of this repair constitutes terminating action for the 
repetitive inspections of panel number 2 as required by this 
paragraph.
    (c) Prior to the accumulation of 30,000 total landings or within 
1,500 landings after the effective date of this AD, whichever occurs 
later, perform a close visual inspection to detect cracks in the top 
and bottom flanges of fixed ribs 6, 10, and 14 of the leading edge 
of the wing, in accordance with British Aerospace Alert Service 
Bulletin 57-A-PM5992, Issue 1, dated October 14, 1992.
    (1) If no crack is detected, repeat the inspection thereafter at 
intervals not to exceed 8,000 landings.
    (2) If any crack is detected, prior to further flight, replace 
the cracked rib with a new rib, in accordance with the alert service 
bulletin. Prior to the accumulation of 30,000 total landings on the 
newly installed rib, perform a close visual inspection to detect 
cracks on the newly installed rib in accordance with the service 
bulletin. Repeat the inspection thereafter at intervals not to 
exceed 8,000 landings.
    (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 June 5, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-14169 Filed 6-8-95; 8:45 am]
BILLING CODE 4910-13-U