[Federal Register Volume 61, Number 131 (Monday, July 8, 1996)]
[Proposed Rules]
[Pages 35693-35695]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-17295]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-CE-103-AD]


Airworthiness Directives; Aerospace Technologies of Australia Pty 
Ltd. (formerly Government Aircraft Factory) Models N22B, N24A, and N22S 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to adopt a new airworthiness directive 
(AD) that would apply to Aerospace Technologies of Australia Pty Ltd. 
(ASTA) Models N22B, N24A, and N22S airplanes that are not equipped with 
a part number (P/N) 1E/N-12-57 fuselage stub fin plate (MOD N759). The 
proposed action would require replacing the existing fuselage stub fin 
plate with one of improved design, P/N 1E/N-12-57. Several reports of 
cracks along the forward flange of the fuselage stub fin plate in the 
area of Rib Water Line (WL) 138.87 prompted the proposed action. The 
actions specified by the proposed AD are intended to prevent structural 
failure of the fuselage area caused by a cracked stub fin plate, which, 
if not detected and corrected, could result in loss of control of the 
airplane.

DATES: Comments must be received on or before September 6, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 95-CE-103-AD, Room 1558, 601 E. 
12th Street, Kansas City, Missouri 64106. Comments may be inspected at 
this location between 8 a.m. and 4 p.m., Monday through Friday, 
holidays excepted.

ADDRESSES: Service information that applies to the proposed AD may be 
obtained from Aerospace Technologies of Australia Pty Ltd., ASTA 
DEFENCE, Private Bag No. 4, Beach Road Lara 3212, Victoria, Australia. 
This information also may be examined at the Rules Docket at the 
address below. Send comments on the proposal in triplicate to the 
Federal Aviation Administration (FAA), Central Region, Office of the 
Assistant Chief Counsel, Attention: Rules Docket No. 95-CE-103-AD, Room 
1558, 601 E. 12th Street, Kansas City, Missouri 64106. Comments may be 
inspected at this location between 8 a.m. and 4 p.m., Monday through 
Friday, holidays excepted.

FOR FURTHER INFORMATION CONTACT: Mr. Ron Atmur, Aerospace Engineer, 
FAA, Los Angeles Aircraft Certification Office, 3960 Paramount 
Boulevard, Lakewood, California 90712; telephone (310) 627-5224; 
facsimile (310) 627-5210.

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 should 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 that summarizes 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 No. 95-CE-103-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, Central Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket No. 95-CE-103-AD, Room 1558, 601 E. 12th 
Street, Kansas City, Missouri 64106.

Discussion

    The Civil Aviation Safety Authority (CASA), which is the 
airworthiness authority for Australia, recently notified the FAA that 
an unsafe condition may

[[Page 35694]]

exist on certain ASTA Models N22B, N24A, and N22S airplanes. The CASA 
reports several incidents of cracks along the forward flange of the 
fuselage stub fin plate in the area of Rib Water Line (WL) 138.87. 
Investigation has revealed fretting and fatigue of this plate, part 
number (P/N) 1D/N-12-57. These conditions, if not detected and 
corrected, could result in structural failure of the fuselage area, 
which could result in loss of control of the airplane.
    ASTA has issued Nomad Service Bulletin (SB) ANMD- 53-13, Revision 
3, dated October 24, 1995, which specifies procedures for installing a 
fuselage stub fin plate of improved design, P/N 1E/N-12-57.
    The CASA of Australia classified this service bulletin as mandatory 
and issued FCAA AD/GAF-N22/63, amendment 1, dated July 1994, in order 
to assure the continued airworthiness of these airplanes in Australia.
    This airplane model is manufactured in Australia 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 CASA of Australia has kept the 
FAA informed of the situation described above. The FAA has examined the 
findings of the CASA of Australia, reviewed all available information 
including the service information referenced above, and determined that 
AD action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of the Provisions of the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other ASTA Models N22B, N24A, and N22S airplanes of 
the same type design that are registered in the United States and are 
not equipped with a P/N 1E/N-12-57 fuselage stub fin plate (MOD N759), 
the proposed AD would require replacing the existing fuselage stub fin 
plate with one of improved design, P/N 1E/N-12-57. Accomplishment of 
the proposed installation would be in accordance with Nomad SB ANMD-53-
13, Revision 3, dated October 24, 1995.

Cost Impact

    The FAA estimates that 15 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 22 
workhours per airplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts cost 
approximately $150 per airplane. Based on these figures, the total cost 
impact of the proposed AD on U.S. operators is estimated to be $22,050 
or $1,470 per airplane. This figure is based on the assumption that no 
affected owner/operator of the affected airplanes has accomplished the 
proposed replacement.
    ASTA has informed the FAA that it has no records of parts 
distribution. The FAA believes that several of the affected airplanes 
already have the proposed replacement incorporated, which would reduce 
the cost impact upon the public.

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 action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under 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 has been placed 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), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
(AD) to read as follows:

Aerospace Technologies of Australia PTY Ltd: Docket No. 95-CE-103-
AD.

    Applicability: Models N22B, N24A, and N22S airplanes (all serial 
numbers), certificated in any category, that are not equipped with a 
part number (P/N) 1E/N-12-57 fuselage stub fin plate (MOD N759).

    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 (c) 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 within the next 100 hours time-in-service 
after the effective date of this AD, unless already accomplished.
    To prevent structural failure of the fuselage area caused by a 
cracked stub fin plate, which, if not detected and corrected, could 
result in loss of control of the airplane, accomplish the following:
    (a) Replace the fuselage stub fin plate with one of improved 
design, P/N 1E/N-12-57 (MOD N759), in accordance with the 
ACCOMPLISHMENT INSTRUCTIONS section of Nomad Service Bulletin ANMD-
53-13, Revision 3, dated October 24, 1995.
    (b) 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.
    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, FAA, Los Angeles Aircraft Certification 
Office (ACO), 3960 Paramount Boulevard., Lakewood, California 90712. 
The request shall be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Los Angeles ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

    (d) All persons affected by this directive may obtain copies of 
the document referred to herein upon request to Aerospace 
Technologies of Australia Pty Ltd., ASTA DEFENCE, Private Bag No. 4, 
Beach Road Lara 3212, Victoria, Australia; or may examine this 
document at the FAA, Central Region, Office of the Assistant Chief 
Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.


[[Page 35695]]


    Issued in Kansas City, Missouri, on June 25, 1996.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-17295 Filed 7-5-96; 8:45 am]
BILLING CODE 4910-13-U