[Federal Register Volume 62, Number 103 (Thursday, May 29, 1997)]
[Rules and Regulations]
[Pages 29001-29002]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-14075]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-CE-57-AD; Amendment 39-10040; AD 97-11-11]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to Aerospace Technologies of Australia Pty Ltd. (ASTA) Models 
N22B, N22S, and N24A airplanes. This action requires repetitively 
inspecting the horizontal stabilizer upper and lower skin, intercostal 
angles, and the horizontal stabilizer trailing edge channel for cracks; 
and repairing any crack or replacing any cracked parts, as applicable. 
This AD results from numerous reports of cracking in these horizontal 
stabilizer areas on the affected airplanes. The actions specified by 
this AD are intended to prevent structural failure of the horizontal 
stabilizer caused by fatigue cracks, which could result in loss of 
control of the airplane.

DATES: Effective July 11, 1997.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of July 11, 1997.

ADDRESSES: Service information that applies to this 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 may also be examined at the Federal Aviation Administration 
(FAA), Central Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket 96-CE-57-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106; or at the Office of the Federal Register, 
800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. Ron Atmur, Aerospace Engineer, 
FAA, Los Angeles Aircraft Certification Office, 3960 Paramount 
Boulevard, Lakewood, California 90712; telephone (562) 627-5224; 
facsimile (562) 627-5210.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to ASTA Models N22B, 
N22S, and N24A airplanes was published in the Federal Register as a 
notice of proposed rulemaking (NPRM) on December 10, 1996 (61 FR 
65004). The NPRM proposed to require repetitively inspecting the 
horizontal stabilizer upper and lower skin, intercostal angles, and the 
horizontal stabilizer trailing edge channel for cracks; and repairing 
any crack or replacing any cracked parts, as applicable. Accomplishment 
of the proposed inspections as specified in the NPRM would be in 
accordance with Nomad Service Bulletin NMD-55-34, dated April 22, 1996. 
Accomplishment of any proposed repair or replacement (as necessary and 
as applicable) as specified in the NPRM would be in accordance with the 
Nomad Structural Repair Manual, Chapter 55-10-11.
    The NPRM resulted from numerous reports of cracking in these 
horizontal stabilizer areas on the affected airplanes.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of

[[Page 29002]]

the rule as proposed except for minor editorial corrections. The FAA 
has determined that these minor corrections will not change the meaning 
of the AD and will not add any additional burden upon the public than 
was already proposed.

Cost Impact

    The FAA estimates that 15 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 2 workhours per 
airplane to accomplish the required action, and that the average labor 
rate is approximately $60 an hour. Based on these figures, the total 
cost impact of the AD on U.S. operators is estimated to be $1,800 or 
$120 per airplane. This figure does not take into account the cost of 
repetitive inspections or the cost to repair or replace any horizontal 
stabilizer upper and lower skin, intercostal angles, or horizontal 
stabilizer trailing edge channel. The FAA has no way of determining the 
number of repetitive inspections each operator will incur over the life 
of each affected airplane or the number of horizontal stabilizer upper 
and lower skins, intercostal angles, or horizontal stabilizer trailing 
edge channels that may be found cracked during the inspections required 
by this action.

Regulatory Impact

    The regulations adopted herein will 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 final 
rule does 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) 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 final 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, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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 a new airworthiness directive 
(AD) to read as follows:

97-11-11  Aerospace Technologies of Australia PTY LTD: Amendment 39-
10040; Docket No. 96-CE-57-AD.

    Applicability: Models N22B, N22S, and N24A airplanes (all serial 
numbers), 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 in the body of this AD, unless 
already accomplished.
    To prevent structural failure of the horizontal stabilizer 
caused by fatigue cracks, which could result in loss of control of 
the airplane, accomplish the following:
    (a) Within the next 100 hours time-in-service (TIS) after the 
effective date of the AD, and thereafter at intervals not to exceed 
100 hours TIS, inspect the horizontal stabilizer upper and lower 
skin, intercostal angles, and the horizontal stabilizer trailing 
edge channel for cracks in accordance with the Accomplishment 
instructions section of Nomad Service Bulletin (SB) NMD-55-34, dated 
April 22, 1996.
    (b) If any crack is found during any inspection required by this 
AD, prior to further flight, repair or replace the cracked part or 
area, as applicable, in accordance with the Nomad Structural Repair 
Manual, Chapter 55-10-11. Those cracked areas that can be repaired 
and those cracked areas that must be replaced are defined in Nomad 
SB NMD-55-34, dated April 22, 1996, and the Nomad Structural Repair 
Manual, Chapter 55-10-11. Repairing a crack or replacing a cracked 
part does not eliminate the repetitive inspection requirement of 
this AD.
    (c) 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.
    (d) 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 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.

    (e) The inspections required by this AD shall be done in 
accordance with Nomad Service Bulletin NMD-55-34, dated April 22, 
1996. This incorporation by reference was approved by the Director 
of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 
part 51. Copies may be obtained from Aerospace Technologies of 
Australia Pty Ltd., ASTA Defence, Private Bag No. 4, Beach Road Lara 
3212, Victoria, Australia. Copies may be inspected at the FAA, 
Central Region, Office of the Assistant Chief Counsel, Room 1558, 
601 E. 12th Street, Kansas City, Missouri, or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.
    (f) This amendment (39-10040) becomes effective on July 11, 
1997.

    Issued in Kansas City, Missouri, on May 22, 1997.
Henry A. Armstrong,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-14075 Filed 5-28-97; 8:45 am]
BILLING CODE 4910-13-U