AD 96-24-04

[Federal Register Volume 61, Number 227 (Friday, November 22, 1996)]
[Rules and Regulations]
[Pages 59323-59325]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-29723]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-CE-75-AD; Amendment 39-9830; AD 96-24-04]
RIN 2120-AA64


Airworthiness Directives; Aerospace Technologies of Australia, 
Nomad 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 (ASTA) Nomad Models 
N22B, N22S, and N24A airplanes. This action requires repetitively 
inspecting the tailplane stabilizer center section and repairing any 
cracked tailplane structure. This AD also provides an optional 
modification as a terminating action, after an inspection in which no 
cracks are found. A tailplane failure on one of the affected airplanes 
prompted this action. The actions specified by this AD are intended to 
prevent cracking in the stabilizer center section, which, if not 
detected and corrected, could result in tailplane failure and loss of 
control of the airplane.

DATES: Effective January 17, 1997.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 17, 1997.

ADDRESSES: Service information that applies to this AD may be obtained 
from AeroSpace Technologies of Australia, Limited, 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 95-CE-75-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, Los

[[Page 59324]]

Angeles Aircraft Certification Office, FAA, 3960 Paramount Blvd., 
Lakewood, California, 90712; telephone (310) 627-5224; facsimile (310) 
627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an AD that would apply 
to ASTA Nomad Models N22B, N22S, and N24A airplanes was published in 
the Federal Register on March 22, 1996 (61 FR 11784). The action 
proposed to require inspecting (using both visual and eddy current 
methods) the tailplane stabilizer center section for cracks, and prior 
to further flight, repairing any cracked tailplane stabilizer center 
section for these ASTA airplanes that do not have Modifications N663 
and N768 incorporated in the area of the tailplane stabilizer center 
section. This AD also provides the option of modifying the tailplane 
stabilizer center section (Mod. N663 and N768) as a terminating action.

Applicable Service Information

    Accomplishment of the proposed action would be in accordance with 
Nomad Service Bulletin ANMD-55-26, Revision 8, dated April 15, 1994.

Comments

    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.

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 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.

Costs Impact

    The FAA estimates that 15 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 15 workhours per 
airplane to accomplish this action, and that the average labor rate is 
approximately $60 an hour. The total cost impact of this AD upon U.S. 
operators of the affected airplanes is estimated to be $13,500 or $900 
per airplane. This figure only includes the cost for the initial 
inspection and does not include replacement costs if the tailplane 
stabilizer center section is found cracked, nor does it include 
repetitive inspection costs. Additionally, the FAA has no way of 
determining how many tailplane stabilizer center sections may be 
cracked or how many repetitive inspections each owner/operator may 
incur over the life of the airplane.

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:

96-24-04.  Aerospace Technologies of Australia (ASTA): Amendment 39-
9830; Docket No. 95-CE-75-AD.

    Applicability: Nomad Models N22B, N22S, and N24A airplanes (all 
serial numbers), certificated in any category, that have not 
incorporated ASTA Modification N663 and N768 in the area of the 
tailplane stabilizer.

    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 within the next 100 hours time-in-service 
(TIS) after the effective date of this AD, unless already 
accomplished, and thereafter at intervals not to exceed 100 hours 
TIS.
    To prevent cracking in the tailplane stabilizer center section, 
which, if not detected and corrected, could result in tailplane 
failure and loss of control of the airplane, accomplish the 
following:
    (a) Inspect the tailplane stabilizer center section and center 
lightening hole for cracks (using both visual and eddy current 
methods) in accordance with section ``C. Description, (1) Part 1--
Inspection.'' of ASTA Nomad Service Bulletin (SB) ANMD-55-26, 
Revision 8, dated April 15, 1994.
    (b) If cracks are found during any inspection required by this 
AD, prior to further flight, repair the stabilizer center section in 
accordance with a repair scheme obtained from the manufacturer 
through the Manager, Los Angeles Aircraft Certification Office, at 
the address specified in paragraph (d).
    (1) This repair scheme does not eliminate the repetitive 
inspection requirement.
    (2) The repetitive inspection requirement of this AD may be 
terminated by incorporating both Modification (Mod.) N663 and N768 
in accordance with the Accomplishment Instructions section of Nomad 
SB ANMD-55-26, Revision 8, dated April 15, 1994. These modifications 
may only be incorporated, prior to further flight, after any 
inspection, provided no cracks are found.
    (3) Modifications N663 and N768 may also be incorporated as 
terminating action to the repetitive inspections of this AD on 
airplanes that have cracks repaired in the tailplane stabilizer 
center section provided the modifications are incorporated, prior to 
further flight, after an inspection where no cracks were found.

    Note 2: Mod. N663 reworks the horizontal stabilizer to 
incorporate a strengthened main spar assembly that includes a gust 
stop spring box and modified mass balance arm. The trim tab hinges 
are moved 0.17 inches aft and farings are added to the bottom skin 
of the horizontal stabilizer to permit increased trim tab movement. 
Mod. N768 incorporates Mod. N663 and replaces the pivot brackets, 
attachment bolts, and spar web doubler with strengthened components.

    (c) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR

[[Page 59325]]

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 
initial or repetitive compliance times that provides an equivalent 
level of safety may be approved by the Manager, Los Angeles Aircraft 
Certification Office, FAA, 3960 Paramount Blvd., Lakewood, 
California. The request shall be forwarded through an appropriate 
FAA Maintenance Inspector, who may add comments and then send it to 
the Manager, Los Angeles Aircraft Certification Office.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles Aircraft Certification Office.

    (e) The inspections, modifications, and replacements required by 
this AD shall be done in accordance with Nomad Service Bulletin 
ANMD-55-26, Revision 8, dated April 15, 1994. 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, Limited, 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 (39-9830) becomes effective on January 17, 
1997.

    Issued in Kansas City, Missouri, on November 13, 1996.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-29723 Filed 11-21-96; 8:45 am]
BILLING CODE 4910-13-U