[Federal Register Volume 61, Number 235 (Thursday, December 5, 1996)]
[Proposed Rules]
[Pages 64489-64491]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-30798]


      
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 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 61, No. 235 / Thursday, December 5, 1996 / 
Proposed Rules  

[[Page 64489]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-CE-100-AD]
RIN 2120-AA64


Airworthiness Directives; Aerospace Technologies of Australia, 
Nomad N22 and N24 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to supersede AD 85-21-06, which 
currently requires replacing the attachment fittings of the upper fin 
rear spar and the fin/horizontal stabilizer on all Aerospace 
Technologies of Australia (ASTA), Nomad N22 and N24 series airplanes. 
The proposed action would require removing the upper fin to stub fin 
forward attachment bolts, inspecting the attachment fittings for 
cracks, and, if no cracks are found, replacing the attachment bolts 
with bolts of improved design until the life limit of the attachment 
fittings is reached, at which time the attachment fittings would be 
replaced. If cracks are found, the proposed action would require 
replacing the attachment bolts and attachment fittings. Cracks found in 
the underhead radius and at the base of the thread of the bolt prompted 
the proposed AD action. The actions specified by the proposed AD are 
intended to prevent cracking in the upper fin and horizontal stabilizer 
attachment fittings, which if not corrected, could result in loss of 
control of the airplane.

DATES: Comments must be received on or before February 3, 1997.

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-100-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.
    Service information that applies to the proposed AD may be obtained 
from AeroSpace Technologies of Australia, Limited, 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 
above.

FOR FURTHER INFORMATION CONTACT: Mr. Ron Atmur, Aerospace Engineer, Los 
Angeles Aircraft Certification Office, FAA, 3960 Paramount Blvd., 
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-100-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-100-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 exist on ASTA Nomad N22 and N24 series 
airplanes. CASA advises that fatigue cracks have been found in the 
attachment bolt as well as the attachment fitting of the upper fin and 
horizontal stabilizer.
    AD 85-21-06 mandated a life limit of 3,000 total hours time-in-
service to these attachment fittings and at that time the attachment 
fittings should be replaced in accordance with ASTA Service Bulletin 
NMD-53-5, dated October 19, 1984. As a result of cracks being found 
during routine inspections prior to the life limit, ASTA advises that 
the attachment fittings may crack before that time because of increased 
fatigue caused by failure or partial failure of the attachment bolts. 
Therefore, the proposed action would supersede AD 85-21-06 by requiring 
replacement of the old attachment bolt with a bolt of improved design 
to assist in preventing cracks in the attachment fitting before 
reaching the life limit, at which time the attachment fittings would be 
replaced.

Applicable Service Information

    ASTA has issued Nomad Alert Service Bulletin ANMD 55-23, Revision 
1, dated July 11, 1991, which specifies inspecting the attach bolt for 
cracks and replacing the bolt if cracked, and continue to repetitively 
inspect until 3,000 hours time-in-service (TIS). Service Bulletin ANMD 
55-23, Revision 1 then specifies accomplishment of Nomad Service 
Bulletin (SB) NMD-53-5 Rev. 2, dated December 6, 1995, which specifies 
inspecting the attachment bolts and attachment fittings for cracks, and 
replacing the attachment bolts and attachment fittings if cracked, or 
upon the accumulation of 3,000 hours TIS.

FAA's Conclusion

    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

[[Page 64490]]

this bilateral airworthiness agreement, CASA has kept the FAA informed 
of the situation described above. The FAA has examined the findings of 
CASA, 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 the Requirements of the Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop in other ASTA Nomad N22 and N24 series airplanes of 
the same type design registered for operation in the United States, the 
proposed AD would supersede AD 85-21-06 with a new AD that would 
require removing the attachment bolt, part number (P/N) 2/N-00-43, and 
inspecting the attachment fitting for cracks using a dye penetrant 
method. If no cracks are found, the proposed AD would require replacing 
the bolt with a new bolt, P/N 3/N-00-43, and, at the accumulation of 
3,000 total hours time-in-service (TIS), replacing the attachment 
fittings. If cracks are found, the proposed action would require 
replacing the attachment bolts and attachment fittings at the time of 
inspection and prior to further flight.

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 8 
workhours per airplane to accomplish the proposed inspection and bolt 
replacement, and that the average labor rate is approximately $60 an 
hour. Parts cost approximately $236 per airplane. Based on these 
figures, the total cost impact of the proposed AD on U.S. operators is 
estimated to be $10,740 or $716 per airplane. The cost of replacing the 
attachment fittings is not included in these figures because AD 85-21-
06 previously accounted for the cost of the attachment fitting 
replacement.

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 USC 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Airworthiness Directive 
(AD) 85-21-06, Amendment 39-5152, and by adding a new AD to read as 
follows:

Aerospace Technologies of Australia (ASTA): Docket No. 95-CE-100-AD; 
Supersedes AD 85-21-06, Amendment 39-5152.

    Applicability: Nomad N22 and N24 series 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 within the next 100 hours time-in-service 
(TIS) after the effective date of this AD, unless AD 85-21-06 or 
this AD has already been accomplished.
    To prevent cracking in the upper fin and horizontal stabilizer 
attachment fittings, which if not corrected, could result in loss of 
control of the airplane, accomplish the following:
    (a) Remove the attachment bolt (part number (P/N) 2/N-00-43, qty 
2) and inspect the attachment bolt, vertical fin attachment 
fittings, and fin/horizontal stabilizer fittings for cracks, using a 
dye penetrant method, in accordance with the ACCOMPLISHMENT 
INSTRUCTIONS section in Nomad Alert Service Bulletin (ASB) ANMD-55-
23, Revision 1, dated July 11, 1991.
    (1) If no cracks are found, prior to further flight, replace the 
attachment bolts (P/N 2/N-00-43, qty 2) with new attachment bolts 
(P/N 3/N-00-43, qty 2) in accordance with the ACCOMPLISHMENT 
INSTRUCTIONS section in Nomad ASB ANMD-55-23, Revision 1, dated July 
11, 1991.
    (2) If cracks are found, prior to further flight, replace the 
attachment bolts in accordance with the ACCOMPLISHMENT INSTRUCTIONS 
section in Nomad ASB 55-23, Revision 1, dated July 11, 1991, and 
replace the vertical fin attachment fittings and fin/horizontal 
stabilizer fittings in accordance with Nomad Service Bulletin (SB) 
NMD-53-5, Revision 2, dated December 6, 1995.
    (b) Upon the accumulation of 3,000 hours total TIS, unless 
previously accomplished in accordance with paragraph (a)(2) of this 
AD, replace the vertical fin attachment fittings and the fin/
horizontal stabilizer fittings in accordance with the ACCOMPLISHMENT 
INSTRUCTIONS section in Nomad SB NMD-53-5, Revision 2, dated 
December 6, 1995.
    (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 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, 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 
Aircraft Certification Office. Alternative methods of compliance 
approved in accordance with AD 85-21-06 are considered approved as 
alternative methods of compliance for this AD.
    Note 2: 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) All persons affected by this directive may obtain copies of 
the document referred to herein upon request from AeroSpace 
Technologies of Australia, Limited, 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.
    (f) This amendment supersedes AD 85-21-06, Amendment 39-5152.


[[Page 64491]]


    Issued in Kansas City, Missouri, on November 25, 1996.
Henry A. Armstrong,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-30798 Filed 12-4-96; 8:45 am]
BILLING CODE 4910-13-U