```
[Federal Register Volume 62, Number 163 (Friday, August 22, 1997)]
[Rules and Regulations]
[Pages 44535-44537]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-22046]

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-CE-23-AD; Amendment 39-10109; AD 97-17-07]
RIN 2120-AA64

Airworthiness Directives; Aviat Aircraft, Inc. Models S-1S, S-1T, 
S-2, S-2A, S-2S, and S-2B Airplanes (Formerly Known as Pitts Models S-
1S, S-1T, S-2, S-2A, S-2S, and S-2B Airplanes)

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment revises AD 96-12-03, which applies to Aviat 
Aircraft, Inc. (Aviat) Models S-1S, S-1T, S-2, S-2S, and S-2B airplanes 
that are equipped with aft lower fuselage wing attach fittings 
incorporating either part number (P/N) 76090, 2-2107-1, or 1-210-102. 
That AD currently requires repetitively inspecting the aft lower 
fuselage wing attach fitting on both wings for cracks, and modifying 
any cracked aft lower fuselage wing attach fitting. Modifying both aft 
lower fuselage wing attach fittings eliminates the repetitive 
inspection requirement of AD 96-12-03. Aviat recently started 
incorporating modified aft lower fuselage wing attach fittings on newly 
manufactured airplanes. This AD retains the requirements of AD 96-12-
03, but exempts airplanes that had the modified aft lower fuselage wing 
attach fittings incorporated at manufacture. The actions specified by 
this AD are intended to prevent possible in-flight separation of the 
wing from the airplane caused by a cracked fuselage wing attach 
fitting.

DATES: Effective October 3, 1997.
    The incorporation by reference of Aviat Service Bulletin No. 25, 
dated April 3, 1996, Revised November 12, 1996, was approved by the 
Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 
1 CFR part 51 as of October 3, 1997.
    The incorporation by reference of Aviat Service Bulletin No. 25, 
dated April 3, 1996, was previously approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 
as of June 6, 1996 (61 FR 28730).

[[Page 44536]]

ADDRESSES: Service information that applies to this AD may be obtained 
from Aviat Aircraft, Inc., P.O. Box 1240 (postal service delivery), 672 
South Washington Street (express mail), Afton, Wyoming 83110. 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-23-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. Roger Caldwell, Aerospace Engineer, FAA, Denver Aircraft 
Certification Office, 26805 E. 68th Avenue, Room 214, Denver, Colorado 
80249; telephone (303) 342-1086; facsimile (303) 342-1088.
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 Aviat Models S-1S, S-
1T, S-2, S-2A, S-2S, and S-2B airplanes was published in the Federal 
Register as a notice of proposed rulemaking (NPRM) on March 6, 1997 (62 
FR 102360). The NPRM proposed to revise AD 96-12-03 by retaining the 
requirements of that AD for airplanes that do not have aft lower 
fuselage wing attach fittings, either P/N 76090, 2-2107-1, or 1-210-
102, incorporated at manufacture. These aft lower fuselage wing attach 
fittings were incorporated at manufacture on the Model S-2B airplanes 
beginning with serial number 5349. AD 96-12-03 applied to all serial 
numbers of the Model S-2B airplanes. Accomplishment of the proposed AD 
as specified in the NPRM would be in accordance with Aviat SB No. 25, 
dated April 3, 1996, Revised November 12, 1996.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed AD 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 the AD 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 500 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 2 workhours per 
airplane to accomplish the initial inspection, and that the average 
labor rate is approximately $60 an hour. Parts to accomplish the 
inspections cost approximately $100 per airplane. Based on these 
figures, the total cost impact of this AD on U.S. operators is 
estimated to be $110,000. These figures do not take into account the 
cost of repetitive inspections. The FAA has no way of determining how 
many repetitive inspections each owner/operator may incur over the life 
of each airplane.
    In addition, AD 96-12-03 currently requires the same inspections as 
this AD for all 500 of the affected airplanes. The only difference is 
that newly manufactured airplanes are exempt from the actions because 
they have modified aft lower fuselage wing attach fittings incorporated 
at manufacture. Therefore, the cost impact of this AD for operators of 
all affected airplanes is the same as AD 96-12-03.

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 removing Airworthiness Directive 
(AD) 96-12-03, Amendment 39-9645 (61 FR 28730, June 6, 1996), and by 
adding a new AD to read as follows:

97-17-07  Aviat Aircraft, Inc.: Amendment 39-10109; Docket No. 96-
CE-23-AD.

    Applicability: The following airplane models and serial numbers, 
certificated in any category, that are equipped with aft lower 
fuselage wing attach fittings incorporating part number (P/N) 76090, 
2-2107-1, or 1-210-102, and where these aft lower fuselage wing 
attach fittings on both wings have not been modified in accordance 
with the ACCOMPLISHMENT INSTRUCTIONS section of Aviat Service 
Bulletin (SB) No. 25, dated April 3, 1996, Revised November 12, 
1996; or Aviat SB No. 25, dated April 3, 1996:

--Models S-1S, S-1T, S-2, S-2A, and S-2S airplanes, all serial 
numbers.
--Model S-2B airplanes, serial numbers 5000 through 5348.

    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 (e) 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.
    To prevent possible in-flight separation of the wing from the 
airplane caused by a cracked aft lower fuselage wing attach fitting, 
accomplish the following:
    (a) Within the next 50 hours time-in-service (TIS) after the 
effective date of this AD, unless already accomplished (compliance 
with AD 96-12-03), and thereafter at intervals not to exceed 50 
hours TIS, inspect the aft lower fuselage wing attach fitting on 
both wings for cracks. Accomplish these inspections in accordance 
with the ACCOMPLISHMENT INSTRUCTIONS section of Aviat SB No. 25,

[[Page 44537]]

dated April 3, 1996, Revised November 12, 1996; or Aviat SB No. 25, 
dated April 3, 1996.
    (b) If any cracked aft lower fuselage wing attach fitting is 
found during any inspection required by this AD, prior to further 
flight, modify the cracked aft lower fuselage wing attach fitting in 
accordance with the ACCOMPLISHMENT INSTRUCTIONS section of Aviat SB 
No. 25, dated April 3, 1996, Revised November 12, 1996; or Aviat SB 
No. 25, dated April 3, 1996. Repetitive inspections are no longer 
necessary on an aft lower fuselage wing attachment fitting that was 
found cracked and has the referenced modification incorporated.
    (c) Modifying the aft lower fuselage wing attach fitting on both 
wings in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of 
Aviat SB No. 25, dated April 3, 1996, Revised November 12, 1996; or 
Aviat SB No. 25, dated April 3, 1996, is considered terminating 
action for the repetitive inspection requirement of this AD.
    (d) Special flight permits may be issued in accordance with 
Secs. 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.
    (e) 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, Denver Aircraft 
Certification Office, 26805 E. 68th Avenue, Room 214, Denver, 
Colorado 80249. The request shall be forwarded through an 
appropriate FAA Maintenance Inspector, who may add comments and then 
send it to the Manager, Denver ACO. Alternative methods of 
compliance approved in accordance with AD 96-12-03 are considered 
approved 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 Denver ACO.

    (f) The inspections and modification required by this AD shall 
be done in accordance with Aviat Service Bulletin No. 25, dated 
April 3, 1996, Revised November 12, 1996; or Aviat Service Bulletin 
No. 25, dated April 3, 1996.
    (1) The incorporation by reference of Aviat Service Bulletin No. 
25, dated April 3, 1996, Revised November 12, 1996, was approved by 
the Director of the Federal Register in accordance with 5 U.S.C. 
552(a) and 1 CFR part 51.
    (2) The incorporation by reference of Aviat Service Bulletin No. 
25, dated April 3, 1996, was previously approved by the Director of 
the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 
part 51 as of June 6, 1996 (61 FR 28730).
    (3) Copies of these service bulletins may be obtained from Aviat 
Aircraft, Inc., P.O. Box 1240 (postal service delivery), 672 South 
Washington Street (express mail), Afton, Wyoming 83110. 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.
    (g) This amendment (39-10109) revises AD 96-12-03, Amendment 39-
9645.
    (h) This amendment (39-10109) becomes effective on October 3, 
1997.

    Issued in Kansas City, Missouri, on August 13, 1997.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 97-22046 Filed 8-21-97; 8:45 am]
BILLING CODE 4910-13-M
```