[Federal Register Volume 61, Number 110 (Thursday, June 6, 1996)]
[Rules and Regulations]
[Pages 28730-28732]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-14051]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 96-CE-23-AD; Amendment 39-9645; AD 96-12-03]
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; request for comments.
-----------------------------------------------------------------------
SUMMARY: This amendment adopts a new airworthiness directive (AD) that
applies to certain Aviat Aircraft, Inc. (Aviat) Models S-1S, S-1T, S-2,
S-2A, 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. This action 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 the aft lower fuselage wing attach fitting on both
wings eliminates the repetitive inspection requirement of the AD.
Several reports of cracked fuselage wing attach fittings on the
affected airplanes prompted this action. 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 June 24, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of June 24, 1996.
Comments for inclusion in the Rules Docket must be received on or
before August 9, 1996.
ADDRESSES: Submit comments in triplicate to 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.
[[Page 28731]]
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 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, 5440 Roslyn
Street, suite 133, Denver, Colorado 80216; telephone (303) 286-5683;
facsimile (303) 286-5689.
SUPPLEMENTARY INFORMATION:
Events Leading to the AD
The FAA has received 11 reports of the aft lower fuselage wing
attach fittings cracking on Aviat Models S-1S, S-1T, S-2, S-2A, S-2S,
and S-2B airplanes. Five of these incidents were reported on in-service
airplanes and six were found defective during Aviat's in-house
manufacturing process. Each of the cracked aft lower fuselage wing
attach fittings incorporate either part number (P/N) 76090, P/N 2-2107-
1, or P/N 1-210-102. If not detected and corrected, a cracked aft lower
fuselage wing attach fitting could lead to in- flight separation of the
wing from the airplane.
Further analysis of the design of the P/N 76090, 2-2107-1, and 1-
210-102 aft lower fuselage wing attach fittings reveals a bend radius
that could reduce the fatigue life and subsequently make the parts more
susceptible to cracking. Aviat started manufacturing airplanes in 1990
with aft lower fuselage wing attach fittings with a larger bend radius.
The FAA has received no reports of cracking on airplanes incorporating
attach fittings that incorporate this larger bend radius design.
Aviat has issued Service Bulletin (SB) No. 25, dated April 3, 1996,
which specifies procedures for inspecting and modifying the aft lower
fuselage wing attach fittings incorporating either P/N 76090, 2-2107-1,
and 1-210-102.
After examining the circumstances and reviewing all available
information related to the incidents described above, the FAA has
determined that AD action should be taken to prevent possible in-flight
separation of the wing from the airplane caused by a cracked fuselage
wing fitting.
Explanation of the Provisions of the AD
Since an unsafe condition has been identified that is likely to
exist or develop in other Aviat Models S-1S, S-1T, S-2, S-2A, S-2S, and
S-2B airplanes of the same type design that are equipped with aft lower
fuselage wing attach fittings incorporating either P/N 76090, 2-2107-1,
or 1-210-102, this AD 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 the aft
lower fuselage wing fitting on both wings eliminates the repetitive
inspection requirement of this AD. Accomplishment of the required
actions is in accordance with Aviat SB No. 25, dated April 3, 1996.
Since a situation exists (possible in-flight separation of the wing
from the airplane) that requires the immediate adoption of this
regulation, it is found that notice and opportunity for public prior
comment hereon are impracticable, and that good cause exists for making
this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting immediate flight safety and, thus, was not
preceded by notice and opportunity to comment, comments are invited on
this rule. Interested persons are invited to comment on this 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 will be considered,
and this rule may be amended in light of the comments received. Factual
information that supports the commenter's ideas and suggestions is
extremely helpful in evaluating the effectiveness of the AD action and
determining whether additional rulemaking action would be needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the 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
AD 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. 96-CE-23-AD.'' The postcard will be date stamped and
returned to the commenter.
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.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and is not a significant regulatory action under
Executive Order 12866. It has been determined further that this action
involves an emergency regulation under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979). If it is determined that
this emergency regulation otherwise would be significant under DOT
Regulatory Policies and Procedures, a final regulatory evaluation will
be prepared and placed in the Rules Docket (otherwise, an evaluation is
not required). A copy of it, if filed, may be obtained from the Rules
Docket.
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:
96-12-03 Aviat Aircraft, Inc.: Amendment 39-9645; Docket No. 96-
CE-23-AD.
Applicability: Models S-1S, S-1T, S-2, S-2A, S-2S, and S-2B
airplanes (formerly
[[Page 28732]]
known as Pitts Models S-1S, S-1T, S-2, S-2A, S-2S, and S-2B
airplanes), all 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.
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 initially within the next 50 hours
time-in-service (TIS) after the effective date of this AD, unless
already accomplished, and thereafter at intervals not to exceed 50
hours TIS.
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) Inspect the aft lower fuselage wing attach fitting on both
wings for cracks in accordance with the ACCOMPLISHMENT INSTRUCTIONS
section of Aviat Service Bulletin (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. Repetitive inspections are no longer
necessary on a cracked aft lower fuselage wing attachment fitting
that 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, is considered terminating
action for the repetitive inspection requirement of this AD.
(d) 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.
(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, 5440 Roslyn Street, suite 133, Denver,
Colorado 80216. The request shall be forwarded through an
appropriate FAA Maintenance Inspector, who may add comments and then
send it to the Manager, Denver ACO.
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 inspection and modification (if necessary) required by
this AD shall be done in accordance with Aviat Service Bulletin No.
25, dated April 3, 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 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 (39-9645) becomes effective on June 24, 1996.
Issued in Kansas City, Missouri, on May 29, 1996.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 96-14051 Filed 6-5-96; 8:45 am]
BILLING CODE 4910-13-U