[Federal Register Volume 61, Number 96 (Thursday, May 16, 1996)]
[Rules and Regulations]
[Pages 24684-24686]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-12137]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-CE-20-AD; Amendment 39-9619; AD 96-10-12]
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.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
applies to Aviat Aircraft, Inc. (Aviat) Models S-1S, S-1T, S-2, S-2A,
S-2S, and S-2B airplanes that are equipped with a flight control stick
with a wall thickness of .035 inch. This action requires repetitively
inspecting the flight control stick for cracks, and replacing any
cracked flight control stick with one with a wall thickness of .058
inch. An incident on an Aviat Model S-2A airplane where the flight
control stick fractured in flight prompted this action. The actions
specified by this AD are intended to prevent the inability to maneuver
the airplane because of a cracked flight control stick, which, if not
detected and corrected, could result in loss of control of the
airplane.
DATES: Effective June 7, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of June 7, 1996.
Comments for inclusion in the Rules Docket must be received on or
before July 19, 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-20-AD, Room 1558, 601 E. 12th
Street, Kansas City, Missouri 64106.
Service information that applies to this AD may be obtained from
Aviat Aircraft, Inc., The Airport-Box 1240, South Washington Street,
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-20-AD, Room
1558, 601 E. 12th Street, Kansas City, Missouri 64106; or
[[Page 24685]]
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 This Action
The FAA has received a report of the flight control stick
fracturing in flight on an Aviat Model S-2A airplane. Analysis of the
fractured flight control stick revealed fatigue cracking at the upper
weld above the pivot bearing. The flight control stick in the
referenced incident had a wall thickness of .035-inch. If not detected
and corrected, a cracked flight control stick could result in the
inability to maneuver the airplane with subsequent loss of control of
the airplane.
Aviat has issued Service Bulletin (SB) No. 23, dated March 29,
1996, which specifies procedures for (1) Inspecting, using dye
penetrant methods, the .035-inch wall thickness flight control stick;
and (2) installing a flight control stick with a wall thickness of .058
inch.
The affected airplane had accumulated 2,015 hours time-in-service
(TIS) when the incident occurred. The FAA has determined that cracking
in this area can develop after 1,000 hours TIS accumulated on a .035-
inch wall thickness flight control stick. All Model S-2A airplanes and
some Model S-2S airplanes were equipped with a .035-inch wall thickness
flight control stick at manufacture. Models S-1S, S-1T, S-2, S-2B and
certain Model S-2S airplanes were manufactured with control sticks with
a wall thickness greater than .035 inch, but could have .035-inch
flight control sticks installed through FAA-approved field
modification.
After examining the circumstances and reviewing all available
information related to the incident described above, the FAA has
determined that (1) flight control sticks with a wall thickness of .035
inch should be repetitively inspected for cracking after 1,000 hours
TIS; and (2) AD action should be taken to prevent the inability to
maneuver the airplane because of a cracked flight control stick, which,
if not detected and corrected, could result in loss of control of the
airplane.
Explanation of the Provisions of the AD
Since an unsafe condition has been identified that is likely to
exist or develop in other Aviat S-1S, S-1T, S-2, S-2A, S-2S, and S-2B
airplanes of the same type design that are equipped with a .035-inch
wall thickness flight control stick, this AD requires repetitively
inspecting the affected flight control stick for cracks, and replacing
any cracked flight control stick with one with a wall thickness of .058
inch. This action also allows the option of installing a .058-inch wall
thickness flight control stick as terminating action for the repetitive
inspection requirement if cracks were not found. Accomplishment of the
required actions are in accordance with Aviat SB No. 23, dated March
29, 1996.
Since a situation exists (possible inability to maneuver the
airplane with subsequent loss of control of 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-20-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:
96-10-12 Aviat Aircraft, Inc.: Amendment 39-9619; Docket No. 96-CE-
20-AD.
Applicability: 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), all serial numbers, certificated in any
category, that are
[[Page 24686]]
equipped with a flight control stick with a wall thickness of .035
inch.
Note 1: All Model S-2A airplanes and some Model S-2S airplanes
were equipped with a .035-inch wall thickness flight control stick
at manufacture. Models S-1S, S-1T, S-2, S-2B and certain Model S-2S
airplanes were manufactured with control sticks with a wall
thickness greater than .035 inch, but could have .035-inch flight
control sticks installed through FAA-approved field modification.
Note 2: 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 initially upon accumulating 1,000 hours
time-in-service (TIS) or within the next 25 hours TIS after the
effective date of this AD, whichever occurs later, unless already
accomplished, and thereafter as indicated in the body of this AD.
To prevent the inability to maneuver the airplane because of a
cracked control stick, which, if not detected and corrected, could
result in loss of control of the airplane, accomplish the following:
(a) Inspect, using dye penetrant methods, the .035-inch wall
thickness flight control stick for cracking in accordance with the
ACCOMPLISHMENT INSTRUCTIONS section of Aviat Service Bulletin (SB)
No. 23, dated March 29, 1996.
Note 3: Aviat SB No. 23, dated March 29, 1996, only references
the Model S-2A airplanes. The procedures included in this service
bulletin should be utilized for all of the airplanes affected by
this AD.
(1) If cracking is found, prior to further flight, replace the
.035-inch wall thickness flight control stick with one with a .058
inch wall thickness in accordance with the ACCOMPLISHMENT
INSTRUCTIONS section of Aviat SB No. 23, dated March 29, 1996.
(2) If no cracks are found, reinspect at intervals not to exceed
50 hours TIS. If cracking is found during any repetitive inspection,
prior to further flight, accomplish the replacement specified in
paragraph (a)(1) of this AD.
(b) Replacing the .035-inch wall thickness flight control stick
with one with a .058-inch wall thickness in accordance with the
ACCOMPLISHMENT INSTRUCTIONS section of Aviat SB No. 23, dated March
29, 1996, is considered terminating action for the repetitive
inspection requirement of this AD. This replacement may be
accomplished at any time, and must be accomplished prior to further
flight if cracking is found as required by paragraph (a)(1) 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
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 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Denver ACO.
(e) The inspection and replacement (if necessary) required by
this AD shall be done in accordance with Aviat Service Bulletin No.
23, dated March 29, 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., The Airport-Box 1240, South Washington Street,
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.
(f) This amendment (39-9619) becomes effective on June 7, 1996.
Issued in Kansas City, Missouri, on May 8, 1996.
Henry A. Armstrong,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-12137 Filed 5-15-96; 8:45 am]
BILLING CODE 4910-13-U
