[Federal Register Volume 60, Number 35 (Wednesday, February 22, 1995)]
[Proposed Rules]
[Pages 9799-9800]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-4251]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 93-CE-61-AD]
Airworthiness Directives; Piper Aircraft Corporation PA24, PA28R,
PA30, PA32R, PA32RT, PA34-200, PA34-200T, PA39, and PA44 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes to adopt a new airworthiness directive
(AD) that would apply to certain Piper Aircraft Corporation (Piper)
PA24, PA28R, PA30, PA32R, PA32RT, PA34-200, PA34-200T, PA39, and PA44
series airplanes. The proposed action would require repetitively
inspecting the main gear side brace studs for cracks and replacing any
cracked main gear side brace stud. Several reports of main gear side
brace stud cracks on the affected airplanes, including seven incidents
where the main landing gear (MLG) collapsed, prompted the proposed AD.
The actions specified by the proposed AD are intended to prevent a MLG
collapse caused by main gear side brace stud cracks, which, if not
detected and corrected, could result in loss of control of the airplane
during landing operations.
DATES: Comments must be received on or before May 5, 1995.
ADDRESSES: Submit comments in triplicate to the FAA, Central Region,
Office of the Assistant Chief Counsel, Attention: Rules Docket No. 93-
CE-61-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.
Information that relates to the proposed AD may be inspected at the
Rules Docket at the address above.
FOR FURTHER INFORMATION CONTACT: Christina Marsh, Aerospace Engineer,
FAA, Atlanta Aircraft Certification Office, Campus Building, 1701
Columbia Avenue, Suite 2-160, College Park, Georgia 30337-2748;
telephone (404) 305-7362; facsimile (404) 305-7348.
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. 93-CE-61-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. 93-CE-61-AD, Room 1558, 601 E. 12th Street,
Kansas City, Missouri 64106.
Discussion
The FAA has received several reports of main gear side brace stud
cracks on Piper PA24, PA32R, PA34-200, and PA34-200T series airplanes.
These reports include an accident in the United Kingdom where the main
landing gear (MLG) collapsed on a Piper PA34-200 series airplane
because of high cycle fatigue cracking of the main gear side brace
stud. Metallurgical examination of the stud revealed that separate
fatigue cracks had originated from both the inboard and the outboard
edges near the bending radius of the shank. Reverse bending loads then
allowed these cracks to extend across approximately 30-percent of the
shank cross-section. The remaining 70-percent of the shank cross-
section failed because of overstress. Review of service difficulty
records in the United Kingdom and Canada, as well as the United States,
indicated that this accident was almost identical to other accidents on
Piper airplane models of similar type design.
On February 11, 1994, the FAA issued an advance notice of proposed
rulemaking (ANPRM) to solicit comments from owners/operators of the
affected airplanes in order to adequately make a determination as to
what type of action to take (if any). From responses to this ANPRM, the
FAA found that most of the owners/operators that responded are
currently inspecting the main gear side brace studs on a routine basis
(every annual or 100 hours); however, these operators are not removing
the studs or using non-destructive inspection methods. Based on its
review of the above-referenced incidents, the FAA has determined that,
in order to adequately detect any cracks on the main gear side brace
studs, these studs must be removed and inspected using dye penetrant or
magnetic particle methods.
After examining the circumstances and reviewing all available
information related to the incidents and accidents described above,
including the comments received in response to the ANPRM, the FAA has
determined that AD action should be taken to prevent MLG collapse
caused by main gear side brace stud cracks, which, if not detected and
corrected, could result in loss of control of the airplane during
landing operations.
Since an unsafe condition has been identified that is likely to
exist or develop in other Piper PA24, PA28R, PA30, PA32R, PA32RT, PA34-
200, PA34-200T, PA39, and PA44 series airplanes of the same type
design, the proposed AD would require repetitively inspecting (using
dye penetrant or magnetic particle methods) the main gear side brace
studs for cracks, and replacing any cracked main gear side brace stud.
The FAA estimates that 9,200 airplanes in the U.S. registry would
be affected by the proposed AD, that it would take approximately 5
workhours to initially inspect both the right and left main landing
gear side brace studs, and that the average labor rate is approximately
$60 an hour. Based on these figures, the total cost impact of the
proposed AD on U.S. operators is estimated to be $2,760,000. This
figure represents the cost of the initial inspection, and does not
reflect costs for [[Page 9800]] repetitive inspections or possible
replacements. The FAA has no way of determining how many main gear side
brace studs may need replacement or how many repetitive inspections
each owner/operator may incur.
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.
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 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding a new AD to read as follows:
Piper Aircraft Corporation: Docket No. 93-CE-61-AD. Applicability:
PA24, PA28R, PA30, PA32R, PA32RT, PA34-200, PA34-200T, PA39, and
PA44 series airplanes (all models and serial numbers), certificated
in any category. Compliance: Required within the next 100 hours
time-in-service (TIS) after the effective date of this AD, unless
already accomplished, and thereafter as indicated.
To prevent main landing gear (MLG) collapse caused by main gear
side brace stud cracks, which, if not detected and corrected, could
result in loss of control of the airplane during landing operations,
accomplish the following:
(a) Remove both the left and right main gear side brace studs
from the airplane in accordance with the instructions contained in
the Landing Gear section of the maintenance manual, and inspect each
main gear side brace stud for cracks, using FAA-approved dye
penetrant or magnetic particle methods.
(1) For any main gear side brace stud found cracked, prior to
further flight, replace the cracked stud with an FAA-approved
serviceable part (part numbers referenced in the table in paragraph
(b) of this AD) in accordance with the instructions contained in the
Landing Gear section of the applicable maintenance manual, and
reinspect as specified in paragraph (b) of this AD.
(2) For any main gear side brace stud not found cracked, prior
to further flight, reinstall the uncracked stud in accordance with
the instructions contained in the Landing Gear section of the
applicable maintenance manual, and reinspect as specified in
paragraph (b) of this AD.
(b) Reinspect both the left and right main gear side brace
studs, using FAA-approved dye penetrant or magnetic particle
procedures, at the applicable intervals presented below, and replace
any cracked stud or reinstall any uncracked stud as specified in
paragraphs (a)(1) and (a)(2) of this AD, respectively:
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Series Airplanes
Part number installed TIS inspection interval Installed on
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20829-00............... 1,000 hours............ PA24.
22512-00............... 1,000 hours............ PA24, PA30, and PA39
95299-0 500 hours.............. PA28R, PA32R, PA32RT,
0 or PA34-200, PA34-200T,
95299- and PA44.
02.
78717-02 (contained in 1,000 hours............ PA28R, PA32R, PA32T,
the part number 95643- PA34-200, PA34-200T,
06 or 95643-07 bracket and PA44.
assembly).
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Note 1: Main gear side brace studs, part numbers, 95299-00 and
95299-02, are no longer manufactured, and any main gear side brace
stud found cracked incorporating one of these part numbers may be
replaced with a part number 78717-02 main gear side brace stud
contained in the part number 95643-06 and 95643-07 bracket assembly.
Note 2: Accomplishing the actions of this AD does not affect the
requirements of AD 77-13-21, Amendment 39-3093. The tolerance
inspection requirements of that AD still apply for Piper PA24, PA30,
and PA39 series airplanes.
(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, Atlanta Aircraft
Certification Office (ACO), Campus Building, 1701 Columbia Avenue,
Suite 2-160, College Park, Georgia 30337-2748. The request shall be
forwarded through an appropriate FAA Maintenance Inspector, who may
add comments and then send it to the Manager, Atlanta ACO.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Atlanta ACO.
(e) Information related to this AD may be inspected at the FAA,
Central Region, Office of the Assistant Chief Counsel, Room 1558,
601 E. 12th Street, Kansas City, Missouri.
Issued in Kansas City, Missouri, on February 14, 1995.
Barry D. Clements,
Manager, Small Airpane Directorate, Aircraft Certification Service.
[FR Doc. 95-4251 Filed 2-21-95; 8:45 am]
BILLING CODE 4910-13-U