[Federal Register Volume 61, Number 81 (Thursday, April 25, 1996)]
[Proposed Rules]
[Pages 18299-18303]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-10167]



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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-CE-09-AD]
RIN 2120-AA64


Airworthiness Directives; The New Piper Aircraft, Inc. PA24, 
PA28R, PA30, PA32R, PA34, and PA39 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: This document proposes to supersede AD 95-20-07, which 
currently requires repetitively inspecting the main gear side brace 
studs for cracks on certain The New Piper Aircraft, Inc. (Piper) PA24, 
PA28R, PA30, PA32R, PA34, and PA39 series airplanes, and replacing any 
cracked main gear side brace stud. The proposed action would retain the 
repetitive inspection and possible replacement requirements of AD 95-
20-07, would remove airplanes with a certain main gear side brace 
assembly configuration from the ``Applicability'' section of the 
current AD, and would incorporate additional modification and 
replacement options. Additional information on the design and service 
history of the affected airplanes concerning this subject received by 
the Federal Aviation Administration (FAA) after issuance of AD 95-20-07 
prompted the proposed action. The actions specified by the proposed AD 
are intended to prevent a main landing gear 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 June 25, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 96-CE-09-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 applies to the proposed AD may be examined 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. 96-CE-09-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. 96-CE-09-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Discussion

    AD 95-20-07, Amendment 39-9386 (60 FR 52073, October 5, 1995), 
currently requires repetitively inspecting (using liquid penetrant or 
magnetic particle methods) the main gear side brace studs for cracks on 
certain Piper PA24, PA28R, PA30, PA32R, PA34, and PA39 series 
airplanes, and replacing any cracked main gear side brace stud. A minor 
correction on this action that specified who could accomplish the 
inspection was published in the Federal Register on November 15, 1995 
(60 FR 57333).
    The FAA has re-examined all available information related to AD 95-
20-07, including additional information received from The New Piper 
Aircraft, Inc., and owners/operators of the affected airplanes. From 
this examination, the FAA has determined the following:

--That a third main gear side brace assembly containing the \5/8\-inch 
stud, part number (P/N) 78717-02, with a two-piece bushing, P/N 67026-
09, was installed (at manufacture) on Piper Model PA34-200T, serial 
numbers 34-7670325 through 34-7770372. AD 95-20-07 should not apply to 
these airplanes with this main gear side brace assembly configuration; 
and
--That Piper PA28R, PA32R, and PA34 series airplane owners/operators 
should have the option of incorporating a modification that would 
eliminate the repetitive inspection requirement of AD 95-20-07. This 
modification consists of reaming the existing two-piece bushings, P/N 
67026-6, to an inside diameter of .624-inch to .625-inch, rechamfering 
the bushings, and installing the \5/8\-inch stud, P/N 78717-02. The 
owner/operator would have the choice of incorporating this 
modification, installing a P/N 95643-06/-07/-08/-09 main gear side 
brace bracket assembly, or continuing to reinspect the main gear side 
brace assembly.

    Based upon the information described above, the FAA has determined 
that AD action should be taken to prevent a main landing gear 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

[[Page 18300]]

develop in other Piper PA24, PA28R, PA30, PA32R, PA34, and PA39 series 
airplanes of the same type design, the proposed AD would supersede AD 
95-20-07 with a new AD that would (1) retain the requirement of 
repetitively inspecting the main gear side brace assembly, and 
replacing any cracked main gear side brace stud. This includes the 
inspection-terminating replacement contained in AD 95-20-07; (2) remove 
from the ``Applicability'' section of the current AD the Piper Model 
PA34-200T airplanes that incorporate a main gear side brace assembly 
containing the \5/8\-inch stud, part number (P/N) 78717-02, with a two-
piece bushing, P/N 67026-09; and (3) incorporate, as an option, an 
inspection-terminating modification for Piper PA28R, PA32R, and PA34 
airplanes. This modification consists of reaming the existing two-piece 
bushings, P/N 67026-6, to an inside diameter of .624-inch to .625-inch, 
rechamfering the bushings, and installing the \5/8\-inch stud, P/N 
78717-02.
    The FAA estimates that 13,200 airplanes in the U.S. registry would 
be affected by the proposed AD, that it would take approximately 5 
workhours per airplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Based on these 
figures, the total cost impact of the proposed inspection on U.S. 
operators is estimated to be $3,960,000. This figure represents the 
total cost of the proposed initial inspection, and does not reflect 
costs for any of the proposed 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 over the life of the airplane.
    In addition, the proposed AD would require the same inspections 
required by AD 95-20-07. The only difference between the proposed AD 
and AD 95-20-07 is the addition of an inspection-terminating 
modification option and the elimination from the ``Applicability'' 
section certain airplanes that incorporate a certain main side brace 
stud assembly. The proposed AD would not provide any additional cost 
impacts over that already required by AD 95-20-07.
    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 14 
CFR part 39 of the Federal Aviation Regulations 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) 95-20-07, Amendment 39-9386, and by adding a new AD to read as 
follows:

The New Piper Aircraft, Inc.: Docket No. 96-CE-09-AD; Supersedes AD 
95-20-07, Amendment 39-9386.

    Applicability: The following airplane models and serial numbers, 
certificated in any category:
    1. All serial numbers of Models PA24, PA24-250, PA24-260, PA24-
400, PA30, and PA39 airplanes;
    2. The following model and serial number airplanes that are not 
equipped with a part number (P/N) 78717-02 main landing gear side 
brace stud in both right and left main landing gear sidebrace 
bracket assemblies:

------------------------------------------------------------------------
              Model                              Serial No.             
------------------------------------------------------------------------
PA28R-180                          28R-30002 through 28R-31135, and 28R-
                                    7130001 through 28R-7130013.        
PA28R-200                          28R-35001 through 28R-35820, and 28R-
                                    7135001 through 28R-7635539.        
PA28R-201                          28R-7737002 through 28R-7737096.     
PA28R-201T                         28R-7703001 through 28R-7703239.     
PA32R-300                          32R-7680001 through 32R-7780444.     
PA34-200                           All serial numbers.                  
PA34-200T                          34-7570001 through 34-7770372.       
------------------------------------------------------------------------

    Note 1: P/N 78717-02 side brace stud was installed at 
manufacture on Piper Model PA34-200T airplanes, serial numbers 34-
7670325 through 34-7770372.
    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 (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 as follows, and thereafter as 
specified in the body of this AD:
    1. For the affected Models PA28R-180, PA28R-200, PA28R-201, 
PA28R-201T, PA32R-300, PA34-200, and PA34-200T airplanes: Within the 
next 100 hours time-in-service (TIS) after the effective date of 
this AD or, if the main gear side brace stud has already been 
inspected or replaced as specified in this AD, within 500 hours TIS 
after the last inspection or replacement, whichever occurs later.
    2. For the affected Models PA24, PA24-250, PA24-260, PA24-400, 
PA30, and PA39 airplanes: Within the next 100 hours time-in-service 
(TIS) after the effective date of this AD or, if the main gear side 
brace stud has already been inspected or replaced as specified in 
this AD, within 1,000 hours TIS after the last inspection or 
replacement, whichever occurs later.
    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:

    Note 3: The paragraph structure of this AD is as follows:

Level 1: (a), (b), (c), etc.
Level 2: (1), (2), (3), etc.
Level 3: (i), (ii), (iii), etc.

Level 2 and Level 3 structures are designations of the Level 1 
paragraph they immediately follow.
    (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 Type I (fluorescent) 
liquid penetrant or magnetic particle inspection methods. Figure 1 
of this

[[Page 18301]]

AD depicts the area of the sidebrace stud shank where the sidebrace 
stud is to be inspected.

    Note 4: All affected Models PA24 and PA24-250 airplanes were 
equipped at manufacture with P/N 20829-00 main gear side brace 
studs. All affected Models PA24-260, PA24-400, PA30, and PA39 
airplanes were equipped at manufacture with P/N 22512-00 main gear 
side brace studs. The Appendix included with this AD contains 
information on determining the P/N of the bracket assembly on the 
affected PA28R, PA32R, and PA34 series airplanes.

BILLING CODE 4910-13-U
      

[[Page 18302]]

[GRAPHIC] [TIFF OMITTED] TP25AP96.004



BILLING CODE 4910-13-C

[[Page 18303]]

    (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 or FAA-approved equivalent) in accordance with the 
instructions contained in the Landing Gear section of the applicable 
maintenance manual, and accomplish one of the following, as 
applicable:
    (i) Reinspect and replace (as necessary) as specified in 
paragraph (b) of this AD; or
    (ii) For the affected Models PA28R-180, PA28R-200, PA28R-201, 
PA28R-201T, PA32R-300, PA34-200, and PA34-200T airplanes, the P/N 
95299-00 or 95299-02 main gear side brace studs are no longer 
manufactured. Install a new main gear side brace stud bracket 
assembly, P/N 95643-06, P/N 95643-07, P/N 95643-08, or P/N 95643-09, 
as applicable. No repetitive inspections will be required by this AD 
for these affected airplane models when this bracket assembly is 
installed; or
    (iii) For the affected Models PA28R-180, PA28R-200, PA28R-201, 
PA28R-201T, PA32R-300, PA34-200, and PA34-200T airplanes, ream the 
existing two-piece bushings, P/N 67026-6, to an inside diameter of 
.624-inch to .625-inch, rechamfer the bushings, and install the \5/
8\-inch stud, P/N 78717-02. No repetitive inspections will be 
required by this AD when this action is accomplished. If the 
bushings cannot be reamed while installed in the bracket (i.e., the 
brackets are loose), then install a main gear side brace bracket 
assembly, P/N 95643-06, P/N 95643-07, P/N 95643-08, or P/N 95643-09, 
as applicable. No repetitive inspections will be required by this AD 
when this bracket assembly is installed.
    (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 and replace (as 
necessary) as specified in paragraph (b) of this AD.
    (b) Reinspect both the left and right main gear side brace 
studs, using Type I (fluorescent) liquid penetrant or magnetic 
particle inspection methods. Replace any cracked stud or reinstall 
any uncracked stud as specified in paragraphs (a)(1) and (a)(2) of 
this AD, respectively:

------------------------------------------------------------------------
                              TIS inspection                            
     Part No. installed          interval      Model airplanes installed
                                  (hours)                 on            
------------------------------------------------------------------------
20829-00....................           1,000  PA24 and PA24-250.        
22512-00....................           1,000  PA24-260, PA24-400, PA30, 
                                               and PA39.                
95299-00 or 95299-02........             500  PA28R-180, PA28R-200,     
                                               PA28R-201, PA28R-201T,   
                                               PA32R-300, PA34-200, and 
                                               PA34-200T.               
------------------------------------------------------------------------

    Note 5: 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) Owners/operators of the affected Models PA28R-180, PA28R-
200, PA28R-201, PA28R-201T, PA32R-300, PA34-200, and PA34-200T 
airplanes may accomplish one of the following at any time to 
terminate the repetitive inspection requirement of this AD:
    (1) Install a main gear side brace bracket assembly, P/N 95643-
06, P/N 95643-07, P/N 95643-08, or P/N 95643-09, as applicable, 
which contains the \5/8\-inch diameter main gear side brace stud, P/
N 78717-02, and the one-piece bushing, P/N 67026-12; or
    (2) Ream the existing two-piece bushings, P/N 67026-6, to an 
inside diameter of .624-inch to .625-inch, rechamfer the bushings, 
and install the \5/8\-inch stud, P/N 78717-02. If the bushings 
cannot be reamed while installed in the bracket (i.e., the brackets 
are loose), then install a main gear side brace bracket assembly, P/
N 95643-06, P/N 95643-07, P/N 95643-08, or P/N 95643-09, as 
applicable.
    (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, 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 6: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Atlanta ACO.

    (f) Alternative methods of compliance approved in accordance 
with AD 95-20-07, Amendment 39-9386, are considered approved as 
alternative methods of compliance with this AD.
    (g) 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.
    (h) This amendment supersedes AD 95-20-07, Amendment 39-9386.

Appendix to Docket No. 96-CE-09-AD--Information To Determine Main Gear 
Side Brace Stud Assembly Part Number (P/N)

--The P/N 95643-00/-01/-02/-03 bracket assembly contains the 9/16-
inch diameter main gear side brace stud, P/N 95299-00/-02, and a 
two-piece bushing, P/N 67026-6.
--The P/N 95643-06/-07/-08/-09 bracket assembly contains the 5/8-
inch diameter main gear side brace stud, P/N 78717-02, and a one-
piece bushing, P/N 67026-12.
--Both the one-piece and the two-piece bushing have a visible 
portion of the bushing flange, i.e., bushing shoulder.
--Whether a one-piece or two-piece bushing is installed may be 
determined by measuring the outside diameter of the bushing flange 
with a micrometer (jaws of the caliper must be 3/32-inch or less). 
The two-piece bushing will have an outside diameter of 1.00 inch and 
the one-piece bushing will have an outside diameter of 1.128 to 
1.130 inches.
--The one-piece bushing contains a visible chamfer in the center of 
the bushing, and the chamfer in the two-piece bushing is not visible 
when the stud is installed.
--If P/N 95643-00/-01/-02/-03 bracket assembly is installed or the 
above information cannot be utilized, the main gear side brace stud 
will need to be removed from the bracket to determine the shank 
diameter and main gear side brace stud P/N.
--P/N 95299-00 and P/N 95299-02 main gear side brace studs are 9/16-
inch in diameter.
--P/N 95643-00/-01/-02/-03 bracket assembly may have been modified 
to accommodate the 5/8-inch diameter main gear side brace stud, P/N 
78717-02.

    Issued in Kansas City, Missouri, on April 19, 1996.
Henry A. Armstrong,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-10167 Filed 4-24-96; 8:45 am]
BILLING CODE 4910-13-U