[Federal Register Volume 63, Number 99 (Friday, May 22, 1998)]
[Proposed Rules]
[Pages 28294-28299]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-13656]


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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. PA-24, PA-
28R, PA-30, PA-32R, PA-34, and PA-39 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to revise Airworthiness Directive (AD) 
97-01-01, which currently requires repetitively inspecting the main 
gear sidebrace studs for cracks on The New Piper Aircraft, Inc. (Piper) 
Models PA-24, PA-28R, PA-30, PA-32R, PA-34, and PA-39 series airplanes, 
and replacing any main gear sidebrace stud found cracked. The Federal 
Aviation Administration (FAA) has approved certain alternative methods 
of compliance (AMOC) for AD 97-01-01, and has determined that these 
AMOC's should be incorporated into the AD. The proposed AD would retain 
all the actions of AD 97-01-01, and would incorporate certain AMOC's as 
a way of accomplishing the actions specified in AD 97-01-01. The 
actions specified by the proposed AD are intended to prevent a main 
landing gear collapse caused by main gear sidebrace stud cracks, which 
could result in loss of control of the airplane during landing 
operations.

DATES: Comments must be received on or before July 23, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional 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: Mr. William O. Herderich, Aerospace 
Engineer, FAA, Atlanta Certification Office, One Crown Center, 1895 
Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone: (770) 
703-6084; facsimile: (770) 703-6097.

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

[[Page 28295]]

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 Regional Counsel, Attention: 
Rules Docket No. 96-CE-09-AD, Room 1558, 601 E. 12th Street, Kansas 
City, Missouri 64106.

Discussion

    AD 97-01-01, Amendment 39-9872 (62 FR 10, January 2, 1997), 
currently requires repetitively inspecting the main gear sidebrace 
studs for cracks on Piper Models PA-24, PA-28R, PA-30, PA-32R, PA-34, 
and PA-39 series airplanes, and replacing any main gear sidebrace stud 
found cracked. The actions specified by AD 97-01-01 are intended to 
prevent a main landing gear collapse caused by main gear sidebrace stud 
cracks, which could result in loss of control of the airplane during 
landing operations.

Actions Since Issuance of Previous Rule

    Since issuance of AD 97-01-01, the FAA has approved alternative 
methods of compliance for modifying the existing bracket assembly as 
terminating action for the repetitive inspection requirement of that 
AD.

The FAA's Determination

    After examining the circumstances and reviewing all available 
information related to the subject described above, the FAA has 
determined that (1) the alternative methods of compliance approved for 
modifying the existing bracket assembly should be made available as an 
option of complying with the current AD; and (2) AD action should be 
taken to prevent a main landing gear collapse caused by main gear 
sidebrace stud cracks, which could result in loss of control of the 
airplane during landing operations.

Explanation of the Provisions of the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other Piper Models PA-24, PA-28R, PA-30, PA-32R, 
PA-34, and PA-39 series airplanes of the same type design, the FAA is 
proposing to revise AD 97-01-01. The proposed AD would retain all the 
actions of AD 97-01-01, and would incorporate alternative methods of 
compliance for modifying the existing bracket assembly, as terminating 
action for the repetitive inspection requirement of that AD.

Cost Impact

    The cost impact of the proposed AD would be the same as is 
currently required by AD 97-01-01. As a courtesy, the FAA is reprinting 
that cost information in the following paragraphs.
    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 (which was superseded by AD 97-01-01). The only 
difference between the proposed AD and AD 95-20-07 is the addition of 
an inspection-terminating modification option and the elimination of 
(from the ``Applicability'' section of the AD) certain airplanes that 
incorporate a certain main side brace stud assembly. The proposed AD 
would also not provide any additional cost impacts over that already 
required by AD 95-20-07.

Regulatory Impact

    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 
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 
97-01-01, Amendment 39-9872 (62 FR 10, January 2, 1997), and by adding 
a new AD to read as follows:

The New Piper Aircraft, Inc.: Docket No. 96-CE-09-AD; Revises AD 97-
01-01, Amendment 39-9872.

    Applicability: The following airplane models and serial numbers, 
certificated in any category:
    1. All serial numbers of Models PA-24, PA-24-250, PA-24-260, PA-
24-400, PA-30, and PA-39 airplanes;
    2. The following model and serial number airplanes that are not 
equipped with a Piper part number (P/N) 78717-02 (or FAA-approved 
equivalent part number) main gear sidebrace stud in both right and 
left main gear sidebrace bracket assemblies:

------------------------------------------------------------------------
                 Model                             Serial Nos.          
------------------------------------------------------------------------
PA-28R-180............................  28R-30002 through 28R-31135, and
                                         28R-7130001 through 28R-       
                                         7130013.                       
PA-28R-200............................  28R-35001 through 28R-35820, and
                                         28R-7135001 through 28R-       
                                         7635539.                       
PA-28R-201............................  28R-7737002 through 28R-7737096.
PA-28R-201T...........................  28R-7703001 through 28R-7703239.
PA-32R-300............................  32R-7680001 through 32R-7780444.

[[Page 28296]]

                                                                        
PA-34-200.............................  All serial numbers.             
PA-34-200T............................  34-7570001 through 34-7770372.  
------------------------------------------------------------------------

    Note 1: P/N 78717-02 sidebrace stud was installed at manufacture 
on Piper Model PA-34-200T 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 PA-28R-180, PA-28R-200, PA-28R-201, 
PA-28R-201T, PA-32R-300, PA-34-200, and PA-34-200T airplanes: Within 
the next 100 hours time-in-service (TIS) after the effective date of 
this AD; or, if the main gear sidebrace 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 PA-24, PA-24-250, PA-24-260, PA-24-
400, PA-30, and PA-39 airplanes: Within the next 100 hours TIS after 
the effective date of this AD; or, if the main gear sidebrace 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 
sidebrace stud cracks, which 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 4: (A), (B), (C), etc.

    Level 2, Level 3, and Level 4 structures are designations of the 
Level 1 paragraph they immediately follow.
    (a) Remove both the left and right main gear sidebrace studs 
from the airplane in accordance with the instructions contained in 
the Landing Gear section of the maintenance manual, and inspect each 
main gear sidebrace stud for cracks, using Type I (fluorescent) 
liquid penetrant or magnetic particle inspection methods. Figure 1 
of this AD depicts the area of the sidebrace stud shank where the 
sidebrace stud is to be inspected.

    Note 4: All affected Models PA-24 and PA-24-250 airplanes were 
equipped at manufacture with P/N 20829-00 main gear sidebrace studs. 
All affected Models PA-24-260, PA-24-400, PA-30, and PA-39 airplanes 
were equipped at manufacture with P/N 22512-00 main gear sidebrace 
studs. The Appendix included with this AD contains information on 
determining the P/N of the bracket assembly (which contains the main 
gear side brace stud) on the affected PA-28R, PA-32R, and PA-34 
series airplanes.

BILLING CODE 4910-13-U

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[GRAPHIC] [TIFF OMITTED] TP22MY98.001



BILLING CODE 4910-13-C

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    (1) For any main gear sidebrace 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 part number) 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 PA-28R-180, PA-28R-200, PA-28R-201, 
PA-28R-201T, PA-32R-300, PA-34-200, and PA-34-200T airplanes, the 9/
16-inch main gear sidebrace studs (P/N 95299-00, 95299-02, or P/N 
67543, as applicable) are no longer manufactured. Install a new main 
gear sidebrace 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 PA-28R-180, PA-28R-200, PA-28R-
201, PA-28R-201T, PA-32R-300, PA-34-200, and PA-34-200T airplanes, 
ream the existing two-piece bushings to an inside diameter of .624-
inch to .625-inch, chamfer the head side of the bushing to 
accommodate the radius in the shank of the main gear sidebrace stud, 
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 bushings are loose), then install a main gear 
sidebrace bracket assembly, P/N 95643-06, P/N 95643-07, P/N 95643-
08, or P/N 95643-09, as applicable. Models PA-28R-180 and PA-28R-200 
with serial numbers as specified in the Appendix to this AD may be 
equipped with a bracket casting identified with casting number 
67073-2 or 67073-3 and may require the following modification to P/N 
78717-02 for proper installation:
    (A) Reduce the length of the stud to 1.688 <plus-minus> 0.15 
inches;
    (B) Add additional rolled threads to 1.125 <plus-minus> .015 
inches from the flange. Note that the stud is heat treated to 180 to 
200 ksi; and
    (C) Drill an additional roll pin hole 90 degrees to the existing 
hole, and approximately 1.480 inches from the flange.
    (iv) No repetitive inspections will be required by this AD when 
a P/N 78717-02 (or FAA-approved equivalent part number) main gear 
sidebrace stud is installed in the existing bracket assembly or when 
a bracket assembly, P/N 95643-07 (or FAA-approved equivalent part 
number), P/N 95643-08 (or FAA-approved equivalent part number), or 
P/N95643-09 (or FAA-approved equivalent part number), as applicable, 
is installed.
    (2) For any main gear sidebrace 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 sidebrace 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       Model airplanes    
      Part number installed          interval         installed on      
                                     (hours)                            
------------------------------------------------------------------------
20829-00 (Piper parts) or FAA-           1,000  PA-24 and PA-24-250.    
 approved equivalent part number.                                       
22512-00 (Piper parts) or FAA-           1,000  PA-24-260, PA-24-400, PA-
 approved equivalent part number.                30, and PA-39.         
95299-00 or 95299-02 (Piper                500  PA-28R-180 and PA-28R-  
 parts) or FAA-approved                          200 not equipped with  
 equivalent part number.                         casting number 67073-2 
                                                 or 67073-3, PA-28R-201,
                                                 PA-28R-201T, PA-32R-   
                                                 300, PA-34-200, and PA-
                                                 34-200T.               
67543 (Piper parts) or FAA-                500  PA-28R-180 and PA-28R-  
 approved equivalent part number.                200 equipped with      
                                                 casting number 67073-02
                                                 or 67073-03.           
------------------------------------------------------------------------

    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 PA-24, PA-
30, and PA-39 series airplanes.

    (c) Owners/operators of the affected Models PA-28R-180, PA-28R-
200, PA-28R-201, PA-28R-201T, PA-32R-300, PA-34-200, and PA-34-200T 
airplanes may accomplish one of the following at any time to 
terminate the repetitive inspection requirement of this AD:
    (1) Install a main gear sidebrace bracket assembly, P/N 95643-06 
(or FAA-approved equivalent part number), P/N 95643-07 (or FAA-
approved equivalent part number), P/N 95643-08 (or FAA-approved 
equivalent part number), or P/N 95643-09 (or FAA-approved equivalent 
part number), as applicable, which contains the 5/8-inch diameter 
main gear sidebrace stud, P/N 78717-02 (or FAA-approved equivalent 
part number), and the one-piece bushing, P/N 67026-12 (or FAA-
approved equivalent part number). Accomplish these installations in 
accordance with the instructions contained in the Landing Gear 
section of the applicable maintenance manual; or
    (2) Ream the existing two-piece bushings to an inside diameter 
of .624-inch to .625-inch, chamfer the head side of the bushing to 
accommodate the radius in the shank of the main gear sidebrace stud, 
and install the 5/8-inch stud, P/N 78717-02 (or FAA-approved 
equivalent part number). 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 bushings are 
loose), then install a main gear sidebrace bracket assembly, P/N 
95643-06 (or FAA-approved equivalent part number), P/N 95643-07 (or 
FAA-approved equivalent part number), P/N 95643-08 (or FAA-approved 
equivalent part number), or P/N 95643-09 (or FAA-approved equivalent 
part number), as applicable. Models PA-28R-180 and PA-28R-200 with 
serial numbers as specified in the Appendix to this AD may be 
equipped with a bracket casting identified with casting number 
67073-2 or 67073-3 and may require the following modification to P/N 
78717-02 (or FAA-approved equivalent part number) for proper 
installation:
    (i) Reduce the length of the stud to 1.688 <plus-minus> 0.15 
inches;
    (ii) Add additional rolled threads to 1.125 <plus-minus> .015 
inches from the flange. Note that the stud is heat treated to 180 to 
200 ksi; and
    (iii) Drill an additional roll pin hole 90 degrees to the 
existing hole, and approximately 1.480 inches from the flange.
    (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), One Crown Center, 1895 Phoenix 
Boulevard, suite 450, Atlanta, Georgia 30349.
    (1) The request shall be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Atlanta ACO.
    (2) Alternative methods of compliance approved in accordance 
with AD 97-01-01, Amendment 39-9872 (revised by this action), or AD 
95-20-07, Amendment 39-9386 (superseded by AD 97-01-01), are 
considered approved as alternative methods of compliance with this 
AD.

    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) Information related to this AD may be inspected at the FAA, 
Central Region, Office of the Regional Counsel, Room 1558, 601 E. 
12th Street, Kansas City, Missouri.

[[Page 28299]]

    (g) This amendment revises AD 97-01-01, Amendment 39-9872, which 
superseded AD 95-20-07, Amendment 39-9386.

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

--The P/N 95643-00/-01/-02/-03 bracket assembly contains the 9/16-
inch diameter main gear sidebrace 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 sidebrace 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. This measurement is not valid for the following 
airplanes:

------------------------------------------------------------------------
                 Model                             Serial Nos.          
------------------------------------------------------------------------
PA-28R-180............................  28R-30004 through 28-31270.     
PA-28R-200............................  28R-35001 through 28R-35820, and
                                         28R-7135001 through 28R-       
                                         7135062.                       
------------------------------------------------------------------------

    The main gear sidebrace studs on these airplanes will require 
removal to determine the P/N installed.

--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 sidebrace stud 
will need to be removed from the bracket to determine the shank 
diameter and main gear sidebrace stud P/N.
--P/N 95299-00 and P/N 95299-02 main gear sidebrace studs are 9/16-
inch in diameter.
--P/N 78717-00 main gear sidebrace studs are 5/8-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 sidebrace stud, P/N 
78717-02.
--The embossed number of 95363 on the bracket forging is not the 
bracket assembly P/N.
--The bracket assemblies identified with casting number 67073-2 or 
67073-3 contain a 9/16-inch diameter main gear sidebrace stud, P/N 
67543, and two-piece bushing, P/N 67026-2 and 67026-3.
--Model PA-28R-180 airplanes, serial numbers 28R-30004 through 28R-
31270; and Model PA-28R-200 airplanes, serial numbers 28R-35001 
through 28R-35820 and 28R-7135001 through 28R-7135062, are equipped 
from the factory with bracket assemblies identified with casting 
number 67073-2 and 67073-3.
--P/N 67543 main gear sidebrace studs are 9/16-inch in diameter.

    Issued in Kansas City, Missouri, on May 14, 1998.
Michael Gallagher,
Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 98-13656 Filed 5-21-98; 8:45 am]
BILLING CODE 4910-13-U