[Federal Register Volume 60, Number 235 (Thursday, December 7, 1995)]
[Proposed Rules]
[Pages 62776-62779]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-29859]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 90-CE-62-AD]


Airworthiness Directives; The New Piper Aircraft, Inc. (Formerly 
Piper Aircraft Corporation) PA31, PA31P, and PA31T Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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[[Page 62777]]


SUMMARY: This document proposes to supersede Airworthiness Directive 
(AD) 88-05-05, which currently requires the following on certain The 
New Piper Aircraft, Inc. (Piper) PA31, PA31P, and PA31T series 
airplanes: repetitively inspecting both the left and right main landing 
gear (MLG) forward sidebrace, and replacing any cracked MLG forward 
sidebrace. The Federal Aviation Administration's policy on aging 
commuter-class aircraft is to eliminate or, in certain instances, 
reduce the number of certain repetitive short-interval inspections when 
improved parts or modifications are available. The proposed action 
would retain the current repetitive inspections contained in AD 88-05-
05, and would require incorporating both a left and right MLG forward 
sidebrace of improved design as terminating action for the repetitive 
inspection requirement. The actions specified in the proposed AD are 
intended to prevent the MLG from retracting because of a cracked MLG 
forward side brace, which, if not detected and corrected, could result 
in gear collapse and loss of control of the airplane during landing 
operations.

DATES: Comments must be received on or before February 22, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 90-CE-62-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.
    Service information that relates to the proposed AD may be obtained 
from The New Piper Aircraft, Inc., Customer Services, 2926 Piper Drive, 
Vero Beach, Florida 32960. This information also 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. 90-CE-62-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. 90-CE-62-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Discussion

    The FAA has determined that reliance on critical repetitive 
inspections on aging commuter-class airplanes carries an unnecessary 
safety risk when a design change exists that could eliminate or, in 
certain instances, reduce the number of those critical inspections. In 
determining what inspections are critical, the FAA considers (1) the 
safety consequences if the known problem is not detected during the 
inspection; (2) the probability of the problem not being detected 
during the inspection; (3) whether the inspection area is difficult to 
access; and (4) the possibility of damage to an adjacent structure as a 
result of the problem.
    These factors have led the FAA to establish an aging commuter-class 
aircraft policy that requires incorporating a known design change when 
it could replace a critical repetitive inspection. With this policy in 
mind, the FAA conducted a review of existing AD's that apply to Piper 
Models PA31-350 and PA31T3 airplanes. Assisting the FAA in this review 
were (1) The New Piper Aircraft, Inc.; (2) the Regional Airlines 
Association (RAA); and (3) several operators of the affected airplanes.
    From this review, the FAA has identified AD 88-05-05, Amendment 39-
5861, as one that should be superseded with a new AD that would require 
a modification that would eliminate the need for short-interval and 
critical repetitive inspections. AD 88-05-05 currently requires the 
following on certain Piper PA31, PA31P, and PA31T series airplanes:

--Repetitively inspecting both the left and right main landing gear 
(MLG) forward sidebrace for cracks, and replacing any cracked MLG 
forward sidebrace stud. Accomplishment of the inspections required by 
AD 88-05-05 is in accordance with Piper Service Bulletin (SB) No. 845A, 
dated October 9, 1987; and
--Allowing for the provision of replacing both the left and right MLG 
forward sidebrace with a part of improved design, part number (P/N) 
85165-02 (left) and 85165-03 (right) or P/N 85166-02 (left) and 85166-
03 (right), as applicable. This installation is accomplished in 
accordance with the applicable maintenance manual.

    Based on its aging commuter-class aircraft policy and after 
reviewing all available information related to this subject including 
the referenced service information, the FAA has determined that AD 
action should be taken to eliminate the repetitive short-interval 
inspections required by AD 88-05-05, and to prevent the MLG from 
retracting because of a cracked MLG forward side brace, which, if not 
detected and corrected, could result in gear collapse and 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 PA31, PA31P, and PA31T series airplanes 
of the same type design, the proposed AD would supersede AD 88-05-05 
with a new AD that would (1) retain the requirement of repetitively 
inspecting both the left and right MLG forward sidebrace for cracks, 
and replacing any cracked MLG forward sidebrace; and (2) require 
replacing both the left and right MLG forward sidebrace with a part of 
improved design, part number (P/N) 85165-02 (left) and 85165-03 (right) 
or P/N 85166-02 (left) and 85166-03 (right), as applicable, as 
terminating action for the repetitive inspections. Accomplishment of 
the proposed inspections would be in accordance with Piper SB No. 845A, 
dated October 9, 1987. The improved MLG forward sidebrace installations 
would be accomplished in accordance 

[[Page 62778]]
with the applicable maintenance manual.
    The FAA estimates that 2,384 airplanes in the U.S. registry would 
be affected by the proposed AD, that it would take approximately 8 
workhours per airplane to accomplish the proposed replacement, and that 
the average labor rate is approximately $60 an hour. Parts cost 
approximately $1,000 per airplane (2 MLG forward sidebraces per 
airplane at approximately $500 per sidebrace). Based on these figures, 
the total cost impact of the proposed replacement on U.S. operators is 
estimated to be $3,528,320 or $1,480 per airplane. This figure is based 
on the assumption that no affected airplane owner/operator has 
accomplished the proposed replacement.
    Piper has informed the FAA that parts have been distributed to 
owners/operators to equip 2,123 of the affected airplanes (4,246 MLG 
forward sidebraces of improved design). Assuming that each set of parts 
has been installed on an affected airplane, the cost impact of the 
proposed replacement upon U.S. owners operators of the affected 
airplanes would be reduced by $3,142,040 from $3,528,320 to $386,280.
    The intent of the FAA's aging commuter airplane program is to 
ensure safe operation of commuter-class airplanes that are in 
commercial service without adversely impacting private operators. The 
FAA believes that a large number of the remaining 261 affected 
airplanes (2,384 affected airplanes--2,123 airplanes with a set of 
parts distributed) that would be affected by the proposed AD are 
operated in various types of air transportation. This includes 
scheduled passenger service, air cargo, and air taxi.
    The proposed AD would allow 1,200 hours time-in-service (TIS) after 
the effective date of the proposed AD before mandatory accomplishment 
of the design modification. The average utilization of the fleet for 
those airplanes in air transportation is between 25 to 40 hours TIS per 
week. Based on these figures, operators of commuter-class airplanes 
involved in commercial operation would have to accomplish the proposed 
modification within 7 to 12 months after the proposed AD would become 
effective. For private owners, who typically operate between 100 to 200 
hours TIS per year, this would allow 6 to 12 years before the proposed 
replacement would be mandatory.
    The FAA established the 1,200 hours TIS replacement compliance time 
based on its engineering evaluation of the problem. Among the issues 
examined during this engineering evaluation were analysis of service 
difficulty reports, the difficulty level of the inspection, and how 
critical the situation would be if cracks occurred in the subject area 
despite accomplishment of the repetitive inspections.
    Usually, the FAA establishes the mandatory design modification 
compliance time on AD's affecting aging commuter-class airplanes upon 
the accumulation of a certain number of hours TIS on the airplane. For 
this action, the FAA is proposing to mandate the modification for all 
operators ``within the next 1,200 hours TIS after the effective date of 
this AD.'' The total TIS levels of the airplane fleet vary from under 
1,000 hours TIS to over 5,000 hours TIS, and annual accumulation rates 
vary from 50 hours TIS to over 1,000 hours TIS. Establishing a long-
term set compliance time of hours TIS accumulated on Piper PA31, PA31P, 
and PA31T series airplanes (such as 5,000 hours TIS) would impose an 
undue burden on the manufacturer of having to maintain a supply of 
replacement parts for the entire fleet when many airplanes in the fleet 
may never reach this compliance time.
    Instead, the FAA believes that Piper should maintain parts for 
several years; in this case about 12 years to allow low-usage airplanes 
time to accumulate the 1,200 hours TIS after the effective date of the 
AD. The FAA has determined that the compliance time of the proposed 
rule provides the level of safety required for commuter air service 
while still minimizing the impact on the private airplane owners of 
Piper PA31, PA31P, and PA31T series airplanes.
    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 USC 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Airworthiness Directive 
(AD) 88-05-05, Amendment 39-5861, and by adding a new AD to read as 
follows:

The New Piper Aircraft, Inc. (formerly Piper Aircraft Corporation): 
Docket No. 90-CE-62-AD. Supersedes AD 88-05-05, Amendment 39-5861.

    Applicability: The following model and serial number airplanes, 
certificated in any category, that do not have left and right main 
landing gear (MLG) forward sidebraces of improved design installed, 
part number (P/N) 85165-02 (left) and 85165-03 (right) or P/N 85166-
02 (left) and 85166-03 (right).

------------------------------------------------------------------------
               Models                             Serial Nos.           
------------------------------------------------------------------------
PA31, PA31-300, and PA31-325........  31-2 through 31-8312019.          
PA31-350............................  31-5001 through 31-8553002.       
PA31P...............................  31P-2 through 31P-7730012.        

[[Page 62779]]
                                                                        
PA31P-350...........................  31P-8414001 through 31P-8414050.  
PA31T...............................  31T-7400002 through 31T-8120104.  
PA31T1..............................  31T-7804001 through 31T-8304003   
                                       and 31T-1104004 through 31T-     
                                       1104017.                         
PA31T2..............................  31T-8166001 through 31T-8166076   
                                       and 31T-1166001 through 31T-     
                                       1166008.                         
------------------------------------------------------------------------



    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 (g) 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 as indicated in the body of this AD, unless 
already accomplished.
    To prevent the MLG from retracting because of a cracked MLG 
forward side brace, which, if not detected and corrected, could 
result in gear collapse and loss of control of the airplane during 
landing operations, accomplish the following:
    (a) Within the next 100 hours time-in-service (TIS) after the 
effective date of this AD, unless already accomplished (compliance 
with AD 88-05-05), and thereafter at intervals not to exceed 100 
hours TIS until the modification required by paragraph (c) or (d) of 
this AD is incorporated, inspect (using dye penetrant methods) both 
the left and right MLG sidebrace for cracks. Accomplish the 
inspections in accordance with the INSTRUCTIONS section of Piper 
Service Bulletin No. 845A, dated October 9, 1987.
    (b) The initial dye penetrant inspection type must be utilized 
for all future repetitive inspections. Dye penetrant inspection 
types consist of Type I: fluorescent; Type II: non-fluorescent or 
visible dye; and Type III: dual sensitivity.
    (c) If cracks are found during any of the inspections required 
in paragraph (a) of this AD, prior to further flight, replace the 
cracked MLG sidebrace with a part of improved design, P/N 85165-02 
(left) or 85165-03 (right) or P/N 85166-02 (left) or 85166-03 
(right), as applicable. Accomplish this replacement in accordance 
with the applicable maintenance manual.
    (d) Within the next 1,200 hours TIS after the effective date of 
this AD, unless already accomplished as required by paragraph (c) of 
this AD, replace both the left and right MLG side brace with parts 
of improved design, P/N 85165-02 (left) and 85165-03 (right) or P/N 
85166-02 (left) and 85166-03 (right), as applicable. Accomplish 
these replacements in accordance with the applicable maintenance 
manual.
    (e) Installing both the left and right MLG side brace with parts 
of improved design, P/N 85165-02 (left) and 85165-03 (right) or P/N 
85166-02 (left) and 85166-03 (right), as applicable, as required by 
paragraph (d) of this AD is considered terminating action for the 
repetitive inspection requirement of this AD.
    (f) 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.
    (g) 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Atlanta ACO.

    Note 3: Alternative methods of compliance approved in accordance 
with AD 88-05-05 (superseded by this AD) are not considered approved 
for this AD.

    (h) All persons affected by this directive may obtain copies of 
the document referred to herein upon request to The New Piper 
Aircraft, Inc., 2926 Piper Drive, Vero Beach, Florida 32960; or may 
examine this document at the FAA, Central Region, Office of the 
Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, 
Missouri 64106.
    (i) This amendment supersedes AD 88-05-05, Amendment 39-5861. 
    Issued in Kansas City, Missouri, on December 1, 1995.
 John R. Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-29859 Filed 12-6-95; 8:45 am]
BILLING CODE 4910-13-U