[Federal Register Volume 60, Number 235 (Thursday, December 7, 1995)]
[Proposed Rules]
[Pages 62779-62782]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-29860]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 90-CE-63-AD]


Airworthiness Directives; The New Piper Aircraft, Inc. (Formerly 
Piper Aircraft Corporation) Models PA31, PA31-300, PA31-325, and PA31-
350 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to supersede Airworthiness Directive 
(AD) 80-14-06, which currently requires the following on The New Piper 
Aircraft, Inc. (Piper) Models PA31, PA31-300, PA31-325, and PA31-350 
airplanes: repetitively inspecting the outboard flap tracks, wing rib 
flanges, and the rear spar web at Wing Station (WS) 147.5 on each wing, 
and modifying the area at WS 147.5 on both wings if any cracks are 
found as terminating action for the repetitive inspection requirement. 
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 80-14-06, and would 
require modifying the area at WS 147.5 on both wings as terminating 
action for the repetitive inspections. The actions specified in the 
proposed AD are intended to prevent structural failure under certain 
load conditions caused by cracked areas at WS 147.5, which, if not 

[[Page 62780]]
detected and corrected, could result in loss of control of the 
airplane.

DATES: Comments must be received on or before February 23, 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-63-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-63-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-63-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 80-14-06, Amendment 39-
3805, 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 80-14-06 currently requires the 
following on Piper Models PA31, PA31-300, PA31-325, and PA31-350 
airplanes:

--Repetitively inspecting the outboard flap tracks, wing rib flanges, 
and the rear spar web at Wing Station (WS) 147.5 on each wing and 
modifying the area at WS 147.5 on both wings if any cracks are found as 
terminating action for the repetitive inspection requirement; and
--Allowing for the provision of modifying the area at WS 147.5 on both 
wings as terminating action for the repetitive inspection requirement.

    Piper Service Bulletin (SB) No. 647A, dated November 24, 1980, 
references Kit 763 986, which, when incorporated, provides a 
modification of the area at WS 147.5 on both wings that would eliminate 
the need for the repetitive inspection requirement of AD 80-14-06. Kit 
763 986 also contains procedures for incorporating this modification.
    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 80-14-06, and to prevent structural failure 
under certain load conditions caused by cracked areas at WS 147.5, 
which, if not detected and corrected, could result in loss of control 
of the airplane.
    Since an unsafe condition has been identified that is likely to 
exist or develop in other Piper Models PA31, PA31-300, PA31-325, and 
PA31-350 airplanes of the same type design, the proposed AD would 
supersede AD 80-14-06 with a new AD that would (1) retain the 
requirement of repetitively inspecting the outboard flap track, wing 
rib flanges, and the rear wing web at WS 147.5, and, if any cracks are 
found, modifying the area of WS 147.5 by incorporating Piper Kit 763 
986 as terminating action for the repetitive inspection requirement; 
and (2) require incorporating Piper Kit 763 986 at a specified hours 
TIS time-period for airplanes where no cracks were found during the 
inspections as terminating action for the repetitive inspection 
requirement. Accomplishment of the proposed modification would be in 
accordance with the instructions included with Piper Kit 763 986, as 
referenced in Piper SB No. 647A, dated November 24, 1980.
    The FAA estimates that 2,906 airplanes in the U.S. registry would 
be affected by the proposed AD, that it would take approximately 30 
workhours per airplane to accomplish the proposed modification, and 
that the average labor rate is approximately $60 an hour. Parts cost 
approximately $468 per airplane. Based on these figures, the total cost 
impact of the proposed modification on U.S. operators is estimated to 
be $6,590,808 or $2,268 per airplane.
    Piper has informed the FAA that parts have been distributed to 
enough owners/operators to equip 234 of the affected airplanes. 
Assuming that each set of parts has been installed on an affected 
airplane, the cost impact of the proposed AD upon U.S. owners operators 
of the affected airplanes would be reduced by $530,712 from $6,590,808 
to $6,060,096.
    The intent of the FAA's aging commuter airplane program is to 
ensure safe operation of commuter-class 

[[Page 62781]]
airplanes that are in commercial service without adversely impacting 
private operators. The FAA believes that a large number of the 
remaining 2,672 affected airplanes (2,906 airplanes--234 sets 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 1,000 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 6 to 10 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 5 to 10 years before the 
proposed modification would be mandatory.
    The FAA established the 1,000 hours TIS modification 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 1,000 hours TIS after the effective date of 
this AD.'' The total TIS levels of the airplane fleet varies 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 a Piper Model 
PA31, PA31-300, PA31-325, or PA31-350 airplane (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 10 years to allow low-usage airplanes 
time to accumulate the ``1,000 hours 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 Models PA31, PA31-300, PA31-325, and PA31-350 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) 80-14-06, Amendment 39-3805, and by adding a new AD to read as 
follows:

The New Piper Aircraft, Inc. (formerly Piper Aircraft Corporation): 
Docket No. 90-CE-63-AD. Supersedes AD 80-14-06, Amendment 39-3805.

    Applicability: The following model and serial number airplanes, 
certificated in any category, that do not have Piper Kit 763 986 
incorporated in the area of Wing Station (WS) 147.5:

------------------------------------------------------------------------
               Models                             Serial Nos.           
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PA31 and PA31-300...................  31-2 through 31-8012010.          
PA31-325............................  31-7512006 through 31-8012010.    
PA31-350............................  31-5001 through 31-8052025.       
------------------------------------------------------------------------

    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 (f) 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 structural failure under certain load conditions 
caused by cracked areas at WS 147.5, which, if not detected and 
corrected, could result in loss of control of the airplane, 
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 80-14-06), and thereafter at 
intervals not to exceed 100 hours TIS until the modification 
required by paragraph (b) or (c) of this AD is incorporated, inspect 
the 

[[Page 62782]]
outboard flap tracks, wing rib flanges, and the rear spar web on both 
wings in the area of WS 147.5 by accomplishing the following:
    (1) Lower the flaps to 40 degrees.
    (2) Inspect the attachment of the flap track rib to the rear 
spar on the inboard and outboard sides of the flap track using 10-
power magnification.
    (3) Remove the rectangular access plate from the bottom wing 
skin. The rectangular access plate is located forward of the wing 
spar at WS 153.
    (4) Inspect the WS 147.5 rib attachment angle using 10-power 
magnification.

    Note 2: The 100-hour TIS repetitive inspection interval was 
established to coincide with regularly scheduled maintenance.

    (b) If cracks are found during any of the inspections required 
in paragraph (a) of this AD, prior to further flight, incorporate 
Piper Kit 763 986 in accordance with the instructions included with 
this kit, as referenced in Piper Service Bulletin (SB) No. 647A, 
dated November 24, 1980.
    (c) Within the next 1,000 hours TIS after the effective date of 
this AD, unless already accomplished as required by paragraph (b) of 
this AD, incorporate Piper Kit 763 986 in the area of WS 147.5. 
Accomplish this action in accordance with the instructions included 
with this kit, as referenced in Piper SB No. 647A, dated November 
24, 1980.
    (d) Incorporating Piper Kit 763 986 as required by paragraphs 
(b) and (c) of this AD is considered terminating action for the 
repetitive inspection requirement of this AD.
    (e) 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.
    (f) 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.

    Note 4: Alternative methods of compliance approved in accordance 
with AD 80-14-06 (superseded by this action) are not considered 
approved as alternative methods of compliance with this AD.

    (g) 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.
    (h) This amendment supersedes AD 80-14-06, Amendment 39-3805.

    Issued in Kansas City, Missouri, on December 1, 1995.
John R. Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-29860 Filed 12-6-95; 8:45 am]
BILLING CODE 4910-13-U