[Federal Register Volume 61, Number 243 (Tuesday, December 17, 1996)]
[Proposed Rules]
[Pages 66238-66240]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-31950]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-CE-44-AD]
RIN 2120-AA64


Airworthiness Directives; Jetstream Aircraft Limited HP137 Mk1, 
Jetstream Series 200, and Jetstream Models 3101 and 3201 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); Reopening of 
the comment period.

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SUMMARY: This document proposes to revise an earlier proposed 
airworthiness directive (AD) that would have required the following on 
Jetstream Aircraft Limited (JAL) HP137 Mk1, Jetstream series 200, and 
Jetstream Models 3101 and 3201 airplanes: repetitively inspecting the 
main landing gear (MLG) pintle to cylinder interface for cracks, and 
replacing any MLG cylinder that has a crack of any length. The proposed 
AD results from reports of MLG cracks in the area of the pintle to 
cylinder interface on three of the affected airplanes. Since 
publication of that proposal, the Federal Aviation Administration (FAA) 
has determined

[[Page 66239]]

that the proposed action is still a valid safety issue, but that more 
stringent repetitive inspection intervals should be established than 
what was earlier proposed. This proposed AD revises the previous 
proposal by incorporating this change. The actions specified by the 
proposed AD are intended to prevent failure of the MLG caused by cracks 
in the pintle to cylinder interface area, which could result in loss of 
control of the airplane during landing operations. Since the comment 
period for the previous proposal has closed and the change described 
above goes beyond the scope of what was previously proposed, the FAA is 
allowing additional time for the public to comment.

DATES: Comments must be received on or before February 28, 1997.

ADDRESSES: Submit comments in triplicate to the FAA, Central Region, 
Office of the Assistant Chief Counsel, Attention: Rules Docket No. 95-
CE-44-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 applies to the proposed AD may be obtained 
from Jetstream Aircraft Limited, Prestwick International Airport, 
Ayrshire, KA9 2RW, Scotland; telephone (44-292) 79888; facsimile (44-
292) 79703; or Jetstream Aircraft Inc., Librarian, P.O. Box 16029, 
Dulles International Airport, Washington, D.C. 20041-6029; telephone 
(703) 406-1161; facsimile (703) 406-1469. This information also may be 
examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. Tom Rodriguez, Program Manager, 
Brussels Aircraft Certification Division, FAA, Europe, Africa, and 
Middle East Office, c/o American Embassy, B-1000 Brussels, Belgium; 
telephone (32 2) 508.2715; facsimile (32 2) 230.6899; or Mr. S.M. 
Nagarajan, Project Officer, Small Airplane Directorate, Aircraft 
Certification Service, FAA, 1201 Walnut, suite 900, Kansas City, 
Missouri 64106; telephone (816) 426-6932; facsimile (816) 426-2169.

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 supplemental 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 supplemental notice must submit a self-
addressed, stamped postcard on which the following statement is made: 
``Comments to Docket No. 95-CE-44-AD.'' The postcard will be date 
stamped and returned to the commenter.

Availability of Supplemental NPRM

    Any person may obtain a copy of this supplemental NPRM by 
submitting a request to the FAA, Central Region, Office of the 
Assistant Chief Counsel, Attention: Rules Docket No. 95-CE-44-AD, Room 
1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Events Leading to This Action

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to certain JAL HP137 
Mk1, Jetstream series 200, and Jetstream Models 3101 and 3201 airplanes 
was published in the Federal Register on September 19, 1995 (60 FR 
48429). The notice of proposed rulemaking (NPRM) proposed to require 
repetitively inspecting (using non-destructive testing eddy current 
methods) the MLG pintle to cylinder interface for cracks, and replacing 
any MLG cylinder that has a crack exceeding certain limits. 
Accomplishment of the proposed inspections as specified in the NPRM 
would be in accordance with Jetstream Alert Service Bulletin 32-A-JA 
941245, Revision 2, dated March 28, 1995, and AP Precision Hydraulics 
Ltd. Service Bulletin 32-56, Revision 3, dated February 1995.
    Interested persons were afforded an opportunity to participate in 
the making of this amendment. One comment was received in favor of the 
proposed rule and no comments were received regarding the FAA's 
determination of the cost to the public.
    The original NPRM, if followed with a final rule, would have 
allowed continued flight if cracks were found in the MLG pintle to 
cylinder interface when the cracks did not exceed certain limits. The 
FAA has recently established a policy to disallow airplane operation 
when known cracks exist in primary structure (the MLG pintle to 
cylinder interface is considered primary structure). For this reason, 
the FAA issued a supplemental NPRM on March 19, 1996 (61 FR 12051, 
March 25, 1996) that proposed the same actions as the original 
proposal, but proposed to require the MLG cylinder to be replaced if 
any cracks are found, not just if cracks are found that exceed certain 
limits.
    Since publication of the previous supplemental NPRM, the FAA has 
re-examined all information related to this subject and determined that 
the actions proposed in the proposal are a valid safety issue, but that 
more stringent repetitive inspection intervals should be established. 
Specifically, the MLG pintle to cylinder interface would be inspected 
initially ``upon accumulating 8,000 landings on an affected MLG * * *'' 
(instead of 8,500 landings), ``* * * and, thereafter at intervals not 
to exceed 1,200 landings * * *'' (instead of 4,000 landings). The more 
stringent inspection intervals were based on an analysis done by JAL 
and subsequently evaluated and approved by the FAA.

Applicable Service Information

    JAL has issued Jetstream Service Bulletin 32-JA 960142, dated March 
15, 1996. This service bulletin specifies procedures for accomplishing 
the proposed inspections using fluorescent penetrant methods. The FAA 
has included this inspection method as an alternative to the non-
destructive testing eddy current inspection.

The FAA's Determination

    The revision of the previous supplemental NPRM would require more 
stringent repetitive inspection intervals of the MLG pintle to cylinder 
interface for JAL HP137 Mk1, Jetstream series 200, and Jetstream Models 
3101 and 3201 airplanes. Since these actions go beyond the scope of 
what was already proposed and the comment period for the previous 
supplemental NPRM has closed, the FAA has determined that the public 
should have the opportunity to comment on the proposal as amended. 
Therefore, the FAA is issuing this supplemental NPRM to allow all 
interested persons a further opportunity to participate in the making 
of this amendment.

[[Page 66240]]

Cost Impact

    The FAA estimates that 250 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 6 
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 $90,000. This figure does not take into 
account the cost of repetitive inspections or the cost of replacement 
MLG cylinders if cracks are found. The FAA has no way of determining 
the number of repetitive inspections each owner/operator would incur 
over the life of the airplane or the number of MLG cylinders that may 
be found cracked during the inspections proposed by this action.

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 USC 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
(AD) to read as follows:

Jetstream Aircraft Limited: Docket No. 95-CE-44-AD.

    Applicability: HP 137 Mk1, Jetstream series 200, and Jetstream 
Models 3101 and 3201 airplanes (all serial numbers), certificated in 
any category, that are equipped with one of the following main 
landing gear (MLG) part numbers:

1863
1863/4C
1864/4B
BOOA702851A
BOOA703065A
BOOA702926A
BO1A703066A
1863/4A,
1864
1864/4C
BOOA702925A
BO1A703065A
BO1A702926A
BOOA703031A
1863/4B
1864/4A
BOOA702850A
B01A702925A
BOOA703030A
BOOA703066A

    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 (d) 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 upon accumulating 8,000 
landings on an affected MLG or within the next 100 landings after 
the effective date of this AD, whichever occurs later, unless 
already accomplished, and thereafter at intervals not to exceed 
1,200 landings accumulated on an affected MLG.
    Note 2: If the number of landings is unknown, hours time-in-
service (TIS) may be used by multiplying the number of hours TIS by 
0.75. If hours TIS are utilized to calculate the number of landings, 
this would make the AD effective ``initially upon accumulating 
10,667 hours TIS on an affected MLG or within the next 133 hours TIS 
after the effective date of this AD, whichever occurs later, and 
thereafter at intervals not to exceed to 1,600 hours TIS accumulated 
on an affected MLG.''

    To prevent failure of the MLG caused by cracks in the pintle to 
cylinder interface area, which could result in loss of control of 
the airplane during landing operations, accomplish the following:
    (a) Inspect the MLG pintle to cylinder interface for cracks in 
accordance with one of the following:
    (1) Using non-destructive testing (NDT) eddy current methods, in 
accordance with AP Precision Hydraulics Ltd. Service Bulletin 32-56, 
Revision 3, dated February 1995; or
    (2) Using fluorescent penetrant methods, in accordance with 
APPENDIX 1 in Jetstream Service Bulletin 32-JA 960142, dated March 
15, 1996.
    (b) If any crack is found during any inspection required by this 
AD, prior to further flight, replace the MLG cylinder with a new 
part. Replacing the MLG cylinder does not eliminate the repetitive 
inspection requirement of this AD.

    Note 3: The ``prior to further flight'' replacement compliance 
time required by this AD if a MLG cylinder is cracked is different 
from the compliance time referenced in Jetstream Alert Service 
Bulletin 32-A-JA 941245; and AP Precision Hydraulics Ltd. Service 
Bulletin 32-56, Revision 3, dated February 1995. This AD takes 
precedence over any service information.

    (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 and repetitive compliance times that provides an equivalent 
level of safety may be approved by the Manager, Brussels Aircraft 
Certification Division, Europe, Africa, Middle East office, FAA, c/o 
American Embassy, B-1000 Brussels, Belgium. The request should be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Brussels Aircraft 
Certification Division.

    Note 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Brussels Aircraft Certification Division.

    (e) All persons affected by this directive may obtain copies of 
the documents referred to herein upon request to Jetstream Aircraft 
Limited, Manager Product Support, Prestwick Airport, Ayrshire, KA9 
2RW Scotland; or Jetstream Aircraft Inc., Librarian, P.O. Box 16029, 
Dulles International Airport, Washington, DC 20041-6029; or may 
examine these documents at the FAA, Central Region, Office of the 
Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, 
Missouri 64106.

    Issued in Kansas City, Missouri, on December 9, 1996.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 96-31950 Filed 12-16-96; 8:45 am]
BILLING CODE 4910-13-U