95-20004. Airworthiness Directives; Jetstream Aircraft Limited Model 3201 Airplanes

[Federal Register Volume 60, Number 156 (Monday, August 14, 1995)]
[Proposed Rules]
[Pages 41868-41870]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-20004]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-CE-26-AD]


Airworthiness Directives; Jetstream Aircraft Limited Model 3201 
Airplanes

agency: Federal Aviation Administration, DOT.

action: Notice of proposed rulemaking (NPRM).

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summary: This document proposes to adopt a new airworthiness directive 
(AD) that would apply to certain Jetstream Aircraft Limited (JAL) Model 
3201 airplanes. The proposed action would require repetitively 
inspecting the main landing gear (MLG) bay forward lower edge wing skin 
structure for cracks, replacing any cracked doubler with a joggled 
doubler of improved design to reinforce the area and prevent future 
cracking, and eventually incorporating these doublers on all affected 
airplanes. Cracking found at the MLG bay forward lower edge wing skin 
structure during fatigue testing of the JAL Model 3201 airplanes 
prompted the proposed action. The actions specified by the proposed AD 
are intended to prevent the MLG bay forward lower edge wing skin 
structure from cracking, which, if not detected and corrected, could 
cause failure of the wing structure and loss of control of the 
airplane.

dates: Comments must be received on or before October 8, 1995.

addresses: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Assistant Chief 
Counsel, Attention: Rules Docket No. 95-CE-26-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 [phone]; facsimile (44-
292) 79703; or Jetstream Aircraft Inc., Librarian, P.O. Box 16029, 
Dulles International Airport, Washington, DC 20041-6029; telephone 
[phone]; facsimile [phone]. This information also may be 
examined at the Rules Docket at the address above.

for further information contact: Mr. Raymond A. Stoer, Program Officer, 
Brussels Aircraft Certification Office, FAA, Europe, Africa, and Middle 
East Office, c/o American Embassy, B-1000 Brussels, Belgium; telephone 
[phone]; facsimile [phone]; or Mr. Marvin R. Nuss, 
Project Officer, Small Airplane Directorate, Airplane Certification 
Service, FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64105; 
telephone [phone]; facsimile [phone].

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 95-CE-26-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. 95-CE-26-AD, room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Discussion

    The Civil Airworthiness Authority (CAA), which is the airworthiness 
authority for the United Kingdom, recently notified the FAA that an 
unsafe condition may exist on certain JAL Model 3201 airplanes. The CAA 
advises that cracks may develop in the MLG bay forward lower edge wing 
skin structure adjacent to the main spar. While 

[[Page 41869]]
undergoing fatigue tests of this airplane model, Jetstream discovered 
the tendency for cracking in this area.
    JAL has issued Jetstream Service Bulletin (SB) 57-A-JA920540; 
Original Issue September 1, 1992, which specifies procedures for 
inspecting the MLG bay forward lower edge wing skin structure for 
cracks, and if cracks are found, replacing the cracked doubler with a 
new joggled doubler of an improved design.
    In order to assure the continued airworthiness of these airplanes 
in the United Kingdom, the CAA classified this service bulletin as 
mandatory. The CAA classifying a service document as mandatory is the 
same for airplanes registered in the United Kingdom as the FAA issuing 
an AD for airplanes registered in the United States.
    This airplane model is manufactured in the United Kingdom and is 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) and the applicable bilateral airworthiness agreement between the 
United States and the United Kingdom.
    Pursuant to this bilateral airworthiness agreement, the CAA has 
kept the FAA informed of the situation described above. The FAA has 
examined the findings of the CAA, reviewed all available information, 
and determined that AD action is necessary for products of this type 
design that are certificated for operation in the United States.
    Since an unsafe condition has been identified that is likely to 
exist or develop in other Jetstream Model 3201 airplanes of the same 
type design, the proposed AD would require repetitively inspecting the 
MLG bay forward lower edge wing skin structure adjacent to the main 
spar for cracks. If cracks are found, replace the cracked doubler with 
a joggled doubler of improved design to reinforce the area and prevent 
future cracking. Accomplishment of the proposed action would be in 
accordance with Jetstream Service Bulletin 57-A-JA920540; Original 
Issue September 1, 1992.
    The proposed action would be consistent with the FAA's aging 
commuter-class aircraft policy. This policy simply states that reliance 
on critical repetitive inspections carries an unnecessary safety risk 
when a design change exists that could eliminate or, in certain 
instances, reduce the number of those critical inspections. Therefore, 
the proposed action, if incorporated as a final rule, would be 
consistent with the FAA's commuter-class aircraft policy.
    The FAA estimates that 134 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 35 
workhours per airplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts will be provided 
by the manufacturer at no cost to the owners/operators. Based on these 
figures, the total cost impact of the proposed AD on U.S. operator is 
estimated to be $281,400. This figure is based on the assumption that 
all of the affected airplanes do not have the new joggled doublers 
installed and that none of the owners/operators of the affected 
airplanes have replaced the doublers.
    Jetstream has informed the FAA that parts have been distributed to 
equip approximately 5 airplanes. Assuming that these distributed parts 
are incorporated on the affected airplanes, the cost of the proposed AD 
would be reduced by $10,500 from $281,400 to $270,900.
    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); 40101, 40113, 44701.


Sec. 39.13  [AMENDED]

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

Jetstream Aircraft Limited: Docket No. 95-CE-26-AD.

    Applicability: Model 3201 airplanes (serial numbers 790 through 
969), certificated in any category.

    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 use the authority 
provided in paragraph (e) of this AD to request approval from the 
FAA. This approval may address either no action, if the current 
configuration eliminates the unsafe condition, or different actions 
necessary to address the unsafe condition described in this AD. Such 
a request should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated in the body of this AD, unless 
ready accomplished.
    To prevent the main landing gear (MLG) by forward lower edge 
wing skin structure from cracking, which, if not detected and 
corrected, could cause failure of the wing structure and loss of 
control of the airplane, accomplish the following:
    (a) Upon accumulating 4,000 hours time-in-service (TIS) or 
within the next 200 hours TIS after the effective date of this AD, 
whichever occurs later, inspect the MLG bay forward lower edge wing 
skin structure adjacent to the main spar for cracks in accordance 
with the Accomplishment Instructions section of Jetstream Service 
Bulletin (SB) 57-A-JA920540, Original Issue September 1, 1992.
    (1) If cracks are found, prior to further flight, replace the 
existing doublers with joggled doublers of improved design in 
accordance with the Accomplishment Instructions section of Jetstream 
SB 57-A-JA920540, Original Issue September 1, 1992.
    (2) If no cracks are found, re-inspect the MLG bay forward lower 
edge wing skin structure at intervals not to exceed 600 hours TIS 
until modified as specified in paragraph (b) of this AD.
    (b) Upon accumulating 9,000 hours TIS or within the next 200 
hours TIS after the effective date of this AD, whichever occurs 
later, unless already accomplished as specified in paragraph (a)(1) 
of this AD, replace the existing doublers with joggled doublers of 
improved design in accordance 

[[Page 41870]]
with the Accomplishment Instructions section of Jetstream SB 57-A-
JA920540.
    (c) Replacing the joggled doublers as required by paragraphs 
(a)(1) or (b) of this AD eliminates the repetitive inspection 
requirements of this AD.
    (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, Brussels Aircraft 
Certification Office, FAA, Europe, Africa, and Middle East Office, 
c/o American Embassy, B-1000 Brussels, Belgium. The request shall be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Brussels Aircraft 
Certification Office.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Brussels Aircraft Certification Office.

    (f) All persons affected by this directive may obtain copies of 
the document referred to herein upon request to Jetstream Aircraft 
Limited, Prestwick International Airport, Ayrshire, KA9 2RW, 
Scotland, or Jetstream Aircraft Inc., Librarian, P.O. Box 16029, 
Dulles International Airport, Washington, D.C. 20041-6029; 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.

    Issued in Kansas City, Missouri, on August 7, 1995.
Gerald W. Pierce,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-20004 Filed 8-11-95; 8:45 am]
BILLING CODE 4910-13-M