[Federal Register Volume 60, Number 112 (Monday, June 12, 1995)]
[Proposed Rules]
[Pages 30796-30798]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-14319]
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[[Page 30797]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 94-NM-242-AD]
Airworthiness Directives; Jetstream Model ATP Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain Jetstream Model ATP
airplanes. This proposal would require an inspection to ensure that
various components of the retraction actuator of the nose landing gear
(NLG) are secure, and an inspection of the bearing cap mounting holes
for correct hole and thread length. The proposed AD would also require
a later inspection for certain discrepancies of the retraction
actuator; installation of revised tolerance bushings; and correction of
any discrepancy found. This proposal is prompted by reports of failure
of the attachment bolts of the bearing cap of the retraction actuator
of the NLG. The actions specified by the proposed AD are intended to
prevent the inability to raise or lower the NLG, or possible collapse
of the NLG, due to failure of the attachment bolts of the bearing cap.
DATES: Comments must be received by July 24, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-242-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except
Federal holidays.
The service information referenced in the proposed rule may be
obtained from Jetstream Aircraft, Inc., P.O. Box 16029, Dulles
International Airport, Washington, DC 20041-6029. This information may
be examined at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: William Schroeder, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-2148; fax (206) 227-1149.
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 shall 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 summarizing 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 Number 94-NM-242-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, Transport Airplane Directorate, ANM-103, Attention: Rules
Docket No. 94-NM-242-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The Civil Aviation Authority (CAA), which is the airworthiness
authority for the United Kingdom, recently notified the FAA that an
unsafe condition may exist on certain Jetstream Model ATP airplanes.
The CAA advises that there have been reports indicating that the
attachment bolts of the bearing cap of the retraction actuator of the
nose landing gear (NLG) have failed. This has been determined to be the
result of mismatches between the bearing cap and bush, or inadequate
counterboring of the bearing cap. This condition, if not corrected,
could result in the inability to raise or lower the NLG, or possible
collapse of the NLG.
Jetstream has issued Service Bulletin ATP-53-30-10372A, dated
November 3, 1994, which describes procedures for an inspection to
ensure that the bearing caps, bolts, and special washers are secure.
The service bulletin also describes procedures for inspecting the
bearing cap mounting holes for correct hole and thread length.
Additionally, the service bulletin describes a later inspection for
discrepancies of the retraction actuator; installation of revised
tolerance bushings; and alignment of the outboard support bracket, if
necessary. The service bulletin also describes corrective actions for
any discrepancy that is found during the inspections. The CAA
classified this service bulletin as mandatory in order to assure the
continued airworthiness of these airplanes in the United Kingdom.
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. 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 on other airplanes of the same type design registered
in the United States, the proposed AD would require, first, an
inspection to ensure that the bearing caps, bolts, and special washers
are secure; and inspection of the bearing cap mounting holes for
correct hole and thread length. The proposed AD also would require a
later inspection for discrepancies of the retraction actuator;
installation of revised tolerance bushings; and alignment of the
outboard support bracket, if necessary. This proposed AD would require
corrective actions for any discrepancy found. The actions would be
required to be accomplished in accordance with the Jetstream Service
Bulletin ATP-76-16, dated October 14, 1994, described previously.
Unlike the procedures recommended in that Jetstream service
bulletin, however, this proposed rule would not permit further flight
after detection of any cable that is found with one wire broken in any
strand. Instead, this proposed rule would require, prior to further
flight, repair of the cable in accordance with the service bulletin.
The FAA finds that an adequate level of safety for the affected fleet
requires that damaged cables must be replaced prior to further flight.
The FAA has [[Page 30798]] determined that, in cases where certain
known unsafe conditions exist, and where actions to detect and correct
that unsafe condition can be readily accomplished, those actions must
be required.
As a result of recent communications with the Air Transport
Association (ATA) of America, the FAA has learned that, in general,
some operators may misunderstand the legal effect of AD's on airplanes
that are identified in the applicability provision of the AD, but that
have been altered or repaired in the area addressed by the AD. The FAA
points out that all airplanes identified in the applicability provision
of an AD are legally subject to the AD. If an airplane has been altered
or repaired in the affected area in such a way as to affect compliance
with the AD, the owner or operator is required to obtain FAA approval
for an alternative method of compliance with the AD, in accordance with
the paragraph of each AD that provides for such approvals. A note has
been included in this notice to clarify this long-standing requirement.
The FAA estimates that 10 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 17 work
hours per airplane to accomplish the proposed actions, and that the
average labor rate is $60 per work hour. Required parts would be
provided by the manufacturer at no cost to the operator. Based on these
figures, the total cost impact of the proposed AD on U.S. operators is
estimated to be $10,200, or $1,020 per airplane.
The total cost impact figure discussed above is based on
assumptions that no operator has yet accomplished any of the proposed
requirements of this AD action, and that no operator would accomplish
those actions in the future if this AD were not adopted.
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 proposed
regulation (1) is not a ``significant regulatory action'' under
Executive Order 12866; (2) is not a ``significant rule'' under the 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 is contained 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. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Jetstream Aircraft Limited (Formerly, British Aerospace Commercial
Aircraft Limited): Docket 94-NM-242-AD.
Applicability: Model ATP airplanes, constructor's numbers 2002
through 2056 inclusive, 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 (c) 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, unless accomplished
previously.
To prevent the inability to raise or lower the nose landing gear
(NLG), or a possible collapse of the NLG, accomplish the following:
(a) Within 300 hours time-in-service or 90 days after the
effective date of this AD, whichever occurs first: Perform an
inspection to ensure that the components of the bracket attachment
assembly of the retraction actuator of the NLG are secure, and to
ensure that the inboard and outboard support brackets of the
mounting holes of the bearing cap have correct hole and thread
lengths, in accordance with paragraph 2.A. of the Accomplishment
Instructions of Jetstream Service Bulletin ATP-53-30-10372A, dated
November 3, 1994. If any discrepancy is found, prior to further
flight, correct the discrepancy in accordance with the service
bulletin.
(b) Within 3,000 landings, or 12 months after the effective date
of this AD, whichever occurs first: Install revised tolerance
bushings in the bearing cap/bracket attachment assemblies of the NLG
retraction actuator, test the actuator for freedom of movement, and
inspect for any discrepancy of the actuator, in accordance with
paragraph 2.B. of the Accomplishment Instructions of Jetstream
Service Bulletin ATP-53-30-10372A, dated November 3, 1994.
(1) If no discrepancy is found no further action is required by
this AD.
(2) If any discrepancy is found, prior to further flight,
correct the discrepancy in accordance with the service bulletin.
(c) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate. Operators shall submit their
requests through an appropriate FAA Principal Maintenance Inspector,
who may add comments and then send it to the Manager,
Standardization Branch, ANM-113.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(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. Issued in Renton,
Washington, on June 6, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-14319 Filed 6-9-95; 8:45 am]
BILLING CODE 4910-13-U
