[Federal Register Volume 62, Number 169 (Tuesday, September 2, 1997)]
[Rules and Regulations]
[Pages 46184-46186]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-23065]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-181-AD; Amendment 39-10118; AD 97-18-08]
RIN 2120-AA64
Airworthiness Directives; British Aerospace (Jetstream) Model
4101 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to certain British Aerospace (Jetstream) Model 4101
airplanes. This action requires a visual inspection to detect wear
damage of the drag brace of the main landing gear (MLG), and
replacement of any worn parts with new or serviceable parts. This
action also requires an inspection to determine whether there is
movement in the spherical bearing of the lower link of the drag brace,
certain measurements of the drag brace, and repetitive inspections, if
necessary. This amendment is prompted by reports of loose spherical
bearings in the links of the drag brace of the MLG. The actions
specified in this AD are intended to prevent reduced structural
integrity and potential collapse of the
[[Page 46185]]
MLG due to loose spherical bearings and subsequent wear damage of the
links of the drag brace.
DATES: Effective September 17, 1997.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of September 17, 1997.
Comments for inclusion in the Rules Docket must be received on or
before November 3, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 97-NM-181-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The service information referenced in this AD may be obtained from
AI(R) American Support, Inc., 13850 Mclearen Road, Herndon, Virginia
20171. This information may be examined at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the
Office of the Federal Register, 800 North Capitol Street, NW., suite
700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Mark Quam, Aerospace Engineer, ANM-
113, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056; telephone (425) 227-2145; fax (425) 227-
1149.
SUPPLEMENTARY INFORMATION: 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 British Aerospace
(Jetstream) Model 4101 airplanes. The CAA advises that it has received
reports of loose spherical bearings in the lower link of the drag brace
of the main landing gear (MLG). The loosened spherical bearings have
been attributed to improper swaging on some landing gear units. Such
loosened spherical bearings and subsequent wear damage of the links of
the drag brace, if not detected and corrected, could result in reduced
structural integrity and potential collapse of the MLG.
Explanation of Relevant Service Information
British Aerospace has issued Jetstream Alert Service Bulletin J41-
A32-061, dated July 11, 1997, which describes procedures for performing
a visual inspection to detect wear damage of the drag brace of the
left-and right-hand MLG, and replacement of any worn part with a new or
serviceable part. The alert service bulletin also describes procedures
to detect any movement of the spherical bearing and to measure the
lower link to the upper link and the lower link to the strut attachment
of the drag brace, and repetitive inspections, if necessary.
Additionally APPH Ltd. has issued APPH Service Bulletin AIR84352-
32-05, dated June 1997, which describes procedures for an inspection to
detect movement of the spherical bearings installed in the lower links
of the drag braces of the MLG, and rework, if necessary. The CAA has
approved APPH Service Bulletin AIR84352-32-05, and has classified
Jetstream Alert Service Bulletin J41-A32-061 as mandatory, and issued
British airworthiness directive 003-07-97, dated July 25, 1997, in
order to assure the continued airworthiness of these airplanes in the
United Kingdom.
FAA's Conclusions
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.
Explanation of Requirements of Rule
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, this AD is being issued to prevent reduced
structural integrity and potential collapse of the MLG due to loose
spherical bearings in the links of the drag brace, which could result
in wear damage to the drag brace of the MLG. This AD requires a visual
inspection to detect wear damage of the drag brace of the MLG, and
replacement of any worn parts with new or serviceable parts. This AD
also requires an inspection to determine whether there is movement in
the spherical bearing of the lower link of the drag brace, certain
measurements of the drag brace, and repetitive inspections, if
necessary. The actions are required to be accomplished in accordance
with the Jetstream alert service bulletin described previously.
Determination of Rule's Effective Date
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the 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
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 97-NM-181-AD.'' The postcard will be date stamped and
returned to the commenter.
Regulatory Impact
The regulations adopted herein will 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 final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to
[[Page 46186]]
correct an unsafe condition in aircraft, and that it is not a
``significant regulatory action'' under Executive Order 12866. It has
been determined further that this action involves an emergency
regulation under DOT Regulatory Policies and Procedures (44 FR 11034,
February 26, 1979). If it is determined that this emergency regulation
otherwise would be significant under DOT Regulatory Policies and
Procedures, a final regulatory evaluation will be prepared and placed
in the Rules Docket. A copy of it, if filed, may be obtained from the
Rules Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
97-18-08 British Aerospace Regional Aircraft [Formerly Jetstream
Aircraft Limited, British Aerospace (Commercial Aircraft) Limited]:
Amendment 39-10118. Docket 97-NM-181-AD.
Applicability: Jetstream Model 4101 airplanes, constructors
numbers 41004 through 41100 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 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 as indicated, unless accomplished
previously.
To prevent reduced structural integrity and potential collapse
of the main landing gear (MLG) due to loose spherical bearings of
the drag brace, accomplish the following:
(a) For all airplanes: Within 30 days after the effective date
of this AD, perform a visual inspection to detect wear damage of the
drag brace of the left- and right-hand MLG, in accordance with
Jetstream Alert Service Bulletin J41-A32-061, dated July 11, 1997.
(1) For airplanes on which no wear damage has been detected and
that have accumulated 8,000 or more total landings as of the
effective date of this AD or on which APPH Service Bulletin
AIR84352-32-05 has been accomplished: Prior to further flight,
perform an inspection to detect movement of the spherical bearing of
the drag brace and measure the area between the lower link and the
strut, in accordance with the Jetstream alert service bulletin.
(i) If no movement of the spherical bearing is detected and the
measurement of the area between the lower link and the strut is
within the limits specified by the service bulletin, no further
action is required by this AD.
Note 2: For the purposes of this AD, ``flight day'' is defined
as any day on which the airplane is flown.
(ii) If any movement is detected or the measurement of the area
between the lower link and the strut is beyond the limits specified
by the service bulletin, repeat the inspections required by
paragraph (a) of this AD prior to the first flight of the day for
the next 100 flight days of the airplane.
(2) For all other airplanes on which no wear damage has been
detected: Prior to further flight, perform an inspection to detect
movement of the spherical bearing of the drag brace and measure the
area between the lower link and the strut, in accordance with the
service bulletin.
(i) If no movement of the spherical bearing is detected, and the
measurement of the area between the lower link and the strut is
within the limits specified by the service bulletin, repeat the
inspections required by paragraph (a) of this AD at the time
specified in paragraph (a)(2)(i)(A) or (a)(2)(i)(B) of this AD, as
applicable.
(A) For drag braces that have accumulated less than 501 total
landings: Repeat the inspections at intervals not to exceed 100
flights until the drag brace has accumulated 500 total landings.
(B) For drag braces that have accumulated more than 500 total
landings, but less than 8,000 total landings: Repeat the inspections
at intervals not to exceed 1,000 flights.
(ii) If any movement is detected or the measurement of the area
between the lower link and the strut is beyond the limits specified
by the service bulletin, repeat the inspections required by
paragraph (a) of this AD prior to the first flight of the day for
the next 100 flight days of the airplane.
(b) For all airplanes: If any wear damage of the drag brace is
detected during any inspections required by this AD, prior to
further flight, remove the wear damaged part(s) and replace with a
new or serviceable part, in accordance with Jetstream Alert Service
Bulletin J41-A32-061, dated July 11, 1997. Within 30 days after the
replacement of a wear damaged part with a new or serviceable part,
perform the requirements of paragraph (a) of this AD.
(c) Accomplishment of APPH Service Bulletin AIR84352-32-05,
dated June 1997, constitutes terminating action for the repetitive
inspection requirements of paragraph (a)(2) of this AD.
(d) 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.
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 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(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) The actions shall be done in accordance with Jetstream Alert
Service Bulletin J41-A32-061, dated July 11, 1997. This
incorporation by reference was approved by the Director of the
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part
51. Copies may be obtained from AI(R) American Support, Inc., 13850
Mclearen Road, Herndon, Virginia 20171. Copies may be inspected at
the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW.,
Renton, Washington; or at the Office of the Federal Register, 800
North Capitol Street, NW., suite 700, Washington, DC.
(g) This amendment becomes effective on September 17, 1997.
Issued in Renton, Washington, on August 25, 1997.
Gary L. Killion,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-23065 Filed 8-29-97; 8:45 am]
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