[Federal Register Volume 63, Number 191 (Friday, October 2, 1998)]
[Rules and Regulations]
[Pages 52961-52963]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-26389]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-287-AD; Amendment 39-10816; AD 98-21-08]
RIN 2120-AA64
Airworthiness Directives; Saab Model SAAB 2000 Series 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 Saab Model SAAB 2000 series airplanes. This
action requires repetitive functional tests (checks) to verify proper
operation of the nose wheel steering system (NWSS) limitswitch, and
replacement of the existing limitswitch with a new limitswitch, if
necessary. This amendment is prompted by issuance of mandatory
continuing airworthiness information by a foreign civil airworthiness
authority. The actions specified in this AD are intended to prevent
combined failure of the limitswitch and the feedback shaft in the NWSS
servo unit, which could result in uncommanded nose wheel steering
deflection and reduced controllability of the airplane on the ground
during takeoff or landing.
[[Page 52962]]
DATES: Effective October 19, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of October 19, 1998.
Comments for inclusion in the Rules Docket must be received on or
before November 2, 1998.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 98-NM-287-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The service information referenced in this AD may be obtained from
Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88, Linkoping,
Sweden. 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: Norman B. Martenson, Manager,
International Branch, ANM-116, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
227-2110; fax (425) 227-1149.
SUPPLEMENTARY INFORMATION: The Luftfartsverket (LFV), which is the
airworthiness authority for Sweden, notified the FAA that an unsafe
condition may exist on certain Saab Model SAAB 2000 series airplanes.
The LFV advises that it received a report of uncommanded nose wheel
steering deflection during landing of a Saab Model SAAB 2000 series
airplane, without pilot engagement of the steering system. This
deflection was attributed to a short circuit in the nose wheel steering
system (NWSS) limitswitch, in combination with a failure of the
feedback shaft in the NWSS servo unit. The LFV also advised the FAA
that previous failures of the feedback shaft have been reported and
corrective action for the NWSS servo units is presently being
evaluated. Such combined failure of the limitswitch and the feedback
shaft could result in uncommanded nose wheel steering deflection and
reduced controllability of the airplane on the ground during takeoff or
landing.
Explanation of Relevant Service Information
Saab has issued Service Bulletin 2000-32-050, dated August 24,
1998, which describes procedures for repetitive functional tests
(checks) to verify proper operation of the NWSS limitswitch, and
replacement of the limitswitch, if necessary. The LFV classified this
service bulletin as mandatory and issued Swedish airworthiness
directive SAD 1-130, dated August 27, 1998, in order to assure the
continued airworthiness of these airplanes in Sweden.
FAA's Conclusions
This airplane model is manufactured in Sweden 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 LFV has kept the FAA informed of
the situation described above. The FAA has examined the findings of the
LFV, 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 combined
failure of the limitswitch and the feedback shaft of the NWSS, which
could result in reduced controllability of the airplane on the ground
during takeoff or landing. This AD requires accomplishment of the
actions specified in the service bulletin described previously.
Interim Action
The FAA is considering further rulemaking action to supersede this
AD to require modification of the feedback shaft in the NWSS servo
units, which will constitute terminating action for the repetitive
functional tests (checks) required by this AD action. However, the
planned compliance time for these actions is sufficiently long so that
prior notice and time for public comment will be practicable.
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 98-NM-287-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 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
[[Page 52963]]
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:
98-21-08 Saab Aircraft AB: Amendment 39-10816. Docket 98-NM-287-AD.
Applicability: Model SAAB 2000 series airplanes, serial numbers
004 through 063 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 (b) 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 combined failure of the limitswitch and the feedback
shaft in the nose wheel steering system (NWSS) servo unit, which
could result in uncommanded nose wheel steering deflection and
reduced controllability of the airplane on the ground during takeoff
or landing, accomplish the following:
(a) Within 3 weeks after the effective date of this AD, perform
a functional test (check) to verify proper operation of the NWSS
limitswitch, in accordance with Saab Service Bulletin 2000-32-050,
dated August 24, 1998.
(1) If no malfunction is detected, repeat the functional test
thereafter at intervals not to exceed 400 flight hours.
(2) If any malfunction is detected, prior to further flight,
replace the existing limitswitch with a new limitswitch in
accordance with the service bulletin. Repeat the functional test
thereafter at intervals not to exceed 400 flight hours.
(b) 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, International Branch, ANM-116, 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, International
Branch, ANM-116.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the International Branch, ANM-116.
(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) The functional tests (checks) and replacement shall be done
in accordance with Saab Service Bulletin 2000-32-050, dated August
24, 1998. 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 Saab Aircraft AB,
SAAB Aircraft Product Support, S-581.88, Linko-ping, Sweden. 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.
Note 3: The subject of this AD is addressed in Swedish
airworthiness directive SAD 1-130, dated August 27, 1998.
(e) This amendment becomes effective on October 19, 1998.
Issued in Renton, Washington, on September 28, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-26389 Filed 10-1-98; 8:45 am]
BILLING CODE 4910-13-P
