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[Federal Register Volume 60, Number 103 (Tuesday, May 30, 1995)]
[Rules and Regulations]
[Pages 28035-28037]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-12711]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-NM-74-AD; Amendment 39-9241; AD 95-09-03]

Airworthiness Directives; Jetstream Model 4101 Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 95-09-03, that was sent 
previously to all known U.S. owners and operators of Jetstream Model 
4101 airplanes by individual letters. This AD requires inspection to 
determine the number of hours time-in-service on the landing gear 
control unit, and modification of the cable (electrical wiring circuit) 
of the landing gear control unit. This amendment is prompted by a 
report of failure of a micro-switch in the landing gear control unit. 
The actions specified by this AD are intended to prevent uncommanded 
retraction of a landing gear, which could adversely affect airplane 
controllability.

DATES: Effective June 14, 1995, to all persons except those persons to 
whom it was made immediately effective by priority letter AD 95-09-03, 
issued on April 18, 1995, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 14, 1995.
    Comments for inclusion in the Rules Docket must be received on or 
before July 31, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-74-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The applicable service information 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; or at the Office of the Federal Register, 800 North Capitol 
Street, NW., suite 700, Washington, DC.

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) 227-1320.

SUPPLEMENTARY INFORMATION: On April 18, 1995, the FAA issued priority 
letter AD 95-09-03, which is applicable to Jetstream Model 4101 
airplanes. That action was prompted by a report of failure of a micro-
switch in the landing gear control unit. This failure was apparently 
due to a manufacturing defect. Investigation revealed that the micro-
switch failure caused the units to [[Page 28036]] produce spurious 
signals, which resulted in an uncommanded retraction of the landing 
gear while the airplane was on the ground. This condition, if not 
corrected, could result in uncommanded retraction of a landing gear, 
which could adversely affect airplane controllability.
    Jetstream has issued Alert Service Bulletin J41-A32-042, dated 
April 13, 1995, which describes procedures for inspection to determine 
the number of hours time-in-service on the landing gear control unit. 
This alert service bulletin also describes procedures for a 
modification of the cable (electrical wiring circuit) of the landing 
gear control unit, which will preclude uncommanded retraction of a 
landing gear in the event of a micro-switch failure. The Civil Aviation 
Authority (CAA), which is the airworthiness authority for the United 
Kingdom, classified this service bulletin as mandatory.
    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 the unsafe condition described is likely to exist or develop 
on other airplanes of the same type design registered in the United 
States, the FAA issued priority letter AD 95-09-03 to require 
inspection to determine the number of hours time-in-service on the 
landing gear control unit, and modification of the cable (electrical 
wiring circuit) of the landing gear control unit. The actions are 
required to be accomplished in accordance with the alert service 
bulletin previously described.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual letters 
issued on April 18, 1995 to all known U.S. owners and operators of 
Jetstream Model 4101 airplanes. These conditions still exist, and the 
AD is hereby published in the Federal Register as an amendment to 
section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to 
make it effective as to all persons.
    This is considered interim action. The manufacturer has advised 
that it currently is developing a modification that will further 
address the unsafe condition addressed by this AD. Once this 
modification is developed, approved, and available, the FAA may 
consider additional rulemaking.
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 95-NM-74-AD.'' The postcard will be date stamped and 
returned to the commenter.
    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 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. 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:

95-09-03  Jetstream Aircraft Limited: Amendment 39-9241. Docket 95-
NM-74-AD.

    Applicability: Model 4101 airplanes, constructor numbers 41001 
through 41046 inclusive, and 41048 through 41052 inclusive; having 
either landing gear control unit part number 717701-1 or 717701 
modification A; 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 (b) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different [[Page 28037]] 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 uncommanded retraction of the landing gear, which can 
adversely affect airplane controllability, accomplish the following:
    (a) Within 8 hours time-in-service after the effective date of 
this AD, perform an inspection to determine the number of hours 
time-in-service on the landing gear control unit, in accordance with 
Jetstream Alert Service Bulletin J41-A32-042, dated April 13, 1995.
    (1) For those airplanes on which the control unit has 
accumulated less than 200 hours time-in-service: Prior to further 
flight, modify the cable (electrical wiring circuit) of the landing 
gear control unit in accordance with the alert service bulletin.
    (2) For those airplanes on which the control unit has 
accumulated 200 hours or more time-in-service: Within 50 hours time-
in-service or within 7 days after the effective date of this AD, 
whichever occurs earlier, modify the cable (electrical wiring 
circuit) of the landing gear control unit in accordance with the 
alert service bulletin.
    (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, 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.
    (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 inspection and modification shall be done in accordance 
with Jetstream Alert Service Bulletin J41-A32-042, dated April 13, 
1995. 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 Jetstream Aircraft, Inc., P.O. 
Box 16029, Dulles International Airport, Washington, DC 20041-6029. 
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.
    (e) This amendment becomes effective on June 14, 1995, to all 
persons except those persons to whom it was made immediately 
effective by priority letter AD 95-09-03, issued April 18, 1995, 
which contained the requirements of this amendment.

    Issued in Renton, Washington, on May 18, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-12711 Filed 5-26-95; 8:45 am]
BILLING CODE 4910-13-U
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