[Federal Register Volume 59, Number 72 (Thursday, April 14, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-8684]


[[Page Unknown]]

[Federal Register: April 14, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-34-AD; Amendment 39-8880; AD 94-08-08]

 

Airworthiness Directives; Jetstream Aircraft Limited 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 Jetstream Model 4101 airplanes. This action 
requires installation of fusible trunnion pins in the shock struts and 
drag braces of the main landing gear (MLG). This amendment is prompted 
by a report of incorrectly manufactured trunnion pins that may cause 
the MLG to compromise the structural integrity of the wing fuel tanks. 
The actions specified in this AD are intended to prevent damage to the 
wing fuel tanks and the resultant fuel spillage and fire hazard when 
the maximum intended design load limits are exceeded during landing.

DATES: Effective April 29, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 29, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before June 13, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-34-AD, 1601 Lind Avenue SW., Renton, 
Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
Jetstream Aircraft, Incorporated, 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; telephone (206) 227-2148; fax 
(206) 227-1320.

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 certain Jetstream Model 
4101 airplanes. The CAA advises that certain trunnion pins in the shock 
struts and drag braces of the main landing gear (MLG) were manufactured 
incorrectly. The trunnion pins in these airplanes were designed to be 
fusible so that the MLG would break away from the airplane when landing 
loads exceed the intended design limits, such as those that may be 
encountered during emergency landing. However, the defective trunnion 
pins were not manufactured with this fusible characteristic. Therefore, 
these defective trunnion pins may cause the MLG to fail to break away 
from the airplane and, consequently, may compromise the structural 
integrity of the wing fuel tank. This condition, if not corrected, 
could result in damage to the wing fuel tanks and the resultant fuel 
spillage and fire hazard when the maximum intended design load limits 
are exceeded during landing.
    Jetstream has issued Service Bulletin J41-32-017, dated February 7, 
1994, that describes procedures for installation of new fusible 
trunnion pins in the shock struts and drag braces of the MLG. 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 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, this AD is being issued to prevent damage to the 
wing fuel tanks and the resultant fuel spillage and fire hazard. This 
AD requires installation of new trunnion pins in the shock struts and 
drag braces of the MLG. The actions are required to be accomplished in 
accordance with the service bulletin described previously.
    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 notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 94-NM-34-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 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 14 CFR part 
39 of the Federal Aviation Regulations 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:

94-08-08 Jetstream Aircraft Limited: Amendment 39-8880. Docket 94-
NM-34-AD.

    Applicability: Model 4101 airplanes having constructors numbers 
41004 through 41027 inclusive; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent damage to the wing fuel tanks and the resultant fuel 
spillage and fire hazard when the maximum intended design load 
limits are exceeded during landing, accomplish the following:
    (a) Within 300 hours time-in-service after the effective date of 
this AD, install new trunnion pins in the shock struts and drag 
braces of the main landing gear in accordance with Jetstream Service 
Bulletin J41-32-017, dated February 7, 1994.
    (b) As of the effective date of this AD, no person shall install 
any shock strut assembly having part number AIR83072-8, or drag 
brace assembly having part number AIR84352-2, on any airplane.
    (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. 
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: 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 
Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the 
airplane to a location where the requirements of this AD can be 
accomplished.
    (e) The installation shall be done in accordance with Jetstream 
Service Bulletin J41-32-017, dated February 7, 1994. 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, Incorporated, 
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.
    (f) This amendment becomes effective on April 29, 1994.

    Issued in Renton, Washington, on April 6, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-8684 Filed 4-13-94; 8:45 am]
BILLING CODE 4910-13-U