[Federal Register Volume 59, Number 48 (Friday, March 11, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-5405]


[[Page Unknown]]

[Federal Register: March 11, 1994]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 93-NM-223-AD; Amendment 39-8849; AD 93-25-10]

 

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 document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 93-25-10 that was sent previously 
to all known U.S. owners and operators of certain Jetstream Model 4101 
airplanes by individual letters. This AD requires inspections to detect 
damage of the bearings in the aileron quadrants, replacement of damaged 
bearings with new bearings, and adjustment to the secondary stops. This 
amendment is prompted by a report that an in-flight failure of a 
bearing in a quadrant in the pilot's aileron control system caused 
abnormal backlash of the pilot's aileron control. The actions specified 
by this AD are intended to prevent reduced controllability of the 
airplane.

DATES: Effective March 28, 1994, to all persons except those persons to 
whom it was made immediately effective by priority letter AD 93-25-10, 
issued on December 16, 1993, 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 March 28, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before May 10, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 93-NM-223-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 December 16, 1993, the FAA issued 
priority letter AD 93-25-10, which is applicable to certain Jetstream 
Model 4101 airplanes. That action was prompted by a report indicating 
that an in-flight failure of a bearing in a quadrant in the pilot's 
aileron control system had caused abnormal backlash of the pilot's 
aileron control. In this incident, the co-pilot assumed control and 
landed the airplane. A subsequent fleet inspection revealed damage to 
two other bearings. This condition, if not corrected, could result in 
reduced controllability of the airplane.
    Jetstream Aircraft Limited has issued Alert Service Bulletin J41-A-
27-026, Revision 1, dated December 7, 1993, that describes procedures 
for performing repetitive detailed visual inspections to detect damage 
of the bearings in the aileron quadrants, replacing damaged bearings 
with new bearings, and adjusting the secondary stops. The Civil 
Aviation Authority (CAA), which is the airworthiness authority for the 
United Kingdom, classified this alert 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 Sec. 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 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 93-25-10 to require 
repetitive detailed visual inspections to detect damage of the bearings 
in the aileron quadrants, replacement of damaged bearings with new 
bearings, and adjustment to the secondary stops. 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 December 16, 1993, to all known U.S. owners and operators of 
certain Jetstream Model 4101 airplanes. These conditions still exist, 
and the AD is hereby published in the Federal Register as an amendment 
to Sec. 39.13 of part 39 of the Federal Aviation Regulations (FAR) to 
make it effective as to all persons.

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 93-NM-223-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:

93-25-10 Jetstream Aircraft Limited: Amendment 39-8849. Docket 93-
NM-223-AD.

    Applicability: Model 4101 airplanes, having constructor numbers 
41004 and subsequent, certificated in any category. -
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent reduced controllability of the airplane, accomplish 
the following:
    (a) Within 7 days after the effective date of this AD, perform a 
detailed visual inspection to detect damage of the bearings in the 
aileron quadrant in the pilot's and co-pilot's aileron control, in 
accordance with Jetstream Aircraft Limited Alert Service Bulletin 
J41-A-27-026, Revision 1, dated December 7, 1993.
    (1) If no damaged bearing is found, repeat the inspection, 
thereafter, at intervals not to exceed 7 days.
    (2) If any damaged bearing is found, prior to further flight, 
replace the damaged bearing with a new bearing in accordance with 
the service bulletin, and repeat the inspection, thereafter, at 
intervals not to exceed 7 days.
    (b) Within 7 days after the effective date of this AD, adjust 
the aileron secondary stop in the pilot's and co-pilot's aileron 
control system in accordance with Jetstream Aircraft Limited Alert 
Service Bulletin J41-A-27-026, Revision 1, dated December 7, 1993.
    (c) Within 7 days after the effective date of this AD, revise 
the Abnormal Procedures Section of the FAA-approved Airplane Flight 
Manual (AFM) to include the following. This may be accomplished by 
inserting a copy of this AD in the AFM.
    ``Where abnormal aileron control backlash is experienced by one 
pilot, the other pilot should assume control of the aircraft without 
using the disconnect facility. The disconnect facility should only 
be used in accordance with published procedures in cases of control 
restrictions or jamming.''
    (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, 
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: 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 
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.
    (f) The inspections, replacement, and adjustment shall be done 
in accordance with Jetstream Aircraft Limited Alert Service Bulletin 
J41-A-27-026, Revision 1, dated December 7, 1993. 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. 
-
    (g) This amendment becomes effective on March 28, 1994, to all 
persons except those persons to whom it was made immediately 
effective by priority letter AD 93-25-10, issued on December 16, 
1993, which contained the requirements of this amendment.

    Issued in Renton, Washington, on March 3, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-5405 Filed 3-10-94; 8:45 am]
BILLING CODE 4910-13-U