[Federal Register Volume 59, Number 223 (Monday, November 21, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-27966]


[[Page Unknown]]

[Federal Register: November 21, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-125-AD; Amendment 39-9071; AD 94-23-08]

 

Airworthiness Directives; Jetstream Model HS 748 Series 2A and 2B 
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), 
applicable to all Jetstream Model HS 748 Series 2A and 2B airplanes. 
This action requires repetitive replacement of the structurally 
significant items (SSI) on the nose landing gear (NLG) and main landing 
gear (MLG) with serviceable SSI's. This amendment is prompted by 
fatigue testing which revealed that the SSI's on the NLG and the MLG 
have a limited service life. The actions specified in this AD are 
intended to ensure the replacement of the SSI's that have reached the 
maximum life limit; SSI's that are not replaced could fail and lead to 
the failure of the NLG and MLG during taxi, take-off, or landing.

DATES Effective: December 6, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of December 6, 1994.
    Comments for inclusion in the Rules Docket must be received on or 
before January 20, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-125-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
Dowty Aerospace, Customer Support Center, P.O. Box 49, Sterling, 
Virginia 20166. 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) 227-2141; fax (206) 227-1100.

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 all Jetstream Model HS 
748 series 2A and 2B airplanes. The CAA advises that results of fatigue 
testing, conducting by Dowty [the manufacturer of the nose landing gear 
(NLG) and main landing gear (MLG) components], revealed that certain 
components in the NLG and MLG specified as structurally significant 
items (SSI) have a limited service life. Investigation revealed that 
these SSI's, upon attaining or exceeding a certain number of landings, 
can fail due to fatigue-related stress. If not replaced in a timely 
manner, the SSI's could fail and lead to the failure of the NLG and MLG 
during taxi, take-off, or landing.
    Dowty has issued Service Bulletin 32-104E, dated January 20, 1993, 
which describes procedures for determining the number of landings 
accumulated on the SSI's on the NLG and MLG, and repetitively replacing 
these SSI's with serviceable SSI's at regulator intervals. The CAA 
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 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 ensure the replacement 
of the SSI's that have reached the maximum life limit. This AD requires 
initially determining the number of landings accumulated on the SSI's 
currently installed in the NLG and MLG, and repetitively replacing the 
SSI's with serviceable SSI's, upon the accumulation of a certain number 
of landings. The actions would be required to be accomplished in 
accordance with the service bulletin described previously.
    There currently are no Jetstream Model HS 748 series 2A and 2B 
airplanes on the U.S. Register. All airplanes included in the 
applicability of this rule currently are operated by non-U.S. operators 
under foreign registry; therefore, they are not directly affected by 
this AD action. However, the FAA considers that this rule is necessary 
to ensure that the unsafe condition is addressed in the event that any 
of these subject airplanes are imported and placed on the U.S. Register 
in the future.
    Should an affected airplane be imported and placed on the U.S. 
Register in the future, it would require approximately 40 work hours to 
accomplish the required actions, at an average labor charge of $60 per 
work hour. Based on these figures, the total cost impact of this AD 
would be $2,400 per airplane, per replacement cycle.
    Since this AD action does not affect any airplane that is currently 
on the U.S. register, it has no adverse economic impact and imposes no 
additional burden on any person. Therefore, notice and public 
procedures hereon are unnecessary and the amendment may be made 
effective in less than 30 days after publication in the Federal 
Register.

Comments Invited

    Although this action is in the form of a final rule and was not 
preceded by notice and 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 94-NM-125-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.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) will not have a 
significant economic impact, positive or negative, on a substantial 
number of small entities under the criteria of the Regulatory 
Flexibility Act. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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:

94-23-08  Jetstream Aircraft Limited (Formerly British Aerospace 
Commercial Aircraft, Limited): Amendment 39-9071. Docket 94-NM-125-
AD.

    Applicability: All Model Jetstream Model HS 748 series 2A and 2B 
airplanes, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To ensure replacement of the SSI's that have reached the maximum 
life limit, accomplish the following:
    (a) Within 60 days after the effective date of this AD, 
determine the number of landings accumulated on each structurally 
significant item (SSI) currently installed in the nose landing gear 
(NLG) and main landing gear (MLG), in accordance with Dowty 
Aerospace Landing Gear Service Bulletin 32-104E, dated January 20, 
1993.
    (1) If the number of landings accumulated on an SSI is equal to 
or greater than the number of landings specified in the ``Life 
Limitations'' column of the applicable table in the service 
bulletin, prior to further flight, replace the SSI with a 
serviceable SSI, in accordance with the service bulletin. 
Thereafter, replace the SSI at intervals not to exceed the 
accumulation of the number of landings specified in the ``Life 
Limitations'' column of the applicable table in the service 
bulletin.
    (2) If the number of landings accumulated on the SSI is less 
than the number of landings specified in the ``Life Limitations'' 
column of the applicable table in the service bulletin, replace the 
SSI with a serviceable SSI prior to or upon the accumulation of the 
number of landings specified in the ``Life Limitations'' column of 
the applicable table in the service bulletin. Thereafter, replace 
the SSI at intervals not to exceed the accumulation of the number of 
landings specified in the ``Life Limitations'' column of the 
applicable table in the 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.

    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.

    (c) Special flight permits may be issued in accordance with 
sections Secs. 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 replacement shall be done in accordance with Dowty 
Aerospace Landing Gear Service Bulletin 32-104E, dated January 20, 
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 Dowty Aerospace, Customer 
Support Center, P.O. Box 49, Sterling, Virginia 20166. 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 December 6, 1994.

    Issued in Renton, Washington, on November 7, 1994.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-27966 Filed 11-18-94; 8:45 am]
BILLING CODE 4910-13-U