[Federal Register Volume 63, Number 245 (Tuesday, December 22, 1998)]
[Rules and Regulations]
[Pages 70641-70643]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-33689]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-75-AD; Amendment 39-10960; AD 98-26-17]
RIN 2120-AA64


Airworthiness Directives; British Aerospace Jetstream Model 3201 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to all British Aerospace Jetstream Model 3201 airplanes. This 
AD requires accomplishing both a routine visual inspection and either a 
detailed visual inspection or x-ray inspection of the main landing gear 
(MLG) bay auxiliary spar booms for cracks or fuel leaks on both the 
left and right sides of the airplane. This AD also requires obtaining 
and incorporating repair procedures for the MLG bay auxiliary spar 
where fuel leaks or cracks are found. This AD is the result of 
mandatory continuing airworthiness information (MCAI) issued by the 
airworthiness authority for the United Kingdom. The actions specified 
by this

[[Page 70642]]

AD are intended to prevent wing failure caused by cracks or fuel leaks 
in the area of the MLG bay auxiliary spar booms, which could result in 
loss of control of the airplane.

DATES: Effective February 5, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of February 5, 1999.

ADDRESSES: Service information that applies to this AD may be obtained 
from British Aerospace Regional Aircraft, Prestwick International 
Airport, Ayrshire, KA9 2RW, Scotland; telephone: (01292) 479888; 
facsimile: (01292) 479703. This information may also be examined at the 
Federal Aviation Administration (FAA), Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 98-CE-75-AD, Room 1558, 
601 E. 12th Street, Kansas City, Missouri 64106; or at the Office of 
the Federal Register, 800 North Capitol Street, NW, suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. S.M. Nagarajan, Aerospace 
Engineer, FAA, Small Airplane Directorate, 1201 Walnut, suite 900, 
Kansas City, Missouri 64106; telephone: (816) 426-6932; facsimile: 
(816) 426-2169.

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to all British Aerospace 
Jetstream Model 3201 airplanes was published in the Federal Register as 
a notice of proposed rulemaking (NPRM) on October 13, 1998 (63 FR 
54635). The NPRM proposed to require accomplishing both a routine 
visual inspection and either a detailed visual inspection or x-ray 
inspection of the MLG bay auxiliary spar booms for cracks or fuel leaks 
on both the left and right sides of the airplane. The NPRM proposed to 
also require obtaining and incorporating repair procedures for the MLG 
bay auxiliary spar where fuel leaks or cracks are found. Accomplishment 
of the proposed actions as specified in the NPRM would be required in 
accordance with British Aerospace Jetstream Alert Service Bulletin 57-
A-JA 980441, ORIGINAL ISSUE: April 28, 1998, REVISION NO. 1: July 7, 
1998.
    The NPRM was the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for the United 
Kingdom.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of the rule as proposed except for 
minor editorial corrections. The FAA has determined that these minor 
corrections will not change the meaning of the AD and will not add any 
additional burden upon the public than was already proposed.

Compliance Time of This AD

    Although the cracks on the MLG bay auxiliary spar booms could occur 
as a result of repetitive airplane operation, the FAA believes that the 
residual stresses in the component are originating from a manufacturing 
fault during the machining/heat treatment stages. The cracks could 
exist, but not be noticed, after just a few hours of airplane 
operation. The stress incurred during flight operations or temperature 
changes could then cause rapid crack growth. In order to assure that 
even very small cracks in the MLG bay auxiliary spar booms do not go 
undetected, the FAA is utilizing a compliance based on calendar time.

Cost Impact

    The FAA estimates that 124 airplanes in the U.S. registry will be 
affected by this AD.
    Accomplishing the routine visual inspection required in this AD 
will take approximately 1 workhour per airplane, at an average labor 
rate of approximately $60 an hour. Based on these figures, the total 
cost impact of the routine visual inspection on U.S. operators is 
estimated to be $7,440, or $60 per airplane.
    Accomplishing the detailed visual inspection required in this AD 
will take approximately 16 workhours per airplane, at an average labor 
rate of $60 per hour. Accomplishing the x-ray inspection required in 
this AD will take approximately 12 workhours per airplane, at an 
average labor rate of approximately $60 an hour. Based on these 
figures, the total cost impact of the detailed inspection on U.S. 
operators is estimated to be $119,040, or $960 per airplane, and 
$89,280, or $720 per airplane for the x-ray inspection.
    These figures only take into account the costs of inspections and 
do not take into account the costs for repairing any MLG bay auxiliary 
spar boom where fuel leaks or cracks are found during the inspections.

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.
    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 copy of the final evaluation prepared for this 
action is contained in the Rules Docket. A copy of it may be obtained 
by contacting 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 a new airworthiness directive 
(AD) to read as follows:

98-26-17  British Aerospace: Amendment 39-10960; Docket No. 98-CE-
75-AD.

    Applicability: Jetstream Model 3201 airplanes, all serial 
numbers, 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

[[Page 70643]]

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 (d) 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 in the body of this AD, unless 
already accomplished.
    To prevent wing failure caused by cracks or fuel leaks in the 
area of the main landing gear (MLG) bay auxiliary spar booms, which 
could result in loss of control of the airplane, accomplish the 
following:
    (a) Within the next 45 calendar days after the effective date of 
this AD, accomplish the following:
    (1) Perform a routine visual inspection of the MLG bay auxiliary 
spar booms for cracks or fuel leaks on both the left and right sides 
of the airplane. Accomplish this inspection in accordance with Part 
1 of the Accomplishment Instructions section of British Aerospace 
Jetstream Alert Service Bulletin 57-A-JA 980441, Original Issue: 
April 28, 1998, Revision No. 1: July 7, 1998.
    (2) Perform either a detailed visual inspection or x-ray 
inspection of the MLG bay auxiliary spar booms for cracks or fuel 
leaks on both the left and right sides of the airplane. Accomplish 
this inspection in accordance with Part 2 of the Accomplishment 
Instructions section of British Aerospace Jetstream Alert Service 
Bulletin 57-A-JA 980441, Original Issue: April 28, 1998, Revision 
No. 1: July 7, 1998.
    (b) If cracks or leaks are found during any inspection required 
by paragraphs (a)(1) and (a)(2) of this AD, prior to further flight, 
accomplish the following:
    (1) Obtain repair instructions from the manufacturer through the 
FAA, Small Airplane Directorate, at the address specified in 
paragraph (d) of this AD; and
    (2) Incorporate these repair instructions.
    (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) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Small Airplane Directorate, Aircraft 
Certification Service, 1201 Walnut, suite 900, Kansas City, Missouri 
64106. The request shall be forwarded through an appropriate FAA 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Small Airplane Directorate.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.

    (e) Questions or technical information related to British 
Aerospace Jetstream Alert Service Bulletin 57-A-JA 980441, Original 
Issue: April 28, 1998, Revision No. 1: July 7, 1998, should be 
directed to British Aerospace Regional Aircraft, Prestwick 
International Airport, Ayrshire, KA9 2RW, Scotland; telephone: 
(01292) 479888; facsimile: (01292) 479703. This service information 
may be examined at the FAA, Central Region, Office of the Regional 
Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.
    (f) The inspections required by this AD shall be done in 
accordance with British Aerospace Jetstream Alert Service Bulletin 
57-A-JA 980441, Original Issue: April 28, 1998, Revision No. 1: July 
7, 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 British Aerospace 
Regional Aircraft, Prestwick International Airport, Ayrshire, KA9 
2RW, Scotland. Copies may be inspected at the FAA, Central Region, 
Office of the Regional Counsel, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri, 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 British AD 001-
04-98, dated May 7, 1998.

    (g) This amendment becomes effective on February 5, 1999.

    Issued in Kansas City, Missouri, on December 15, 1998.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 98-33689 Filed 12-21-98; 8:45 am]
BILLING CODE 4910-13-P