[Federal Register Volume 64, Number 184 (Thursday, September 23, 1999)]
[Proposed Rules]
[Pages 51486-51488]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-24848]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-197-AD]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB 2000 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Saab Model SAAB 2000 
series airplanes. This proposal would require modification of the 
airplane by coldworking fastener holes at the front and rear wing spars 
and by installing modified support angles for the lower trailing edge 
panel of the wing. This proposal is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified by the proposed AD are intended to 
prevent fatigue cracking in the lower spar cap of the wing rear spar 
and in the lower skin at the wing front spar, just outside the nacelle, 
on the left-hand and right-hand side of the airplane, which could 
result in fuel leakage and consequent fire in or around the wing.

DATES: Comments must be received by October 25, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-197-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Saab Aircraft AB, SAAB Aircraft Product Support, S-
581.88, Linkoping, Sweden. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact

[[Page 51487]]

concerned with the substance of this proposal 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 99-NM-197-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 99-NM-197-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Luftfartsverket (LFV), which is the airworthiness authority for 
Sweden, recently notified the FAA that an unsafe condition may exist on 
certain Saab Model SAAB 2000 series airplanes. The LFV advises that, 
during full-scale fatigue testing of the airplane, cracks were detected 
at some fastener holes in the lower spar cap of the wing rear spar and 
in the lower skin at the wing front spar, just outside the nacelle, on 
the left-hand and right-hand sides of the airplane. This condition, if 
not corrected, could result in fuel leakage and consequent fire in or 
around the wing.

Explanation of Relevant Service Information

    Saab has issued Service Bulletin 2000-57-029, dated June 4, 1999, 
which describes procedures for modification of the airplane by 
coldworking fastener holes at the front and rear wing spars and by 
installing modified support angles for the lower trailing edge panel of 
the wing. The modification also involves nondestructive test (NDT) and 
detailed visual inspections of holes for discrepancies, and repairs, if 
necessary. Accomplishment of the actions specified in the service 
bulletin is intended to adequately address the identified unsafe 
condition. The LFV classified this service bulletin as mandatory and 
issued Swedish airworthiness directive SAD 1-142, dated June 4, 1999, 
in order to assure the continued airworthiness of these airplanes in 
Sweden.

FAA's Conclusions

    This airplane model is manufactured in Sweden 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 LFV has kept the FAA informed of 
the situation described above. The FAA has examined the findings of the 
LFV, 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.

Explanation of Requirements of Proposed Rule

    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, the proposed AD would require accomplishment of 
the actions specified in the service bulletin described previously, 
except as discussed below.

Differences Between Proposed Rule and Service Bulletin

    Operators should note that, although the service bulletin specifies 
that the manufacturer may be contacted for repair instructions for 
certain damage conditions, this proposal would require the repair of 
those conditions to be accomplished in accordance with a method 
approved by either the FAA, or the LFV (or its delegated agent). In 
light of the type of repair that would be required to address the 
identified unsafe condition, and in consonance with existing bilateral 
airworthiness agreements, the FAA has determined that, for this 
proposed AD, a repair approved by either the FAA or the LFV would be 
acceptable for compliance with this proposed AD.

Cost Impact

    The FAA estimates that 3 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 180 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. The manufacturer states that 
necessary parts would be provided at no cost to operators. Based on 
these figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $32,400, or $10,800 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 draft 
regulatory 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, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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 the following new 
airworthiness directive:

Saab Aircraft AB: Docket 99-NM-197-AD.

    Applicability: Model SAAB 2000 series airplanes, as listed in 
Saab Service Bulletin 2000-57-029, dated June 4, 1999; 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 request approval for an 
alternative method of compliance in accordance with paragraph (c) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or

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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, unless accomplished 
previously.
    To prevent fatigue cracking in the lower spar cap of the wing 
rear spar and in the lower skin at the wing front spar, just outside 
the nacelle, on the left-hand and right-hand side of the airplane, 
which could result in fuel leakage and consequent fire in or around 
the wing, accomplish the following:
    (a) Prior to the accumulation of 13,000 total flight cycles, or 
within 500 flight cycles after the effective date of this AD, 
whichever occurs later, modify the airplane by coldworking the 
fastener holes at the front and rear wing spar (including all 
applicable nondestructive test and detailed visual inspections and 
repairs of holes) and installing modified support angles for the 
lower trailing edge panel of the wing, in accordance with the 
instructions of Saab Service Bulletin SAAB 2000-57-029, dated June 
4, 1999.
    (b) Where Saab Service Bulletin 2000-57-029, dated June 4, 1999, 
specifies that Saab be contacted for repair instructions for certain 
damage conditions, this AD requires that such damage conditions must 
be repaired in accordance with a method approved by either the 
Manager, International Branch, ANM-116, FAA, Transport Airplane 
Directorate; or the Luftfartsverket (LFV) (or its delegated agent). 
For a repair method to be approved by the Manager, International 
Branch, ANM-116, as required by this paragraph, the Manager's 
approval letter must specifically reference this AD.

Alternative Methods of Compliance

    (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, International Branch, ANM-116, 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, International 
Branch, ANM-116.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (d) 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.

    Note 3: The subject of this AD is addressed in Swedish 
airworthiness directive SAD 1-142, dated June 4, 1999.

    Issued in Renton, Washington, on September 17, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-24848 Filed 9-22-99; 8:45 am]
BILLING CODE 4910-13-P