[Federal Register Volume 64, Number 140 (Thursday, July 22, 1999)]
[Rules and Regulations]
[Pages 39396-39398]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-18409]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-350-AD; Amendment 39-11232; AD 99-15-12]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB 2000 Series 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 certain Saab Model SAAB 2000 series airplanes. This 
action requires repetitive detailed inspections to detect looseness or 
gap of the press fit bushing installation of the actuator fittings of 
the aileron trim tabs, and eventual replacement of the bushings with 
new, staked bushings. Accomplishment of such replacement terminates the 
repetitive inspections. This action also provides for an optional 
temporary preventive action, which, if accomplished, would terminate 
the repetitive inspections until the terminating action is 
accomplished. This amendment is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified in this AD are intended to prevent 
looseness or gap of the bushings. In the event of failure of the 
redundant trim tab actuator, such looseness or gap of the bushings 
could lead to trim tab flutter and consequent structural failure of the 
trim tab and reduced controllability of the airplane.

DATES: Effective August 6, 1999.

    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 6, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before August 23, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-350-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.

    The service information referenced in this AD 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; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

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:

Discussion

    The Luftfartsverket (LFV), which is the airworthiness authority for 
Sweden, notified the FAA that an unsafe condition may exist on certain 
Saab Model SAAB 2000 series airplanes. The LFV advises that a failure 
of a bushing of the flap support fitting occurred during a fatigue 
test. The bushing installation of the flap support fitting is similar 
to the bushing installation of the actuator fittings of the aileron 
trim tabs. In the event of failure of the redundant trim tab actuator, 
such a failure of the bushing could lead to trim tab flutter and 
consequent structural failure of the trim tab and reduced 
controllability of the airplane.

Explanation of Relevant Service Information

    Saab has issued Service Bulletin 2000-57-011, dated October 1, 
1998, which describes procedures for repetitive visual inspections to 
detect looseness or gap of the press fit bushing installation of the 
actuation fittings of the aileron trim tabs. In addition, the service 
bulletin describes procedures for eventual replacement of existing 
bushings with new, staked bushings in the fittings. Such replacement 
when accomplished, eliminates the need for the repetitive inspections. 
The service bulletin also describes procedures for an optional 
temporary preventive action that involves the installation of washers 
on the bushings of the actuator fittings of the aileron trim tabs. 
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) No. 1-132, dated October 8, 1998, 
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 21.19) 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 the 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, this AD is being issued to prevent looseness or 
gap of the press fit bushing installation of the actuator fittings of 
the aileron trim tabs. This AD requires accomplishment of the actions 
specified in the service bulletin described previously, except as 
discussed below.

Differences Between this AD and Service Bulletin

    Operators should note that, although the service bulletin specifies 
that the manufacturer may be contacted for disposition of a certain 
repair condition, this AD requires the repair of that condition to be 
accomplished in accordance with a method approved by the FAA, or the 
LFV (or its delegated agent).

Cost Impact

    None of the airplanes affected by this action are 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.

[[Page 39397]]

    Should an affected airplane be imported and placed on the U.S. 
Register in the future, it would require approximately 3 work hours to 
accomplish the required inspection, at an average labor rate of $60 per 
work hour. Based on these figures, the cost impact of the inspection 
would be $180 per airplane, per inspection cycle.
    It would require approximately 12 work hours for the bushing 
replacement, at an average labor rate of $60 per work hour. Required 
parts would be provided by the manufacturer at no cost to the operator. 
Based on these figures, the cost impact of the installation would be 
$720 per airplane.
    Should an operator elect to accomplish the optional temporary 
preventive action, it would take approximately 8 work hours to 
accomplish it, at an average labor rate of $60 per work hour. Required 
parts would be provided by the manufacturer at no cost to the operator. 
Based on these figures, the cost impact of the optional temporary 
preventive action would be $480 per airplane.

Determination of Rule's Effective Date

    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, prior 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 98-NM-350-AD.'' The postcard will be date stamped and 
returned to the commenter.

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 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. 106(g), 40113, 44701.

Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

99-15-12 Saab Aircraft AB: Amendment 39-11232. Docket 98-NM-350-AD.

    Applicability: Model SAAB 2000 series airplanes having serial 
numbers -004 through -011 inclusive and -013 through -016 inclusive, 
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 (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, unless accomplished 
previously.
    To detect looseness or gap of the press fit bushing installation 
of the actuation fittings of the aileron trim tabs, which, in the 
event of failure of the redundant trim tab actuator, could lead to 
trim tab flutter and consequent structural failure of the trim tab, 
accomplish the following:

Inspection

    (a) Within 400 flight hours after the effective date of this AD, 
perform a detailed inspection of the bushing installation of the 
actuator fittings of the aileron trim tabs to detect looseness or 
gap, in accordance with Saab Service Bulletin 2000-57-011, dated 
October 1, 1998.
    (1) If no looseness or gap is found, repeat the inspection 
thereafter at intervals not to exceed 800 flight hours until the 
requirements of paragraph (b) of this AD have been accomplished. 
Accomplishment of the temporary preventive action specified in 
paragraph 2.C. of the Accomplishment Instructions of the service 
bulletin terminates the repetitive inspections until the 
requirements of paragraph (b) of this AD have been accomplished.
    (2) Except as specified in paragraph (c) of this AD, if any 
looseness or gap is found, prior to further flight, accomplish the 
corrective actions specified in paragraph 2.G. of the Accomplishment 
Instructions of the service bulletin. Repeat the inspection 
thereafter at intervals not to exceed 800 flight hours until the 
requirements of paragraph (b) of this AD have been accomplished. 
Accomplishment of the temporary preventive action specified in 
paragraph 2.C. of the Accomplishment Instructions of the service 
bulletin terminates the repetitive inspections of paragraph (a) of 
this AD.

    Note 2: For the purposes of this AD, a detailed inspection is 
defined as: ``An intensive visual examination of a specific 
structural area, system, installation, or

[[Page 39398]]

assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good 
lighting at intensity deemed appropriate by the inspector. 
Inspection aids such as mirror, magnifying lenses, etc. may be used. 
Surface cleaning and elaborate access procedures may be required.''

Terminating Action

    (b) Except as specified in paragraph (c) of this AD, within 
6,000 flight hours after the effective date of this AD, replace the 
existing bushings with new, staked bushings in the actuator fittings 
of the aileron trim tabs in accordance with Saab Service Bulletin 
2000-57-011, dated October 1, 1998. Accomplishment of this 
replacement terminates the requirements of this AD.

Conditional Corrective Action

    (c) If, during the accomplishment of the bushing installation 
inspection required by paragraph (a)(2) or the bushing replacement 
required by paragraph (b) of this AD, any radial play is detected 
between the small diameter flanged bushing and the fitting lug hole, 
and the radial play is 0.006 inch or less, prior to further flight, 
repair it in accordance with a method approved by the Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
or the Luftfartsverket (LFV) (or its delegated agent).

Alternative Methods of Compliance

    (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, International Branch, ANM-116. 
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 3: 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

    (e) 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.

Incorporation by Reference

    (f) Except as provided in paragraph (c) of this AD, the actions 
shall be done in accordance with Saab Service Bulletin 2000-57-011, 
dated October 1, 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 Saab Aircraft 
AB, SAAB Aircraft Product Support, S-581.88, Linkoping, Sweden. 
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.

    Note 4: The subject of this AD is addressed in Swedish 
airworthiness directive (SAD) 1-132, dated October 8, 1998.
    (g) This amendment becomes effective on August 6, 1999.

    Issued in Renton, Washington, on July 14, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-18409 Filed 7-21-99; 8:45 am]
BILLING CODE 4910-13-P