AD Amdt-39-10125

final rule

Airworthiness Directives; Saab Model SAAB 2000 Series Airplanes

AD Number
Amdt-39-10125
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 96-NM-229-AD
FR Citation
62 FR 47930

Applicability

TypeManufacturerModelDetails
aircraft Saab 2000 Airworthiness Directives; Saab Model SAAB 2000 Series Airplanes

Unsafe Condition

The ignition exciter in the auxiliary power unit (APU) may fail to start after flight in cold soak conditions, leading to inability to restart engines if both engines quit operating during flight.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Replace the ignition exciter in the APU with a part designed to operate better in cold weather.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

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Affected Aircraft

Saab Model SAAB 2000 series airplanes subject to the AD

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB 2000 series airplanes. This amendment requires replacement of the ignition exciter in the auxiliary power unit (APU) with a part that is designed to operate better in cold weather. This amendment is prompted by two occurrences of the APU failing to start after flight in cold soak conditions. The actions specified by this AD are intended to prevent such APU failure, which could result in the inability of the APU to restart the engines in the event both engines quit operating during flight.

Document Text

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[Federal Register Volume 62, Number 177 (Friday, September 12, 1997)]
[Rules and Regulations]
[Pages 47930-47931]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 97-23859]



[[Page 47930]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-229-AD; Amendment 39-10125; AD 97-19-05]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB 2000 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Saab Model SAAB 2000 series airplanes. This 
amendment requires replacement of the ignition exciter in the auxiliary 
power unit (APU) with a part that is designed to operate better in cold 
weather. This amendment is prompted by two occurrences of the APU 
failing to start after flight in cold soak conditions. The actions 
specified by this AD are intended to prevent such APU failure, which 
could result in the inability of the APU to restart the engines in the 
event both engines quit operating during flight.

DATES: Effective October 17, 1997.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 17, 1997.

ADDRESSES: 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 
Federal Aviation Administration (FAA), Transport Airplane Directorate, 
Rules Docket, 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: Ruth Harder, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1721; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain Saab Model SAAB 2000 
series airplanes was published in the Federal Register on May 8, 1997 
(62 FR 25151). That action proposed to require replacement of the 
ignition exciter in the auxiliary power unit with a part that is 
designed to operate better in cold weather.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the single comment received.
    The commenter supports the proposed rule.

Conclusion

    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule as proposed.

Cost Impact

    The FAA estimates that 3 Saab Model SAAB 2000 series airplanes of 
U.S. registry will be affected by this AD, that it will take 
approximately 1 work hour per airplane to accomplish the required 
replacement, and that the average labor rate is $60 per work hour. 
Required parts will be provided by the manufacturer at no cost to 
operators. Based on these figures, the cost impact of the AD on U.S. 
operators is estimated to be $180, or $60 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished the modification required by this AD 
action, and that no operator would accomplish this modification in the 
future if this AD were not adopted.

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:

97-19-05  SAAB Aircraft AB: Amendment 39-10125. Docket 96-NM-229-AD.

    Applicability: Model SAAB 2000 series airplanes, equipped with 
an auxiliary power unit (APU) having part number 4500090, serial 
numbers SP-E941224, and SP-E941228 through SP-E951259 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 
otherwise 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 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 auxiliary power unit (APU) failure, which could 
result in the inability of the APU to restart the engines in the 
event both engines quit operating during flight, accomplish the 
following:
    (a) Within 60 days after the effective date of this AD: Replace 
the ignition exciter, part number 4950787, with an ignition exciter 
having part number 179420-2, in accordance with Saab Service 
Bulletin 2000-49-005, dated December 19, 1995, including Attachment 
1, dated November 30, 1995.
    (b) As of the effective date of this AD, no person shall install 
an ignition exciter having part number 4950787 on any airplane.
    (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, Standardization Branch, ANM-113, 
FAA, Transport Airplane Directorate. Operators shall submit their 
requests through an

[[Page 47931]]

appropriate FAA Principal Maintenance Inspector, who may add 
comments and then send it to the Manager, Standardization Branch, 
ANM-113.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (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.
    (e) The modification shall be done in accordance with Saab 
Service Bulletin 2000-49-005, dated December 19, 1995, including 
Attachment 1, dated November 30, 995. 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.
    (f) This amendment becomes effective on October 17, 1997.

    Issued in Renton, Washington, on September 3, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aricraft Certification 
Service.
[FR Doc. 97-23859 Filed 9-11-97; 8:45 am]
BILLING CODE 4910-13-U

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