AD Amdt-39-10510

final rule

Airworthiness Directives; Boeing Model 747-400 Series Airplanes

AD Number
Amdt-39-10510
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 97-NM-138-AD
FR Citation
63 FR 24914
Technical illustration of an aircraft electrical generator and wiring assembly
Problem area Electrical system

Applicability

TypeManufacturerModelDetails
aircraft Boeing 747-400 Airworthiness Directives; Boeing Model 747-400 Series Airplanes

Unsafe Condition

Improper installation or maintenance of the auxiliary power unit (APU) battery grounds can cause overheating and heat damage, leading to smoke or fire from the APU.

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

Required Actions

Remove and reconfigure the APU battery grounds to ensure proper installation and maintenance.

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

Compliance Time

Before further flight

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

Affected Aircraft

Boeing Model 747-400 series airplanes with improperly installed or maintained APU battery grounds.

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 Boeing Model 747-400 series airplanes, that requires removal and reconfiguration of the battery grounds of the auxiliary power unit (APU). This amendment is prompted by reports of smoke or fire coming from the APU due to battery grounds that were not installed or maintained properly. The actions specified by this AD are intended to prevent overheating and heat damage of the APU battery grounds due to improper installation of the APU battery ground, which could result in heat damage and consequent smoke or fire on the airplane.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 63, Number 87 (Wednesday, May 6, 1998)]
[Rules and Regulations]
[Pages 24914-24915]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 98-11562]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-138-AD; Amendment 39-10510; AD 98-09-29]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-400 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 747-400 series airplanes, that 
requires removal and reconfiguration of the battery grounds of the 
auxiliary power unit (APU). This amendment is prompted by reports of 
smoke or fire coming from the APU due to battery grounds that were not 
installed or maintained properly. The actions specified by this AD are 
intended to prevent overheating and heat damage of the APU battery 
grounds due to improper installation of the APU battery ground, which 
could result in heat damage and consequent smoke or fire on the 
airplane.

DATES: Effective June 10, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 10, 1998.

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. 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: Forrest Keller, Senior Aerospace 
Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056; telephone (425) 227-2790; fax (425) 227-1181.

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 Boeing Model 747-400 
series airplanes was published in the Federal Register on November 25, 
1997 (62 FR 62726). That action proposed to require removal and 
reconfiguration of the battery grounds of the auxiliary power unit 
(APU).
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support for the Proposal

    One commenter supports the proposal.

Request To Extend the Compliance Time

    The Air Transport Association (ATA) of America, on behalf of one of 
its members, requests that the proposed compliance time be extended to 
allow the modification to be accomplished within 12 months, rather than 
6 months. This ATA member operates the largest number of U.S.-
registered 747-400 airplanes. The ATA member claims that such an 
extension is warranted in light of the amount of time required for 
preparation and accomplishment of the actions required by this proposed 
AD, and in light of the results of inspections to detect discrepancies 
of the APU battery grounds performed subsequent to receipt of and in 
accordance with Boeing telex M-7240-96-0927, dated May 24, 1996. The 
ATA member maintains that the results of this inspection indicated that 
the APU grounds on its airplanes that are the subject of the unsafe 
condition of this proposed AD were retorqued and found to be free of 
discrepancies.
    The FAA concurs with the commenter's request to extend the 
compliance time from 6 months to 12 months. In light of the information 
presented by the commenter, the FAA finds that such an extension will 
allow the modification to be performed with minimal effect on the 
maintenance schedule and no adverse effect on safety. Paragraph (a) of 
the final rule has been revised to specify a compliance time of 12 
months.

[[Page 24915]]

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the change previously 
described. The FAA has determined that this change will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 359 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 26 airplanes of U.S. registry 
will be affected by this AD, that it will take approximately 16 work 
hours per airplane to accomplish the required actions, and that the 
average labor rate is $60 per work hour. Required parts will cost 
approximately $1,325 per airplane. Based on these figures, the cost 
impact of the AD onU.S. operators is estimated to be $59,410, or $2,285 
per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the 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 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:

98-09-29  Boeing: Amendment 39-10510. Docket 97-NM-138-AD.

    Applicability: Model 747-400 series airplanes, as listed in 
Boeing Alert Service Bulletin 747-24A2214, dated June 19, 1997; 
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 (b) 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 the auxiliary power unit (APU) from overheat and heat 
damage due to an improperly installed/maintained APU battery ground, 
accomplish the following:
    (a) Within 12 months after the effective date of this AD, 
reconfigure the APU battery grounds to a dual-direct ground, single-
lug configuration, in accordance with Boeing Alert Service Bulletin 
747-24A2214, dated June 19, 1997.
    (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, Seattle Aircraft Certification 
Office (ACO). Operators shall submit their requests through an 
appropriate FAA Principal Maintenance Inspector, who may add 
comments and then send it to the Manager, Seattle ACO.

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

    (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) The actions shall be done in accordance with Boeing Alert 
Service Bulletin 747-24A2214, dated June 19, 1997. 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 Boeing Commercial Airplane Group, 
P.O. Box 3707, Seattle, Washington 98124-2207. 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 June 10, 1998.

    Issued in Renton, Washington, on April 24, 1998.
Gary L. Killion,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-11562 Filed 5-5-98; 8:45 am]
BILLING CODE 4910-13-U

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