[Federal Register Volume 65, Number 139 (Wednesday, July 19, 2000)]
[Rules and Regulations]
[Pages 44670-44672]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-18039]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-335-AD; Amendment 39-11810; AD 2000-14-01]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 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 series airplanes, that requires 
replacement of any brake system accumulator that has aluminum end caps 
with an accumulator that has stainless steel end caps. This

[[Page 44671]]

amendment is prompted by reports of fractures of aluminum end caps on 
brake system accumulators. The actions specified by this AD are 
intended to prevent high-velocity separation of a brake system 
accumulator barrel, piston, or end cap, which could result in injury to 
personnel in the wheel well area, loss of cabin pressurization, loss of 
certain hydraulic systems, or damage to the fuel line of the auxiliary 
power unit.

DATES: Effective August 23, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 23, 2000.

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: Don Kurle, Aerospace Engineer, Systems 
and Equipment Branch, ANM-130S, FAA, Transport Airplane Directorate, 
Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-2798; 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 series 
airplanes was published in the Federal Register on January 5, 2000 (65 
FR 401). That action proposed to require replacement of any brake 
system accumulator that has aluminum end caps with an accumulator that 
has stainless steel end caps.

Comments

    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 Proposed Rule

    One commenter supports the proposed rule.

Request to Reference Corresponding Supplier Part Numbers in Spares 
Paragraph

    One commenter, the airplane manufacturer, requests that the FAA 
revise paragraph (b) of the proposed rule (the ``Spares'' paragraph) to 
reference the supplier's part numbers for the brake system accumulator 
that correspond to the airplane manufacturer's part numbers listed in 
paragraph (b) of the proposed rule. The commenter states that including 
the supplier's part numbers in this AD will assist operators in 
identifying affected parts. The FAA concurs with the commenter's 
request, and has revised paragraph (b) of this final rule to reference 
the applicable supplier's part numbers that correspond to the airplane 
manufacturer's part numbers.

Request To Extend Compliance Time

    Three commenters request that the FAA extend the compliance time 
for the actions in paragraph (a) of the proposed rule. The FAA proposed 
a compliance time of 3,000 flight hours after the effective date of 
this AD. The commenters' suggestions for extending the compliance time 
range from 10 months to 2 years or 6,000 flight hours. One commenter's 
justification for its request is the number of affected airplanes 
(estimated at 70 airplanes), the lead-time for modification kits 
(estimated at 10 months), and the lead-time for new parts (estimated at 
4 months). Another commenter notes that the lead-time for new 
accumulators or modifications parts is 90 days for the initial 
production order; however, it will take two years to produce the 
quantity of new accumulators or modifications kits that will be 
necessary to accomplish the proposed replacement throughout the fleet. 
Another commenter states that the proposed actions are appropriate for 
accomplishment in a hangar environment and, with the proposed 
compliance time of 3,000 flight hours, special maintenance visits would 
be necessary to accomplish the proposed actions within that compliance 
time. That commenter suggests that a compliance time of 18 months would 
allow the proposed actions to be accomplished at a ``C''-check for most 
affected airplanes.
    The FAA concurs that the compliance time for accomplishment of the 
replacement described in this AD may be extended somewhat, and that 
accomplishment of the required actions during a ``C''-check is 
appropriate. In developing an appropriate compliance time for this AD, 
the FAA considered not only the degree of urgency associated with 
addressing the subject unsafe condition, but the availability of 
required parts and the normal intervals for operators' ``C''-checks (as 
stated in Maintenance Review Board documents). The FAA has determined 
that 6,000 flight hours represents an appropriate interval of time 
wherein an ample number of required parts will be available for 
modification of the U.S. fleet, and wherein operators will be able to 
accomplish the replacement during a ``C''-check. The FAA also finds 
that such a compliance time will not adversely affect the safety of the 
affected airplanes. Paragraph (a) of this final rule has been revised 
accordingly.

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 changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    There are approximately 1,217 Model 747 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 324 
airplanes of U.S. registry will be affected by this AD, that it will 
take approximately 1 work hour per accumulator (airplanes may have 
three, four, or five accumulators of various types) to accomplish the 
required actions, and that the average labor rate is $60 per work hour. 
Required parts will cost approximately between $7,650 and $13,418 per 
airplane (depending on the number and type of affected accumulators). 
Based on these figures, the cost impact of the AD on U.S. operators is 
estimated to be between $7,830 and $13,718 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 a substantial direct 
effect 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, it is determined that this final rule does not have 
federalism implications under Executive Order 13132.
    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

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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:

2000-14-01  Boeing: Amendment 39-11810. Docket 99-NM-335-AD.
    Applicability: Model 747 series airplanes; as listed in Boeing 
Special Attention Service Bulletin 747-32-2461, dated August 19, 
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 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 high velocity separation of a brake system 
accumulator barrel, piston, or end cap; which could result in injury 
to personnel in the wheel well area, loss of cabin pressurization, 
loss of certain hydraulic systems, or damage to the fuel line of the 
auxiliary power unit; accomplish the following:

Replacement

    (a) At the next ``C''-check, not to exceed 6,000 flight hours 
after the effective date of this AD, replace any brake system 
accumulator that has aluminum end caps with an accumulator that has 
stainless steel end caps in accordance with Boeing Special 
AttentionService Bulletin 747-32-2461, dated August 19, 1999.

Spares

    (b) As of the effective date of this AD, no person shall install 
a brake system accumulator having part number (P/N) BACA11E1 (Parker 
P/N 2660472-1 or 2660472M1) or BACA11E5 (Parker P/N 2660472-5 or 
2660472M5) on any airplane.

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, Seattle Aircraft Certification 
Office (ACO), 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, 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.

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.

Incorporation by Reference

    (e) The actions shall be done in accordance with Boeing Special 
Attention Service Bulletin 747-32-2461, dated August 19, 1999. 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.

Effective Date

    (f) This amendment becomes effective on August 23, 2000.

    Issued in Renton, Washington, on July 11, 2000.
Donald L. Riggin,
Acting Manager,, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-18039 Filed 7-18-00; 8:45 am]
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