[Federal Register Volume 65, Number 152 (Monday, August 7, 2000)]
[Rules and Regulations]
[Pages 48144-48146]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-19670]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-88-AD; Amendment 39-11748; AD 2000-10-23]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, -200, -300, 
747SR, and 747SP Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; correction.

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SUMMARY: This document corrects information in an existing 
airworthiness directive (AD) that applies to certain Boeing Model 747-
100, -200, -300, 747SR, and 747SP series airplanes. That AD currently 
requires repetitive inspections to detect cracking of the longeron 
splice fittings at stringer 11, on the left and right sides at body 
station 2598, and replacement of any cracked fitting with a new 
fitting. This document clarifies the applicable compliance time for 
certain airplanes. This correction is necessary to ensure that fatigue 
cracking on longeron splice fittings, which could result in reduced 
controllability of the horizontal stabilizer, is detected and corrected 
in a timely manner.

DATES: Effective June 30, 2000.
    The incorporation by reference of Boeing Service Bulletin 747-
53A2410, Revision 3, including Addendum, dated March 12, 1998, as 
listed in the regulations, was approved previously by the Director of 
the Federal Register as of June 30, 2000 (65 FR 34061, May 26, 2000).
    The incorporation by reference of Boeing Alert Service Bulletin 
747-53A2410, Revision 2, including Addendum, dated October 30, 1997, as 
listed in the regulations, was approved previously by the Director of 
the Federal Register as of January 13, 1998 (62 FR 67550, December 29, 
1997).

FOR FURTHER INFORMATION CONTACT: Rick Kawaguchi, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-1153; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: On May 18, 2000, the Federal Aviation 
Administration (FAA) issued AD 2000-10-23, amendment 39-11748 (65 FR 
34061, May 26, 2000), which applies to certain Boeing Model 747-100, -
200, -300, 747SR, and 747SP series airplanes. That AD requires 
repetitive inspections to detect cracking of the longeron splice 
fittings at stringer 11, on the left and right sides at body station 
2598, and replacement of any cracked fitting with a new fitting. That 
AD was prompted by reports that fatigue cracking was found on longeron 
splice fittings. The actions required by that AD are intended to detect 
and correct such fatigue cracking, which could result in reduced 
controllability of the horizontal stabilizer.

Need for the Correction

    Since the issuance of AD 2000-10-23, the manufacturer has informed 
the FAA that the correct compliance time for certain airplanes is 
unclear. Paragraph (a)(1) of the AD states the applicable compliance 
time, ``For airplanes that have accumulated fewer than 17,000 total 
flight cycles or 63,000 total flight hours as of the effective date of 
this AD.'' Paragraph (a)(2) of the AD states the applicable compliance 
time, ``For airplanes that have accumulated 17,000 total flight cycles 
or more, or 63,000 total flight hours or more, as of the effective date 
of this AD.'' The manufacturer points out that the use of the word 
``or'' (``* * * fewer than 17,000 total flight cycles or 63,000 total 
flight hours * * *'') in paragraph (a)(1) makes it possible that some 
airplanes may inadvertently be subject to the compliance times in both 
paragraphs (a)(1) and (a)(2).
    The FAA has reviewed this wording and determined that a correction 
to AD 2000-10-23 is necessary. The FAA's intent is that the compliance 
times in paragraph (a)(1) apply to airplanes with

[[Page 48145]]

relatively fewer flight cycles. That is, as of the effective date of 
this AD, if an airplane's total number of flight cycles is less than 
17,000, and the same airplane's total number of flight hours is less 
than 63,000, then the compliance times in paragraph (a)(1) apply. 
Therefore, this correction will revise paragraph (a)(1) to state that 
the compliance time in that paragraph applies to ``airplanes that have 
accumulated fewer than 17,000 total flight cycles and 63,000 total 
flight hours as of the effective date of this AD.''

Correction of Publication

    This document corrects the error and correctly adds the AD as an 
amendment to Sec. 39.13 of the Federal Aviation Regulations (14 CFR 
39.13).
    The AD is reprinted in its entirety for the convenience of affected 
operators. The effective date of the AD remains June 30, 2000.
    Since this action only corrects and clarifies a current 
requirement, it has no adverse economic impact and imposes no 
additional burden on any person. Therefore, the FAA has determined that 
notice and public procedures are unnecessary.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Correction

    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  [Corrected]

    2. Section 39.13 is amended by correctly adding the following 
airworthiness directive (AD):

2000-10-23  Boeing: Amendment 39-11748. Docket 97-NM-88-AD.
    Applicability: Model 747-100, 747-200, 747-300, 747SR, and 747SP 
series airplanes; having line positions 201 through 886 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 and correct fatigue cracking of the longeron splice 
fittings at stringer 11, which could result in reduced 
controllability of the horizontal stabilizer, accomplish the 
following:

Initial Inspection

    (a) Perform a one-time detailed visual inspection to detect 
cracking of the longeron fittings at stringer 11, on the left and 
right sides at body station 2598, at the time specified in paragraph 
(a)(1) or (a)(2) of this AD, as applicable, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2410, Revision 2, dated October 30, 1997, including Addendum; or 
Boeing Service Bulletin 747-53A2410, Revision 3, dated March 12, 
1998, including Addendum. After the effective date of this AD, only 
Revision 3 shall be used.
    (1) For airplanes that have accumulated fewer than 17,000 total 
flight cycles and 63,000 total flight hours as of the effective date 
of this AD: Inspect at the later of the times specified in paragraph 
(a)(1)(i) or (a)(1)(ii) of this AD.
    (i) Prior to the accumulation of 17,000 total flight cycles or 
63,000 total flight hours, whichever occurs first.
    (ii) Within 1,800 flight cycles or 7,000 flight hours after the 
effective date of this AD, whichever occurs first.
    (2) For airplanes that have accumulated 17,000 total flight 
cycles or more, or 63,000 total flight hours or more, as of the 
effective date of this AD: Inspect at the earlier of the times 
specified in paragraphs (a)(2)(i) and (a)(2)(ii) of this AD.
    (i) Prior to the accumulation of 22,000 total flight cycles or 
78,000 total flight hours, whichever occurs first.
    (ii) Within 1,800 flight cycles or 7,000 flight hours after the 
effective date of this AD, whichever occurs first.

    Note 2: Where there are differences between the AD and the 
service bulletin, the AD prevails.


    Note 3: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or 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.''

Repetitive Inspections

    (b) If no crack is found during the inspection required by 
paragraph (a) of this AD, repeat the inspection one time at the 
later of the times specified in paragraphs (b)(1) and (b)(2) of this 
AD, and thereafter at intervals not to exceed 3,000 flight cycles or 
18,000 flight hours, whichever occurs first.
    (1) Within 3,000 flight cycles or 18,000 flight hours after 
accomplishment of the most recent inspection, whichever occurs 
first.
    (2) Within 1,800 flight cycles or 7,000 flight hours after the 
effective date of this AD, whichever occurs first.

Replacement and Repetitive Inspections

    (c) If any crack is found during any inspection required by 
paragraph (a) or (b) of this AD: Prior to further flight, replace 
the cracked fitting with a new fitting, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2410, Revision 2, dated October 30, 1997, including Addendum; or 
Boeing Service Bulletin 747-53A2410, Revision 3, dated March 12, 
1998, including Addendum. After the effective date of this AD, only 
Revision 3 shall be used. Then, repeat the inspection specified in 
paragraph (a) of this AD at the later of the times specified in 
paragraphs (c)(1) and (c)(2) of this AD, and thereafter at intervals 
not to exceed 3,000 flight cycles or 18,000 flight hours, whichever 
occurs first.
    (1) Within 17,000 flight cycles or 63,000 flight hours after 
replacement, whichever occurs first.
    (2) Within 1,800 flight cycles or 7,000 flight hours after the 
effective date of this AD, whichever occurs first.

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, 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 4: 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

    (e) Special flight permits may be issued in accordance with 
Secs. 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) The actions shall be done in accordance with Boeing Alert 
Service Bulletin 747-53A2410, Revision 2, including Addendum, dated 
October 30, 1997; or Boeing Service Bulletin 747-53A2410, Revision 
3, including Addendum, dated March 12, 1998.
    (1) The incorporation by reference of Boeing Service Bulletin 
747-53A2410, Revision 3, including Addendum, dated March 12, 1998, 
was approved previously by the Director of the Federal Register as 
of June 30, 2000 (65 FR 34061, May 26, 2000).
    (2) The incorporation by reference of Boeing Alert Service 
Bulletin 747-53A2410,

[[Page 48146]]

Revision 2, including Addendum, dated October 30, 1997, was approved 
previously by the Director of the Federal Register as of January 13, 
1998 (62 FR 67550, December 29 1997).
    (3) 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

    (g) The effective date of this amendment remains June 30, 2000.


    Issued in Renton, Washington, on July 28, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-19670 Filed 8-4-00; 8:45 am]
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