[Federal Register Volume 64, Number 178 (Wednesday, September 15, 1999)]
[Rules and Regulations]
[Pages 49977-49979]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-23471]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-278-AD; Amendment 39-11316; AD 99-19-29]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767 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 767 series airplanes, that requires 
repetitive inspections of certain H-11 tension bolts at each side-of-
body kick-load fitting and on the lower splice plate (both located on 
the wing rear spar) to detect damaged or broken bolts; and follow-on 
actions, if necessary. This amendment also requires eventual 
replacement of the existing bolts with new, improved bolts, which 
constitutes terminating action for the repetitive inspections. This 
amendment is prompted by a report that an operator found two broken H-
11 tension bolts on the side-of-body kick-load fitting on one airplane. 
The actions specified by this AD are intended to prevent cracking of 
the bolts due to stress corrosion, which could result in reduced 
structural integrity of the wing-to-body joint structure.

DATES: Effective October 20, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 20, 1999.

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: James G. Rehrl, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-2783; 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 767 series 
airplanes was published in the Federal Register on November 23, 1998 
(63 FR 64657). That action proposed to require repetitive inspections 
of certain H-11 tension bolts at each side-of-body kick-load fitting 
and on the lower splice plate (both located on the wing rear spar) to 
detect damaged, broken, or improperly sealed bolts; and follow-on 
actions, if necessary. That action also proposed to require eventual 
replacement of the existing bolts with new, improved bolts, which 
constitutes terminating action for the repetitive inspections.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the four comments received.
    Two commenters support the proposed rule, and one commenter does 
not object to the proposed rule.

Editorial Changes to the Final Rule

    The FAA has determined that it is necessary to clarify the detailed 
visual inspection of paragraph (a)(1) of the requirements of this AD. 
The FAA has added the words ``of the bolts,'' to further clarify the 
inspection area. The final rule has been changed accordingly.

Request to Delete Certain Descriptive Language

    One commenter, the manufacturer, requests that the FAA delete the 
words ``improperly sealed'' from paragraphs (a) and (b) of the proposed 
AD. The commenter states that because the most significant influence of 
the H-11 bolt fracture is the presence of high pre-load, which cannot 
be determined by inspection, any anomalies in the bolt sealant will 
have no effect on the bolt fracture, unless the bolt is highly pre-
loaded. The commenter also suggests that using the condition of the H-
11 bolt sealant as a guide for bolt replacement will cause unnecessary, 
unscheduled airplane down time and confusion, as it is likely that 
improperly sealed bolts will be found. The commenter further adds that 
a clear definition of an ``improperly sealed bolt'' is not provided in 
either the Boeing Service Bulletin or the Notice of Proposed Rulemaking 
(NPRM).
    The FAA concurs with the request to delete certain descriptive 
language of the AD, as requested by the commenter. The FAA has revised 
this language throughout the final rule.

Request to Revise the Compliance Time for the Terminating Action

    One commenter requests that the FAA revise the proposed compliance 
time for the terminating action from 6,000 flight cycles to 9,000 
flight cycles. The commenter states that the issue of H-11 bolts 
fracture is more dependent on calendar time rather than flight cycles. 
This additional allowance of time would provide high cycle usage 
operators an equivalent of 48 months calendar time that is provided for 
low cycle usage operators.
    The FAA concurs with this request, and has revised paragraph (c) of 
the final rule accordingly.

Explanation of Change Made to Proposal

    The FAA has added a note to the final rule to clarify the 
definition of a detailed visual inspection.

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 177 Model 767 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 70 
airplanes of U.S. registry will be affected by this AD.
    It will take approximately 2 work hours per airplane to accomplish 
the required inspection of the kick-load fitting, at an average labor 
rate of $60 per work hour. Based on these figures, the cost impact of 
the inspection of the kick-load fitting required by this AD on U.S. 
operators is estimated to be $8,400, or $120 per airplane, per 
inspection cycle.
    It will take approximately 23 work hours per airplane to accomplish 
the required inspection of the splice plate, at an average labor rate 
of $60 per work hour. Based on these figures, the cost impact of the 
inspection of the splice plate required by this AD on U.S.

[[Page 49978]]

operators is estimated to be $96,600, or $1,380 per airplane, per 
inspection cycle.
    It will take approximately 140 work hours per airplane to 
accomplish the required replacement, at an average labor rate of $60 
per work hour. Parts will be provided by the manufacturer at no cost to 
the operators. Based on these figures, the cost impact of the 
replacement required by this AD on U.S. operators is estimated to be 
$588,000, or $8,400 per airplane.
    The cost impact figures discussed above are 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:

99-19-29  Boeing: Amendment 39-11316. Docket 98-NM-278-AD.

    Applicability: Model 767 series airplanes, line positions 1 
through 177 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 prevent cracking of the H-11 tension bolts on the side-of-
body kick-load fitting due to stress corrosion, which could result 
in reduced structural integrity of the wing-to-body joint structure, 
accomplish the following:
    (a) Within 90 days after the effective date of this AD: Perform 
a detailed visual inspection of the four H-11 tension bolts at each 
side-of-body kick-load fitting located on the wing rear spar to 
detect damaged or broken bolts; and accomplish the requirements in 
either paragraph (a)(1) or (a)(2) of this AD, in accordance with the 
Accomplishment Instructions of Boeing Service Bulletin 767-57A0064, 
Revision 1, dated July 9, 1998.
    (1) Option 1: Repeat the detailed visual inspection of the bolts 
at each side-of-body kick-load fitting thereafter at intervals not 
to exceed 90 days, until accomplishment of the actions specified in 
paragraph (c) of this AD. Or
    (2) Option 2: Perform a detailed visual inspection of the four 
H-11 tension bolts on the lower splice plate located on the wing 
rear spar to detect damaged or broken bolts. Repeat the detailed 
inspection of each side-of-body kick-load fitting and the lower 
splice plate thereafter at intervals not to exceed 18 months, until 
accomplishment of the actions specified in paragraph (c) of this AD.

    Note 2: 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.''

    (b) If evidence of any damaged or broken bolt is detected, prior 
to further flight, replace the discrepant bolt with a new, improved 
bolt in accordance with Boeing Service Bulletin 767-57A0064, 
Revision 1, dated July 9, 1998. Thereafter, repeat the detailed 
inspection in either paragraph (a)(1) or (a)(2) of this AD, as 
applicable, until accomplishment of the actions specified in 
paragraph (c) of this AD.
    (c) Within 9,000 flight cycles or 48 months after the effective 
date of this AD, whichever occurs first, replace all four H-11 
tension bolts at each side-of-body kick-load fitting with new, 
improved bolts, and perform a detailed visual inspection to detect 
any damaged or broken bolt of the lower splice plate located on the 
wing rear spar, in accordance with Boeing Service Bulletin 767-
57A0064, Revision 1, dated July 9, 1998. If any damaged or broken 
bolt is detected during the inspection, prior to further flight, 
replace the discrepant bolt with a new, improved bolt in accordance 
with Boeing Service Bulletin 767-57A0064, Revision 1, dated July 9, 
1998. Accomplishment of the actions specified in this paragraph 
constitutes terminating action for the repetitive inspection 
requirements of this AD.

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 3: 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 
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) The inspections and replacements shall be done in accordance 
with Boeing Service Bulletin 767-57A0064, Revision 1, dated July 9, 
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 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.
    (g) This amendment becomes effective on October 20, 1999.


[[Page 49979]]


    Issued in Renton, Washington, on September 2, 1999.
Dorenda D. Baker,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-23471 Filed 9-14-99; 8:45 am]
BILLING CODE 4910-13-P