[Federal Register Volume 65, Number 2 (Tuesday, January 4, 2000)]
[Proposed Rules]
[Pages 250-251]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-50]


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 Proposed Rules
                                                 Federal Register
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
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  Federal Register / Vol. 65, No. 2 / Tuesday, January 4, 2000 / 
Proposed Rules  

[[Page 250]]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-346-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 777 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Boeing 777 series 
airplanes. This proposal would require a one-time inspection to detect 
cracking of the fastener holes common to the upper wing skins and 
trailing edge panels of both wings, and corrective actions, if 
necessary. This proposal also would require coldwork of the fastener 
holes and installation of new or serviceable fasteners. This proposal 
is prompted by a report indicating that fatigue cracks have been found 
in the upper wing skin of both wings. The actions specified by the 
proposed AD are intended to prevent fatigue cracking of the upper wing 
skin, which could result in reduced structural integrity of the wing.

DATES: Comments must be received by February 18, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-346-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Stan Wood, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 227-2772; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-346-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 99-NM-346-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report indicating that fatigue cracks have 
been found in the upper wing skin of both wings on a Boeing Model 777 
test airplane. During fatigue testing of the airplane, two cracks were 
detected at 80,813 flight cycles. Both cracks were detected at the tab 
out for the outboard support fitting of the main landing gear beam. The 
crack found on the left upper wing skin was 1.5 inches in length, and 
the crack found in the right upper wing skin was 5.1 inches in length. 
Examination of the cracked parts was inconclusive as to when the cracks 
had initiated. Such fatigue cracking, if not detected and corrected, 
could result in reduced structural integrity of the wing.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
777-57A0022, dated August 26, 1999, which describes procedures for a 
one-time eddy current inspection to detect cracking of the fastener 
holes common to the upper wing skins and trailing edge panels of both 
wings, and corrective actions, if necessary. The corrective actions 
involve rework and re-inspection of the fastener hole. Additionally, 
for any fastener hole that may require rework and re-inspections, the 
corrective actions also involve measurement of the fastener hole 
diameter and edge margin to ensure specific limits are maintained. The 
alert service bulletin also describes procedures for coldwork of the 
fastener holes and installation of new or serviceable fasteners. 
Accomplishment of the actions specified in the alert service bulletin 
is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require accomplishment of the actions specified in 
the alert service bulletin described previously, except as discussed 
below.

Differences Between Proposed Rule and Alert Service Bulletin

    Operators should note that, although the alert service bulletin 
specifies that the manufacturer may be contacted for disposition of 
certain conditions, this proposal would require the repair of those 
conditions to be accomplished in

[[Page 251]]

accordance with a method approved by the FAA.

Cost Impact

    There are approximately 82 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 33 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
13 work hours per airplane to accomplish the proposed actions, and that 
the average labor rate is $60 per work hour. Required parts would cost 
approximately $216 per airplane. Based on these figures, the cost 
impact of the proposed AD on U.S. operators is estimated to be $32,868, 
or $996 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed 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 proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:

Boeing: Docket 99-NM-346-AD.

    Applicability: Model 777 series airplanes having line numbers 1 
through 119 inclusive, except line numbers 94, 102, 104, and 118, 
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 fatigue cracking of the upper wing skin, which could 
result in reduced structural integrity of the wing, accomplish the 
following:

Eddy Current Inspection of Fastener Holes

    (a) Prior to the accumulation of 16,000 total flight cycles or 
40,000 total flight hours, whichever occurs earlier, perform a one-
time eddy current inspection to detect cracking of the fastener 
holes common to the upper wing skins and trailing edge panels of 
both wings, in accordance with Boeing Alert Service Bulletin 777-
57A0022, dated August 26, 1999.

Rework and Re-Inspection of Fastener Hole

    (b) If any cracking is detected during the inspection required 
by paragraph (a) of this AD, prior to further flight, oversize the 
fastener hole and perform additional eddy current inspections to 
detect cracking of the fastener holes until all cracking is no 
longer detectable by means of eddy current inspection. Perform the 
actions in accordance with Boeing Alert Service Bulletin 777-
57A0022, dated August 26, 1999. Prior to further flight, oversize 
the fastener hole an additional \1/32\-inch minimum and measure the 
starting hole diameter and edge margin of the fastener hole, in 
accordance with the alert service bulletin.
    (1) If the fastener hole diameter or the edge margin of any 
fastener hole is not within the limits specified in the alert 
service bulletin, prior to further flight, repair in accordance with 
a method approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA, Transport Airplane Directorate, or a Boeing 
Company Designated Engineering Representative who has been 
authorized by the FAA to make such findings. For a repair method to 
be approved by the Manager, Seattle ACO, as required by this 
paragraph, the Manager's approval letter must specifically reference 
this AD.
    (2) If the fastener hole diameter and edge margin of all the 
fastener holes are within the limits specified in the alert service 
bulletin, prior to further flight, accomplish the requirements of 
paragraph (c) of this AD.

Coldwork of Fastener Holes

    (c) If no cracking is detected during the eddy current 
inspection required by paragraph (a), or the fastener hole diameter 
and edge margin of all the fastener holes are within the limits 
required by paragraph (b) of this AD, prior to further flight, 
coldwork the fastener holes and install new or serviceable 
fasteners, in accordance with Boeing Alert Service Bulletin 777-
57A0022, dated August 26, 1999.

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 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.

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.

    Issued in Renton, Washington, on December 28, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-50 Filed 1-3-00; 8:45 am]
BILLING CODE 4910-13-U