AD Amdt-39-10012

[Federal Register Volume 62, Number 85 (Friday, May 2, 1997)]
[Rules and Regulations]
[Pages 24015-24017]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 97-11334]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-66-AD; Amendment 39-10012; AD 97-08-51]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) T97-08-51 that was sent 
previously to all known U.S. owners and operators of Boeing Model 767 
series airplanes by individual telegrams. This AD requires an 
inspection to ensure that all bolts of the hinge fitting assembly 
support beam on both the left-and right-hand outboard trailing edge 
flaps are the correct length and type, and correction of any 
discrepancy found. This action is prompted by a report indicating that 
a 20-foot section of the right-hand outboard trailing edge flap 
separated from the airplane due to failure of four bolts of the most 
inboard hinge fitting. The actions specified by this AD are intended to 
detect and correct such failed bolts, which could result in loss of an 
outboard trailing edge flap, and consequent reduced controllability of 
the airplane.

DATES: Effective May 7, 1997, to all persons except those persons to 
whom it was made immediately effective by telegraphic AD T97-08-51, 
issued on April 2, 1997, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 7, 1997.
    Comments for inclusion in the Rules Docket must be received on or 
before July 1, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 97-NM-66, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The applicable service information 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; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Todd Martin, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington; telephone (206) 227-2781; 
Fax (206) 227-1181.

SUPPLEMENTARY INFORMATION: On April 2, 1997, the FAA issued telegraphic 
AD T97-08-51, which is applicable to all Boeing Model 767 series 
airplanes.
    That action was prompted by a report indicating that a 20-foot 
section of the right-hand outboard trailing edge flap separated from a 
Boeing Model 767 series airplane during approach for landing. During 
the approach, a ``spoiler up flaps 15'' configuration was used as part 
of a high descent rate approach, which is typically associated with 
high applied loads on the hinge fittings of the outboard trailing edge 
flap. Additionally, the numbers 9 and 12 spoilers were damaged, which 
suggests that, upon separation from the airplane, the flap hit the 
spoilers. Analysis of the flap structure revealed that four bolts of 
the most inboard hinge fitting had failed.
    On-site investigation of the four failed bolts revealed that one 
bolt had been completely severed due to fatigue that occurred some time 
prior to the loss of the section of the flap. The investigation also 
revealed that two of the bolts had been partially severed (roughly 20-
30 percent of the bolt diameter), and that one bolt failed from static 
overload.
    Failure of the bolts, if not detected and corrected, could result 
in loss of an outboard trailing edge flap, and consequent reduced 
controllability of the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
767-27A0151, Revision 1, dated April 2, 1997, which describes 
procedures for the following actions:
    <bullet> Performing a torque check inspection to ensure that all 
bolts of the hinge fitting assembly support beam on both the left-and 
right-hand outboard trailing edge flaps are within specified torque 
range;
    <bullet> An inspection to verify the bolt length and type of all 
the bolts of both hinge fittings, and correction of any discrepancy 
found;
    <bullet> Replacing all six assembly bolts with new or serviceable 
bolts, or performing a dye penetrant inspection

[[Page 24016]]

to detect cracking and/or discrepancies of any bolt that is below the 
threshold of the torque check;
    <bullet> Replacing any cracked or damaged bolt with a new or 
serviceable bolt; and
    <bullet> Performing an inspection to ensure that shims are 
installed, and an inspection to ensure that the radius filler is 
correctly installed.

Explanation of Requirements of the Rule

    Since the unsafe condition described is likely to exist or develop 
on other airplanes of the same type design, the FAA issued Telegraphic 
AD T97-08-51 to prevent separation of the outboard trailing edge flap 
due to failed bolts of the hinge fitting. The AD requires an inspection 
to ensure that all bolts of the hinge fitting assembly support beam on 
both the left-and right-hand outboard trailing edge flaps are within 
specified torque range. Additionally, this AD requires an inspection to 
ensure that all bolts of the hinge fitting assembly support beam on 
both the left-and right-hand outboard trailing edge flaps are the 
correct length and type, and correction of any discrepancy found. For 
any bolt that is outside the specified torque range, this AD requires 
either replacing all six bolts of the hinge fitting assembly with new 
or serviceable bolts, or performing a dye penetrant inspection to 
detect cracking or discrepancies of the bolts. For airplanes on which 
any cracked or discrepant bolt is found, this AD requires replacement 
of the bolt with a new or serviceable bolt.
    The actions are required to be accomplished in accordance with the 
alert service bulletin previously described.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual telegrams 
issued on April 2, 1997, to all known U.S. owners and operators of 
Boeing Model 767 series airplanes. These conditions still exist, and 
the AD is hereby published in the Federal Register as an amendment to 
section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to 
make it effective to all persons.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 97-NM-66-AD.'' The postcard will be date stamped and 
returned to the commenter.

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.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, 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:

97-08-51 Boeing: Amendment 39-10012. Docket 97-NM-66-AD.

    Applicability: Model 767 series airplanes, 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 (e) 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 separation of the outboard trailing edge flap from 
the airplane due to failed bolts of the attach fitting, accomplish 
the following:
    (a) Perform an inspection to check the bolt torque, bolt length, 
and type of all bolts of both hinge fittings on the left-and right-
hand outboard trailing edge flaps, in accordance with Boeing Alert 
Service Bulletin 767-27A0151, Revision 1, dated
    April 2, 1997. Perform these inspections at the time specified 
in paragraph (a)(1) or (a)(2) of this AD, as applicable.
    (1) For airplanes that have accumulated 15,000 total flight 
cycles or more, or 37,500 total flight hours or more, as of the 
effective date of this AD: Perform the inspections within 15 days 
after the effective date of this AD.
    (2) For all other airplanes: Perform the inspections at the 
later of the times specified

[[Page 24017]]

in paragraphs (a)(2)(i) and (a)(2)(ii) of this AD.
    (i) Prior to the accumulation of 10,000 total flight cycles, or 
25,000 total flight hours, whichever occurs first.
    (ii) Within 30 days after the effective date of this AD.
    (b) If any bolt of the hinge fittings of the left-and right-hand 
outboard trailing edge flaps is below the torque check threshold 
specified in Boeing Alert Service Bulletin 767-27A0151, Revision 1, 
dated April 2, 1997: Prior to further flight, accomplish the action 
specified in paragraph (b)(1) or (b)(2) of this AD in accordance 
with the alert service bulletin.
    (1) Perform a dye penetrant inspection of all the bolts of the 
hinge fitting to detect any cracking or discrepancy.
    (i) If no cracking or discrepancy is detected, reinstall the 
bolt using new nuts and washers.
    (ii) If any cracking or discrepancy is detected, replace the 
cracked or discrepant bolt with a new or serviceable bolt.
    (2) Replace all of the bolts of both hinge fittings with new or 
serviceable bolts.
    (c) If the length or type of any bolt of the hinge fittings of 
the left-and right-hand outboard trailing edge flaps is outside the 
specifications of Boeing Alert Service Bulletin 767-27A0151, 
Revision 1, dated April 2, 1997: Prior to further flight, replace 
the bolt with a new or serviceable bolt in accordance with the alert 
service bulletin.
    (d) Within 10 days after accomplishing the actions required by 
this AD, submit a report describing any cracking, damage, or any 
torque check of any bolt of either hinge fitting that was below the 
threshold of the torque check specified by this AD, to the Manager, 
Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056; fax (206) 227-1181. Information 
collection requirements contained in this regulation have been 
approved by the Office of Management and Budget (OMB) under the 
provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et 
seq.) and have been assigned OMB Control Number 2120-0056.
    (e) 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.

    (f) 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.
    (g) The actions shall be done in accordance with Boeing Alert 
Service Bulletin 767-27A0151, Revision 1, dated April 2, 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, ransport 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.
    (h) This amendment becomes effective on May 7, 1997, to all 
persons except those persons to whom it was made immediately 
effective by telegraphic AD T97-08-51, issued on April 2, 1997, 
which contained the requirements of this amendment.

    Issued in Renton, Washington, on April 25, 1997.
Neil D. Schalekamp,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-11334 Filed 5-1-97; 8:45 am]
BILLING CODE 4910-13-U