[Federal Register Volume 61, Number 21 (Wednesday, January 31, 1996)]
[Proposed Rules]
[Pages 3340-3341]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-1876]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-154-AD]


Airworthiness Directives; Boeing Model 767 Series Airplanes 
Equipped with Pratt & Whitney Model JT9D-7R4 Engines

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 Model 767 series 
airplanes. This proposal would require a visual inspection to verify 
proper clearance between the number 18 fuel nozzle secondary transfer 
fuel tube and the pylon drain tube of the engine, and various follow-on 
actions. The proposal would also require installation of clamps and 
associated fasteners between the environmental control system (ECS) 
controller tube and the pylon drain tube. This proposal is prompted by 
reports of chafing of the number 18 fuel nozzle secondary transfer fuel 
tube of the engine due to an improperly installed or loose pylon drain 
tube. The actions specified by the proposed AD are intended to prevent 
such chafing, which could lead to subsequent fuel leakage and a 
possible engine fire.

DATES: Comments must be received by March 26, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-154-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: Monica Gandara Merritt, Aerospace 
Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington; 
telephone (206) 227-2683; fax (206) 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 95-NM-154-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-103, Attention: Rules 
Docket No. 95-NM-154-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports of chafing of the number 18 fuel 
nozzle secondary transfer fuel tube, which resulted in excessive fuel 
leakage on one airplane and an engine fire on another airplane. These 
incidents occurred on Boeing Model 767 series airplanes equipped with 
Pratt & Whitney Model JT9D-7R4 engines. In the engine fire incident, 
investigation revealed that the cause of the chafing was attributed to 
the installation of the wrong engine fuel manifold, which did not 
provide for adequate clearance for the fuel tube. In the fuel leakage 
incident, investigation revealed that the cause of the chafing was 
attributed to an improperly installed or loose pylon drain tube, which 
contacted the fuel transfer tube and subsequently chafed against it. 
Chafing of the number 18 fuel nozzle secondary transfer fuel tube of 
the engine, if not detected and corrected in a timely manner, could 
lead to fuel leakage and, consequently, a possible engine fire.
    The FAA has reviewed and approved Boeing Alert Service Bulletin 
767-71A0082, dated July 6, 1995, which describes procedures for 
installation of clamps and associated fasteners between the 
environmental control system (ECS) and the pylon drain tube. The 
installation will ensure that proper clearance between the engine fuel 
manifold and the pylon drain line is maintained.
    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 installation of clamps and associated 
fasteners between the ECS controller tube and the pylon drain tube. The 
actions would be required to be accomplished in accordance with the 
alert service bulletin described previously.
    Additionally, the proposed AD would require a visual inspection to 
verify that proper clearance (0.5 inch) exists between the number 18 
fuel nozzle secondary transfer fuel tube and the pylon drain tube of 
the engine; and follow-on actions (i.e., visual inspection for damage, 
relocation of the pylon tube, and repair or replacement of a damaged 
tube). The FAA has determined that accomplishing only the installation 
of clamps and associated fasteners, as described previously, would not 
eliminate any damage from chafing that may currently exist on the fuel 
tube. The FAA has determined that any existing chafing damage must be 
identified and corrected.
    There are approximately 93 Model 767 series airplanes equipped with 
Pratt & Whitney Model JT9D-7R4 engines of the affected design in the 
worldwide fleet. The FAA estimates that 30 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
4 work hours per airplane to accomplish the proposed actions, and that 
the average labor rate is $60 per work hour. Required parts 

[[Page 3341]]
would cost approximately $31 per airplane. Based on these figures, the 
cost impact of the proposed AD on U.S. operators is estimated to be 
$8,130, or $271 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.
    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 USC 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

Boeing: Docket 95-NM-154-AD.

    Applicability: Model 767 series airplanes having line position 1 
through 329 inclusive; equipped with Pratt & Whitney Model JT9D-7R4 
engines; 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 use the authority 
provided in paragraph (b) of this AD to request approval from the 
FAA. This approval may address either no action, if the current 
configuration eliminates the unsafe condition; or different actions 
necessary to address the unsafe condition described in this AD. Such 
a request should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent chafing of the number 18 fuel nozzle secondary 
transfer fuel tube of the engine, and subsequent fuel leakage and 
possible engine fire, accomplish the following:
    (a) Within 6 months after the effective date of this AD, perform 
a visual inspection to verify proper clearance (0.5 inch) between 
the number 18 fuel nozzle secondary transfer fuel tube and the pylon 
drain tube of the engine.
    (1) If the clearance is equal to or greater than 0.5 inch, prior 
to further flight, install clamps and associated fasteners between 
the environmental control system (ECS) and the pylon drain tube, in 
accordance with Boeing Alert Service Bulletin 767-71A0082, dated 
July 6, 1995.
    (2) If the clearance is less than 0.5 inch, prior to further 
flight, perform a visual inspection to detect damage of the number 
18 fuel nozzle secondary transfer fuel tube and the pylon drain 
tube.
    (i) If no damage is detected, or if any damage to the number 18 
fuel nozzle secondary transfer tube is less than or equal to 0.002 
inch deep and if any damage to the drain tube is less than or equal 
to 0.010 inch deep, prior to further flight, relocate the pylon 
drain tube to meet the 0.5 inch specification. After accomplishing 
the relocation, prior to further flight, install the clamps and 
associated fasteners between the ECS and the pylon drain tube, in 
accordance with Boeing Alert Service Bulletin 767-71A0082, dated 
July 6, 1995.
    (ii) If any damage to the number 18 fuel tube is greater than 
0.002 inch deep, or if any damage to the drain tube is greater than 
0.010 inch deep, prior to further flight, repair or replace the 
damaged tube, in accordance with Section 28-00-10 of the Overhaul 
Manual. After accomplishing the repair or replacement, prior to 
further flight, install the clamps and associated fasteners between 
the ECS and the pylon drain tube, in accordance with Boeing Alert 
Service Bulletin 767-71A0082, dated July 6, 1995.
    (b) 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.

    (c) 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 January 25, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-1876 Filed 1-30-96; 8:45 am]
BILLING CODE 4910-13-U