[Federal Register Volume 61, Number 130 (Friday, July 5, 1996)]
[Rules and Regulations]
[Pages 35127-35129]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-16652]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-154-AD; Amendment 39-9684; AD 96-14-02]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 767 Series Airplanes
Equipped With Pratt & Whitney Model JT9D-7R4 Engines
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
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. This amendment also requires
the installation of clamps and associated fasteners between the
environmental control system (ECS) controller tube and the pylon drain
tube. This amendment 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 this AD are intended to prevent such chafing, which could lead to
subsequent fuel leakage and a possible engine fire.
DATES: Effective August 9, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of August 9, 1996.
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: Monica Merritt, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton,
[[Page 35128]]
Washington; telephone (206) 227-2683; fax (206) 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 January 31, 1996 (61
FR 3340). That action proposed to 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. That action also proposed to require the installation of
clamps and associated fasteners between the environmental control
system (ECS) controller tube and the pylon drain tube.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Support for the Proposal
One commenter supports the proposal.
Request To Revise Description of Affected Component
One commenter, Boeing, requests that all references in the proposed
rule to the ``ECS'' controller tube be changed to ``the high pressure
controller muscle air tube.'' The commenter states that the high
pressure controller and muscle air tube are components of the airplane
pneumatic system, which provides engine bleed air to various airplane
systems, including the ECS.
The FAA agrees with the commenter's suggestion that the revised
wording may be a more accurate description of the subject component.
However, the service information (Boeing Service Bulletin 767-71A0082)
that is referenced in the AD uses the term ``ECS controller tube''
throughout the procedures it contains relative to the modification. In
light of this, the FAA finds that using the term ``ECS controller
tube'' in the final rule will maintain consistency with the terminology
used in the referenced service bulletin and, thereby, will avoid
confusion.
Request To Revise Description of Service History
This same commenter requests that the description of the incidents
that prompted the AD be revised. The commenter points to a specific
statement that appeared in the Discussion section of the preamble to
the notice: ``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.'' The commenter states that subsequent
investigation of this particular incident revealed that an acceptable
clearance could be maintained even if the wrong configuration of number
18 fuel tube was installed. The contributing factor to the chafing of
the number 18 fuel tube was the mis-installation of the pylon drain
tube.
The FAA acknowledges this new information. However, it in no way
affects the intent of or need for this AD. Since the Discussion section
is not repeated in the final rule, no change to the rule is necessary.
Request To Clarify Damage Specifications
This same commenter requests that proposed paragraph (a)(2) be
revised to clarify the amount of damage to the number 18 fuel tube and
the pylon drain tube of the engine that would require replacement or
repair of those items. The commenter points out that the damage
specifications indicated in the proposal are different from those
specified in both the 767 Maintenance Manual and the Pratt & Whitney
JT9D Engine Manual.
The FAA concurs that clarification is necessary. Based on
information contained in the two manuals referenced by the commenter,
the FAA finds that repair or replacement must be accomplished if damage
to the number 18 fuel tube is greater than 0.003 inch, and if damage to
the pylon drain tube is greater than 0.004 inch. Paragraphs (a)(2)(i)
and (a)(2)(ii) of the final rule have been changed accordingly.
Additionally, those paragraphs have been revised to include reference
to the 767 Maintenance Manual and the Pratt & Whitney JT9D Engine
Manual as sources of information relative to damage measurements.
Request To Extend Compliance Time
One commenter requests that the compliance time for accomplishing
the inspection be extended from the proposed 6 months to 12 months. The
commenter, a non-U.S. operator, requests this extension in order to
accommodate the modification of a number of engines in its fleet that
currently are equipped with different clamps.
The FAA does not concur with the commenter's request to extend the
compliance time. In developing an appropriate compliance time for this
action, the FAA considered not only the degree of urgency associated
with addressing the subject unsafe condition, but the availability of
required parts and the practical aspect of accomplishing the inspection
and installing the modification within an interval of time that
parallels normally scheduled maintenance for the majority of affected
operators. The FAA has found that an ample number of modification parts
will be available to accommodate the affected fleet within the 6-month
compliance period. In light of these factors, the FAA finds that the
compliance time, as proposed, is appropriate. However, under the
provisions of paragraph (b) of the final rule, the FAA may approve
requests for adjustments to the compliance time if data are submitted
to substantiate that such an adjustment would provide an acceptable
level of safety.
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 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
will be affected by this AD, that it will take approximately 4 work
hours per airplane to accomplish the required actions, and that the
average labor rate is $60 per work hour. Required parts will cost
approximately $31 per airplane. Based on these figures, the cost impact
of the 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 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,
[[Page 35129]]
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:
96-14-02 Boeing: Amendment 39-9684. 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 request approval for an
alternative method of compliance in accordance with paragraph (b) 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 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 0.003
inch deep, as specified in Section 72-09-71 of Pratt & Whitney JT9D
Engine Manual, and if any damage to the drain tube is less than or
equal to 0.004 inch deep, as specified in the Boeing 767 Maintenance
Manual 28-22-07: 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
0.003 inch deep, as specified in Section 72-09-71 of the Pratt &
Whitney JT9D Engine Manual; or if any damage to the drain tube is
greater than 0.004 inch deep, as specified in the Boeing 767
Maintenance manual 28-22-07: Prior to further flight, repair or
replace the damaged tube, in accordance with Section 28-00-10 of the
Boeing 767 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.
(d) The installation of the clamps and associated fasteners
shall be done in accordance with Boeing Alert Service Bulletin 767-
71A0082, dated July 6, 1995. 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.
(e) This amendment becomes effective on August 9, 1996.
Issued in Renton, Washington, on June 25, 1996.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-16652 Filed 7-3-96; 8:45 am]
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