[Federal Register Volume 63, Number 63 (Thursday, April 2, 1998)]
[Rules and Regulations]
[Pages 16096-16098]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-8350]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-50-AD; Amendment 39-10433; AD 98-07-13]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 767-200 and -300 Series
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to certain Boeing Model 767-200 and -300 series airplanes,
that requires a one-time inspection for worn or broken wire bundles in
the ceiling above the main passenger door and repair, if necessary; and
relocation of the wire bundles to prevent chafing. This amendment is
prompted by a report indicating that the opening of the main passenger
door caused the door liner and a ceiling panel to chafe and ultimately
break wires installed in this area. The actions specified by this AD
are intended to prevent these wires from becoming worn or breaking,
which could lead to the failure of several systems, such as the fuel
shutoff valves, and may contribute to the inability of the flight crew
to stop the flow of fuel to the engines in the event of an engine fire.
DATES: Effective May 7, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of May 7, 1998.
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: Stephen S. Oshiro, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056; telephone (425) 227-2793; 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 767-200 and -
300 series airplanes was published in the Federal Register on June 6,
1997 (62 FR 31021). That action proposed to require a one-time
inspection for worn or broken wire bundles in the ceiling above the
main passenger door and repair, if necessary; and relocation of the
wire bundles to prevent chafing.
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
Two commenters support the proposed rule.
Request To Add New Service Information
One commenter requests including the phrase ``as amended by Notice
of Status Change 767-33-0052 NSC 01, dated May 9, 1996'' in the final
rule after each reference to Boeing Service Bulletin 767-33-0052,
Revision 1, dated December 8, 1994. This commenter states that the
Notice of Status Change (NSC) specifies that a larger wire clamp is
required than was specified in Revision 1 of the service bulletin.
The FAA concurs. The FAA has determined that the wire bundle clamp
specified in the previously referenced service bulletin may be too
small for two of the wire bundles on Model 767-200 and -300 series
airplanes. For this reason, the FAA considers that the larger wire
clamp specified in the previously referenced NSC will provide operators
with the proper size clamp, and has changed the final rule accordingly.
Request To Change Discussion Section of Proposal
One commenter requests two changes to the wording in the Discussion
section of the proposal:
1. In the first sentence of the second paragraph, which reads
``Because these wires are connected to such safety systems as the fuel
shutoff valves for the engines * * *,'' the commenter requests deleting
the word ``safety'' from ``safety system.'' The commenter states that
it is incorrect to identify these systems as ``safety systems'' because
if any of the systems fail, a second failure would be required to cause
a safety problem.
The FAA concurs partially. The FAA does not agree that these
systems are unrelated to safety. When evaluating the loss of functions
that protect the airplane from hazardous events, the FAA assumes the
existence of the
[[Page 16097]]
hazard. In the case of worn or broken wiring to the engine fuel shutoff
valve, the FAA considers that the inability of the flight crew to close
the shutoff valve, given the existence of an engine fire, is a
hazardous condition that warrants mandatory corrective action. The FAA
considers that changing ``safety systems'' to ``systems related to
airplane or passenger safety'' would add clarity to the final rule;
however, no change to this final rule is necessary since neither the
Discussion section nor the term ``safety systems'' appear in the final
rule.
2. In the second sentence of the second paragraph, the commenter
states that the following statement should be deleted from the final
rule: ``Such failure of the fuel shutoff valves, for example, would
prevent the flight crew from stopping the flow of fuel to the engines
in the event of a fire.'' The commenter states that this statement is
incorrect because ``the subject wiring failure will affect only the
fire handle electrical path to the fuel shutoff valve.'' The commenter
maintains that the redundant fuel control switch path would be
unaffected by this failure and that the valve could be closed in case
of an engine fire.
The FAA concurs partially. The FAA does not agree that the valve
could be closed in case of an engine fire if the fuel control switch
failed; however, the FAA does agree to clarify the wording of the final
rule in certain sections.
After evaluating the design of the engine fuel shutoff valve system
of the Model 767 series airplane, the FAA has determined the following.
First, although in the event of the subject wiring failure, the fuel
shutoff valve could be closed via the engine fuel shutoff valve, the
ability to close this valve is dependent on the actuation of the fuel
control switch by the flight crew before the engine fire handle is
pulled, as specified by the Emergency Procedures section of the Model
767 Airplane Flight Manual. Second, the engine fuel shutoff valve
cannot be closed if the fire handle is pulled before the fuel control
switch is placed in the ``Cutoff'' position.
Because of these findings, the FAA has determined that a procedural
deviation, such as pulling the fire handle first, could occur under
certain circumstances, which would result in the inability to stop the
flow of fuel to an engine fire. Further, the FAA has determined that
the final rule should continue to identify the loss of fuel shutoff
capability as a possible consequence of the wire chafing condition.
The Discussion section does not appear in the final rule; however,
the FAA has changed the wording in the Summary section of this final
rule and the section that describes the unsafe condition to address the
commenter's concern. In these sections the final rule now reads ``Wire
bundle damage may contribute to the inability of the flight crew to
stop the flow of fuel to the engines in the event of an engine fire''
instead of ``* * * would prevent the flight crew * * *.''
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 403 Model 767-200 and -300 series airplanes
of the affected design in the worldwide fleet. The FAA estimates that
142 airplanes of U.S. registry will be affected by this AD.
It will take approximately 1 work hour per airplane to accomplish
the required inspection, at an average labor rate of $60 per work hour.
Based on these figures, the cost impact of the inspection on U.S.
operators is estimated to be $8,520, or $60 per airplane.
It will take approximately 57 work hours per airplane to accomplish
the required relocation of the wire bundles, at an average labor rate
of $60 per work hour. Required parts will cost approximately $200 per
airplane. Based on these figures, the cost impact of the required
relocation of the wire bundles on U.S. operators is estimated to be
$514,040, or $3,620 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:
98-07-13 Boeing: Amendment 39-10433. Docket 97-NM-50-AD.
Applicability: Model 767-200 and -300 series airplanes; as
listed in Boeing Service Bulletin 767-33-0052, Revision 1, dated
December 8, 1994, as revised by Notice of Status Change 767-33-0052
NSC 01, dated May 9, 1996; 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.
[[Page 16098]]
To prevent wires in the area above the main passenger door from
becoming worn or breaking, which could lead to the failure of
several systems, such as the fuel shutoff valves, and may contribute
to the inability of the flight crew to stop the flow of fuel to the
engines in the event of an engine fire, accomplish the following:
(a) Within 12 months after the effective date of this AD,
conduct a one-time inspection to detect worn or broken wires in the
wire bundles installed above the main passenger door, in accordance
with Boeing Service Bulletin 767-33-0052, Revision 1, dated December
8, 1994, as revised by Notice of Status Change 767-33-0052 NSC 01,
dated May 9, 1996. Prior to further flight, repair any worn or
broken wires and relocate the wire bundles inboard of this door, in
accordance with the service bulletin. Thereafter, no further action
is required by this AD.
Note 2: Inspection; repair, if necessary; and relocation of the
wire bundles accomplished prior to the effective date of this AD in
accordance with Boeing Service Bulletin 767-33-0052, dated April 2,
1992, is considered acceptable for compliance with the requirements
of paragraph (a) of this AD.
(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 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Manager, 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 actions shall be done in accordance with Boeing Service
Bulletin 767-33-0052, Revision 1, dated December 8, 1994; as revised
by Notice of Status Change 767-33-0052 NSC 01, dated May 9, 1996.
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 May 7, 1998.
Issued in Renton, Washington, on March 25, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-8350 Filed 4-1-98; 8:45 am]
BILLING CODE 4910-13-U