[Federal Register Volume 59, Number 105 (Thursday, June 2, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-13236]
[[Page Unknown]]
[Federal Register: June 2, 1994]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 93-NM-167-AD; Amendment 39-8923; AD 94-11-07]
Airworthiness Directives; British Aerospace Model BAC 1-11-200
and -400 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to all British Aerospace Model BAC 1-11-200 and -400 series
airplanes, that requires inspection of the landing gear brakes for
wear, and replacement of the brakes if the wear limits prescribed in
this amendment are not met. This amendment also requires that the
specified maximum brake wear limits be incorporated into the FAA-
approved maintenance inspection program. This amendment is prompted by
an accident in which a transport category airplane executed a rejected
takeoff (RTO) and was unable to stop on the runway due to worn brakes;
and the subsequent review of allowable brake wear limits for all
transport category airplanes. The actions specified by this AD are
intended to prevent the loss of brake effectiveness during a high
energy RTO.
EFFECTIVE DATE: July 5, 1994.
ADDRESSES: Information pertaining to this rulemaking action may be
examined at the Federal Aviation Administration (FAA), Transport
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton,
Washington.
FOR FURTHER INFORMATION CONTACT: Mark Quam, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-2145; fax (206) 227-1320.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations to include an airworthiness directive (AD) that is
applicable to all British Aerospace Model BAC 1-11-200 and -400 series
airplanes was published in the Federal Register on January 27, 1994 (59
FR 3798). That action proposed to require the inspection of certain
landing gear brakes for wear, and the replacement of brakes if the wear
limits prescribed in the proposal are not met. That action also
proposed that the specified maximum brake wear limits be incorporated
into the FAA-approved maintenance inspection program.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
One commenter supports the proposal.
Another commenter requests that NOTE 2 of the proposal be
clarified. This commenter points out that proposed NOTE 2 states, ``* *
* Brake units having wear indicators set at 1.06 inch will be
considered to be fully worn when either wear indicator pin is 1.0 inch
or less above the surface of the carrier. * * *'' In effect, this
wording permits a total brake wear (from new to fully worn brake) of
only 0.06 inch. This clearly is incorrect. This commenter states that a
correctly set wear indicator pin protrudes above the surface of the
carrier when in normal operation, but will be flush with the surface
when the brake is fully worn. Thus, the dimension by which the pin
protrudes above the surface of the carrier is the amount of wear still
available. Therefore, a wear indicator pin set for the existing limit
of 1.06 inch will protrude above the surface of the carrier by 0.06
inch when the new wear limit of 1.00 inch is reached. The FAA concurs
and has revised NOTE 2 of the final rule to clarify this point.
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 change previously
described. The FAA has determined that this change will neither
increase the economic burden on any operator nor increase the scope of
the AD.
There are approximately 100 Model BAC 1-11-200 and -400 series
airplanes of the affected design in the worldwide fleet.
The FAA estimates that 10 Model BAC 1-11-200 series airplanes of
U.S. registry and 2 U.S. operators of these airplanes will be affected
by this proposed AD. For these airplanes and operators, although the
rule requires the incorporation of maximum brake wear limits into the
FAA-approved maintenance inspection program, no other specific
additional action, inspection, or part replacement costs relative to
that requirement is involved; such actions are currently a part of the
current maintenance program. However, it is estimated that it will take
approximately 1 work hour, at an average labor rate of $55 per work
hour, for each operator to incorporate the revision into its FAA-
approved maintenance inspection program. Based on these figures, the
total cost impact of the requirement to revise the FAA-approved
maintenance inspection program on U.S. operators of Model BAC 1-11-200
series airplanes is estimated to be $110, or $55 per operator.
The FAA estimates that 20 Model BAC 1-11-400 series airplanes of
U.S. registry and 19 U.S. operators of these airplanes will be affected
by this AD. It is estimated that it will take approximately 1 work
hour, at an average labor rate of $55 per work hour, for each operator
to incorporate the revision into its FAA-approved maintenance
inspection program. Based on these figures, the total cost impact of
that requirement on U.S. operators of Model BAC 1-11-400 series
airplanes is estimated to be $1,045, or $55 per operator.
Additionally, the FAA estimates that for operators of Model BAC 1-
11-400 series airplanes, it will take approximately 2 work hours per
airplane to shorten the wear pins for replacement brakes, and 8 work
hours per airplane to change the brakes, at an average labor rate of
$55 per work hour. The cost of required parts to accomplish the change
in wear limits for these airplanes (that is, the cost resulting from
the requirement to change the brakes before they are worn to their
previously approved limits for a one-time change) is estimated to be
$912 per airplane. Based on these figures, the total cost impact of
these requirements on U.S. operators of Model BAC 1-11-400 series
airplanes is estimated to be $29,240, or $1,462 per airplane.
The total 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.
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, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 14 CFR part
39 of the Federal Aviation Regulations as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
94-11-07 British Aerospace: Amendment 39-8923. Docket 93-NM-167-AD.
Applicability: All Model BAC 1-11-200 and -400 series airplanes,
certificated in any category.
Compliance: Required as indicated, unless accomplished
previously.
To prevent the loss of brake effectiveness during a high energy
rejected takeoff (RTO), accomplish the following:
(a) Within 180 days after the effective date of this AD,
accomplish paragraphs (a)(1) and (a)(2) of this AD.
(1) Inspect main landing gear brakes having the brake part
numbers listed below for wear. Any brake worn more than the maximum
wear limit specified below must be replaced, prior to further
flight, with a brake within that limit.
British Aerospace Model BAC 1-11-200 and -400 Series Airplanes Equipped
With Bendix Brakes
------------------------------------------------------------------------
Maximum brake wear
Airplane model Brake part No. limit (inch/mm)
------------------------------------------------------------------------
BAC 1-11-200 2601225-1.............. 0.75 inch (19.1 mm)
BAC 1-11-400 2601240-1.............. 1.0 inch (25.4 mm)
------------------------------------------------------------------------
Note 1: Measuring instructions for Bendix brakes can be found in
Revision 4 of the Allied Signal Component Maintenance Manual.
Note 2: Revision 4 of the Allied Signal Component Maintenance
Manual specifies a brake wear limit of 1.06 inch for brake part
number 2601240-1. That brake wear limit is superseded by the brake
wear limit of 1.0 inch specified above for that brake part number.
Revision 5 of the Allied Signal Component Maintenance Manual will
reflect the revised brake wear limit of 1.0 inch. Brake units having
wear indicators set at 1.06 inch will be considered to be fully worn
when either wear indicator pin is 0.06 inch or less above the
surface of the carrier, provided the wear indicator pin has not been
shortened on that brake unit.
Note 3: Each operator should provide a method of identifying
modified brakes until Revision 5 of the Allied Signal Component
Maintenance Manual has been issued. Revision 5 of the manual will
define a method of brake identification and reflect the brake wear
limits specified above. A paint scheme similar to that used to
differentiate between new and refurbished brakes could be used, for
example, if a different color is used.
(2) Incorporate into the FAA-approved maintenance inspection
program the maximum brake wear limits specified in paragraph (a)(1)
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, Standardization Branch, ANM-113,
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,
Standardization Branch, ANM-113.
Note 4: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(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) This amendment becomes effective on July 5, 1994.
Issued in Renton, Washington, on May 25, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-13236 Filed 6-1-94; 8:45 am]
BILLING CODE 4910-13-U
