[Federal Register Volume 60, Number 19 (Monday, January 30, 1995)]
[Rules and Regulations]
[Pages 5566-5568]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-1850]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 94-NM-236-AD; Amendment 39-9129; AD 95-02-10]
Airworthiness Directives; Boeing Model 757 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to certain Boeing Model 757 series airplanes. This action
requires replacement of the bolts, nuts, and washers that attach the
support bracket at the Number 4 and Number 5 transmissions to the wing
flap structure. This amendment is prompted by a report of damage to the
left inboard trailing edge flap. The actions specified in this AD are
intended to prevent these airplanes from taking off with broken bolts
that attach the transmission bracket to the wing flap track structure,
which could result in the airplane rolling at liftoff.
DATES: Effective February 14, 1995.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of February 14, 1995.
Comments for inclusion in the Rules Docket must be received on or
before March 31, 1995.
[[Page 5567]] ADDRESSES: Submit comments in triplicate to the Federal
Aviation Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-236-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
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 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: Carrie Sumner, Aerospace Engineer,
Airframe Branch, ANM-121S, FAA, Transport Airplane Directorate, Seattle
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056; telephone (206) 227-2778; fax (206) 227-1181.
SUPPLEMENTARY INFORMATION: Recently, the FAA has received a report of
damage to the left inboard trailing edge flap on the wing of a Boeing
Model 757 series airplane when the flaps were retracted after the
airplane had landed. Investigation revealed that six bolts on the
attachment bracket of the inboard flap drive had sheared off when the
flaps were retracted. Further investigation revealed that the Number 3
inboard flap outboard drive had disconnected inside the angle gear box,
while the Number 4 inboard flap inboard drive continued to retract.
This caused a flap skew, which applied sufficient load on the drive
screw to fracture the six bolts that attach the Number 4 transmission
bracket to its mating flap track. Analysis showed that those six bolts,
which were made of titanium, do not meet the designed limit load. If an
airplane attempts to take off with broken bolts that attach the
transmission bracket to the flap track structure, the result may be the
airplane rolling at liftoff.
The FAA has reviewed and approved Boeing Alert Service Bulletin
757-27A0118, dated December 15, 1994, which describes procedures for
replacement of the six bolts, nuts, and washers that attach the support
bracket at the Number 4 and Number 5 transmission to the inboard
trailing edge flap system. The replacement bolts, nuts, and washers
(kit number 012N8037) are made of Inconel 718 material, which is
stronger and will sustain the designed limit load.
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design, this AD is
being issued to prevent these airplanes from taking off with broken
bolts that attach the transmission bracket to the flap track structure,
which could result in the airplane rolling at liftoff. This AD requires
replacement of the bolts, nuts, and washers that attach the support
bracket at the Number 4 and Number 5 transmission to the inboard
trailing edge flap system, with items made of Inconel 718 material. The
actions are required to be accomplished in accordance with the alert
service bulletin described previously.
This AD applies only to airplanes having line numbers 181 through
647, inclusive. The subject six-bolt attachment configuration was
incorporated on airplanes starting at line position 181.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
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 94-NM-236-AD.'' The postcard will be date stamped and
returned to the commenter.
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. 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:
95-02-10 Boeing: Amendment 39-9129. Docket 94-NM-236-AD.
Applicability: Model 757 series airplanes having line numbers
181 through 647 inclusive, certificated in any category.
[[Page 5568]] 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) 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 these airplanes from taking off with broken bolts
that attach the transmission bracket to the flap track structure,
which could result in the airplane rolling at liftoff, accomplish
the following:
(a) Within 60 days after the effective date of this AD, remove
the bolts, nuts, and washers that attach the support bracket at the
Number 4 and Number 5 transmission for the inboard trailing edge
flap system and install kit number 012N8037, in accordance with
Boeing Alert Service Bulletin 757-27A0118, dated December 15, 1994.
(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
Secs. 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 shall be done in accordance with Boeing
Alert Service Bulletin 757-27A0118, dated December 15, 1994. 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 February 14, 1995.
Issued in Renton, Washington, on January 19, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-1850 Filed 1-27-95; 8:45 am]
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