[Federal Register Volume 60, Number 85 (Wednesday, May 3, 1995)]
[Proposed Rules]
[Pages 21774-21776]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-10829]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-35-AD]
Airworthiness Directives; Boeing Model 727-100 and -200 Series
Airplanes Equipped With an Engine Nose Cowl Installed in Accordance
With Supplemental Type Certificate (STC) SA4363NM
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 727-100 and -
200 series airplanes. This proposal would require replacing the
attachin-nutplates on certain engine nose cowls with washers and self-
locking nuts. This proposal is prompted by reports indicating that nose
cowls separated (or nearly separated) from the engines of certain
airplanes following failure of the engine fan blade and subsequent
vibration of the engine, which caused loosening of the attach bolts on
the nose cowl of the engine. The actions specified by the proposed AD
are intended to prevent the attach bolts from becoming loose, which
could result in subsequent separation of the nose cowl from the engine.
DATES: Comments must be received by June 12, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-35-AD, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056. Comments may be inspected at this location
between 9 a.m. and 3 p.m., Monday through Friday, except Federal
holidays.
The service information referenced in the proposed rule may be
obtained from VALSAN Partnership Ltd., Aviation Products Management,
Product Support Office, 39450 Third Street East, suite 121, Palmdale,
California 93550. This information may be examined at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington.
FOR FURTHER INFORMATION CONTACT: Phil Forde, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle
Aircraft Certification Office, 1601 Lind Avenue SW., Renton, Washington
98055-4056; telephone (206) 227-2771; 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. [[Page 21775]]
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-35-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-35-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA received reports from three operators of McDonnell Douglas
Model DC-9-80 series airplanes indicating that a nose cowl separated
from the engine of the airplane. In addition, the FAA received one
report indicating that the nose cowl nearly separated from an airplane
equipped with a Pratt & Whitney JT8D-200 series engine. These incidents
occurred following severe vibration of the engine due to failure of the
engine fan blade. Such vibration of the engine could cause the attach
bolts on the nose cowl of the engine to become loose. This condition,
if not corrected, could result in separation of the nose cowl from the
engine of the airplane.
On December 2, 1994, the FAA issued AD 94-25-06, amendment 39-9090
(59 FR 64566, December 15, 1994), to address this unsafe condition on
McDonnell Douglas Model DC-9-80 series airplanes and Model MC-88
airplanes. Subsequently, the FAA has determined that certain Boeing
Model 727-100 and -200 series airplanes are equipped with an engine
nose cowl installed in accordance with Supplemental Type Certificate
(STC) SA4363NM, which is identical to the engine nose cowl installed on
the McDonnell Douglas airplanes affected by AD 94-25-06. Therefore, the
FAA has determined that these Boeing Model 727-100 and -200 series
airplanes also are subject to the addressed unsafe condition.
The FAA has reviewed and approved VALSAN B727-RE Service Bulletin
71-006, Revision 1, dated March 3, 1995, which describes procedures for
replacing the attaching nutplates of the No. 1 and No. 3 engine nose
cowls with washers and self-locking nuts. The replacement involves
removing the attaching nutplates from the No. 1 and No. 3 engine nose
cowls, reversing the installation direction of the attach bolt,
installing washers and self-locking nuts in place of the removed
nutplates, and increasing bolt torque values. Accomplishment of this
replacement will minimize the possibility of the attach bolts becoming
loose as a result of severe engine vibration, thereby minimizing the
possibility of the nose cowl separating from the engine.
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 replacing the attaching nutplates on certain
engine nose cowls with washers and self-locking nuts. The actions would
be required to be accomplished in accordance with the service bulletin
described previously.
As a result of recent communications with the Air Transport
Association (ATA) of America, the FAA has learned that, in general,
some operators may misunderstand the legal effect of AD's on airplanes
that are identified in the applicability provision of the AD, but that
have been altered or repaired in the area addressed by the AD. The FAA
points out that all airplanes identified in the applicability provision
of an AD are legally subject to the AD. If an airplane has been altered
or repaired in the affected area in such a way as to affect compliance
with the AD, the owner or operator is required to obtain FAA approval
for an alternative method of compliance with the AD, in accordance with
the paragraph of each AD that provides for such approvals. A note has
been included in this notice to clarify this long-standing requirement.
There are approximately 22 Model 727-100 and -200 series airplanes
of the affected design in the worldwide fleet. The FAA estimates that
19 airplanes of U.S. registry would be affected by this proposed AD,
that it would take approximately 6 work hours per airplane to
accomplish the proposed actions, and that the average labor rate is $60
per work hour. The cost for required parts would be negligible. Based
on these figures, the total cost impact of the proposed AD on U.S.
operators is estimated to be $6,840, or $360 per airplane.
The total 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 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:
Boeing: Docket 95-NM-35-AD.
Applicability: Model 727-100 and -200 series airplanes equipped
with an engine nose cowl installed in accordance with Supplemental
Type Certificate (STC) SA4363NM, certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
[[Page 21776]] 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 (c) 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 the attach bolts on the nose cowl of the engine from
becoming loose, and subsequent separation of the nose cowl from the
engine, accomplish the following:
(a) Within 12 months after the effective date of this AD,
replace the attaching nutplates of the No. 1 and No. 3 engine nose
cowls with washers and self-locking nuts in accordance with VALSAN
B727-RE Service Bulletin 71-006, Revision 1, dated March 3, 1995.
(b) As of the effective date of this AD, no person shall install
a nose cowl having part number 259-0002-501 or 259-0002-503 on any
airplane.
(c) 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.
(d) 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 April 27, 1995.
James V. Devany,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-10829 Filed 5-2-95; 8:45 am]
BILLING CODE 4910-13-U
