[Federal Register Volume 60, Number 122 (Monday, June 26, 1995)]
[Proposed Rules]
[Pages 32926-32929]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-15517]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 95-NM-97-AD]
Airworthiness Directives; McDonnell Douglas Model MD-11 Series
Airplanes Equipped With Pratt & Whitney Model PW4460 and PW4462 Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to certain McDonnell Douglas
Model MD-11 series airplanes, that currently requires a visual
inspection to detect cracks or discrepancies in the aft mount beam
assembly of the engines; and replacement of the cracked or discrepant
aft mount beam assembly with a new assembly, or a previously inspected
and re-identified assembly. That amendment was prompted by reports of
cracking in a certain aft mount beam assembly on Airbus Model A310
series airplanes. This action would continue to require the visual
inspection, and corrective actions for findings of cracking or
discrepancies. This action would require additional inspections to
detect cracks or discrepancies in the subject area, and follow-on
actions. The actions specified by the proposed AD are intended to
prevent cracks in the aft mount beam assembly of the engines, which
could result in loss of the capability of the aft mount beam assembly
to support engine [[Page 32927]] loads, and possible separation of the
engine from the airplane.
DATES: Comments must be received by August 21, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-97-AD, 1601 Lind Avenue, SW., Renton,
Washington 98055-4056. Comments may be inspected at this location
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal
holidays.
The service information referenced in the proposed rule may be
obtained from McDonnell Douglas Corporation, 3855 Lakewood Boulevard,
Long Beach, California 90846, Attention: Technical Publications
Business Administration, Department C1-L51 (2-60). This information may
be examined at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane
Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount
Boulevard, Lakewood, California.
FOR FURTHER INFORMATION CONTACT: Wahib Mina, Aerospace Engineer,
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification
Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone
(310) 627-5324; fax (310) 627-5210.
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.
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-97-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-97-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On May 22, 1995, the FAA issued AD 95-11-13, amendment 39-9246 (60
FR 28527, June 1, 1995), applicable to certain McDonnell Douglas Model
MD-11 series airplanes, to require a one-time visual inspection to
detect cracks or discrepancies in the aft mount beam assembly of the
engines; and replacement of the cracked or discrepant aft mount beam
assembly with a certain new assembly, or a certain previously inspected
and re-identified assembly. That action was prompted by reports of
cracking in an aft mount beam assembly having part number (P/N) 221-
0261-501 on Airbus Model A310 series airplanes. The requirements of
that AD are intended to prevent cracks in the aft mount beam assembly
of the engines, which could result in loss of the capability of the aft
mount beam assembly to support engine loads, and possible separation of
the engine from the airplane.
Aft mount beam assemblies having P/N 221-0261-501 also are
installed on McDonnell Douglas Model MD-11 series airplanes equipped
with Pratt & Whitney PW4460 and PW4462 engines. The FAA has determined
that these airplanes are also subject to the addressed unsafe
condition.
In the preamble to AD 95-11-13, the FAA indicated that it intended
to supersede that AD to require fluorescent penetrant and eddy current
inspections of the aft mount beam assembly, P/N 221-0261-501, of the
engines within 4,000 flight cycles after accomplishing the visual
inspection required by that AD. This action proposes to require the
addition of these inspection requirements.
The FAA previously reviewed and approved McDonnell Douglas Alert
Service Bulletin MD11-71A073, Revision 1, dated May 16, 1995, which
describes procedures for a one-time visual inspection to detect cracks
or discrepancies in the aft mount beam assembly, P/N 221-0261-501, of
engine numbers 1, 2, and 3. This alert service bulletin also describes
procedures for replacement of the cracked or discrepant aft mount beam
assembly with a new assembly having P/N 221-0261-503, or a previously
inspected and re-identified assembly having P/N 221-0261-501.
As a follow-on action to the visual inspection, this service
bulletin describes procedures for etch fluorescent penetrant and eddy
current inspections to detect cracks or discrepancies in the aft mount
beam assembly, P/N 221-0261-501, of engine numbers 1, 2, and 3. This
service bulletin also describes procedures for re-identifying and
installing the aft mount beam assembly, if no cracks or discrepancies
are detected during the fluorescent penetrant and eddy current
inspections; and for replacement of any cracked or discrepant assembly
found during these inspections.
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 supersede AD 95-11-13 to continue to require a one-
time visual inspection to detect cracks or discrepancies in the aft
mount beam assembly, P/N 221-0261-501, of engine numbers 1, 2, and 3,
and corrective actions for findings of cracking or discrepancies. The
proposed AD would also require etch fluorescent penetrant and eddy
current inspections to detect cracks or discrepancies in the subject
area, and follow-on actions. The actions would be required to be
accomplished in accordance with the alert service bulletin described
previously.
This proposed AD would also require that operators report results
of any inspection findings, positive or negative, to the FAA.
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.
[[Page 32928]]
There are approximately 57 Model MD-11 series airplanes equipped
with Pratt & Whitney Model PW4460 and PW4462 engines of the affected
design in the worldwide fleet. The FAA estimates that 17 airplanes of
U.S. registry would be affected by this proposed AD.
The visual inspection that was previously required by AD 95-11-13,
and retained in this proposal, would take approximately 2 work hours
per airplane to accomplish, at an average labor rate of $60 per work
hour. Based on these figures, the total cost impact of the visual
inspection requirement on U.S. operators is estimated to be $2,040, or
$120 per airplane. The FAA estimates that all affected U.S. operators
have already accomplished this action; therefore, the future cost
impact of this requirement is minimal.
The fluorescent penetrant and eddy current inspections that would
be required by this proposal would take approximately 15 work hours per
airplane to accomplish, at an average labor rate of 60 per work hour.
Based on these figures, the total cost impact of the proposed
fluorescent penetrant and eddy current inspection requirements of this
AD on U.S. operators is estimated to be $15,300, or $900 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 removing amendment 39-9246 (60 FR
28527, June 1, 1995), and by adding a new airworthiness directive (AD),
to read as follows:
McDonnell Douglas: Docket 95-NM-97-AD. Supersedes AD 95-11-13,
Amendment 39-9246.
Applicability: Model MD-11 series airplanes, equipped with Pratt
& Whitney Model PW4460 and PW4462 engines; as listed in McDonnell
Douglas Alert Service Bulletin MD11-71A073, Revision 1, dated May
16, 1995; 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 use the authority
provided in paragraph (e) of this AD 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 loss of the capability of the aft mount beam assembly
to support engine loads, and possible separation of the engine from
the airplane, accomplish the following:
(a) Within 60 days after June 16, 1995 (the effective date of AD
95-11-13, amendment 39-9246), perform a visual inspection to detect
cracks or discrepancies in the aft mount beam assembly, part number
(P/N) 221-0261-501, of engine numbers 1, 2, and 3, in accordance
with McDonnell Douglas Alert Service Bulletin MD11-71A073, Revision
1, dated May 16, 1995.
(1) If no cracks or discrepancies are detected, no further
action is required by paragraph (a) of this AD.
(2) If any crack or discrepancy is detected, prior to further
flight, replace the cracked or discrepant aft mount beam assembly
with a new assembly having P/N 221-0261-503, or an assembly having
P/N 221-0261-501 that has been previously inspected and re-
identified, in accordance with paragraph 3.B., Phase 2, of the
Accomplishment Instructions of the alert service bulletin.
Replacement shall be accomplished in accordance with the procedures
specified in the alert service bulletin.
(b) Within 4,000 flight cycles after accomplishing the visual
inspection required by paragraph (a) of this AD, perform etch
fluorescent penetrant and eddy current inspections to detect cracks
or discrepancies in the aft mount beam assembly, P/N 221-0261-501,
of engine numbers 1, 2, and 3, in accordance with McDonnell Douglas
Alert Service Bulletin MD11-71A073, Revision 1, dated May 16, 1995.
(1) If no cracks or discrepancies are detected, prior to further
flight, re-identify and install the aft mount beam assembly in
accordance with the alert service bulletin.
(2) If any crack or discrepancy is detected, prior to further
flight, replace the cracked or discrepant aft mount beam assembly
with a new assembly having P/N 221-0261-503, or an assembly having
P/N 221-0261-501 that has been previously inspected and re-
identified, in accordance with paragraph 3.B., Phase 2, of the
Accomplishment Instructions of the alert service bulletin.
Replacement shall be accomplished in accordance with the procedures
specified in the alert service bulletin.
(c) Within 10 days after accomplishing any inspection required
by this AD, report inspection results, positive or negative, to the
Manager, Los Angeles Aircraft Certification Office (ACO), FAA,
Transport Airplane Directorate, 3960 Paramount Boulevard, Lakewood,
California 90712; fax (310) 627-5210. Information collection
requirements contained in this regulation have been approved by the
Office of Management and Budget (OMB) under the provisions of the
Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have
been assigned OMB Control Number 2120-0056.
(d) As of June 16, 1995 (the effective date of AD 95-11-13,
amendment 39-9246), no person shall install an aft mount beam
assembly, P/N 221-0261-501, on any airplane, unless it has been
previously inspected and re-identified in accordance with paragraph
3.B., Phase 2, of the Accomplishment Instructions of McDonnell
Douglas Alert Service Bulletin MD11-71A073, Revision 1, dated May
16, 1995.
(e) 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, Los Angeles ACO, FAA, Transport
Airplane Directorate. Operators shall submit their requests through
an appropriate FAA Principal Maintenance Inspector, who may
[[Page 32929]] add comments and then send it to the Manager, Los
Angeles ACO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
(f) 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 June 20, 1995.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 95-15517 Filed 6-23-95; 8:45 am]
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