|
99-12-03
|
|||
|
Effective
Date - 07/08/1999 Applicability:
Note
1: This airworthiness directive (AD) applies to each engine 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 engines 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 (c) 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. To
prevent critical life-limited rotating engine part failure, which could
result in an uncontained engine failure and damage to the airplane, accomplish
the following: (a)
Within the next 30 days after the effective date of this AD, revise the
Time Limits Section (TLS) of the Pratt & Whitney (PW) JT8D-1, -1A,
-1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R, and -17AR
Turbofan Engines Engine Manual (EM), part number 481672, and for air carrier
operations revise the approved continuous airworthiness maintenance program,
by adding the following: 5.
Critical Life Limited Part Inspection A.
Inspection Requirements: (1)
This section has the definitions for individual engine piece parts and
the inspection procedures which are necessary when these parts are removed
from the engine. (2)
It is necessary to do the inspection procedures of the piece parts in
paragraph B when: (a)
The part is removed from the engine and disassembled to the level specified
in paragraph B and (b)
The part has accumulated more than 100 cycles since the last piece part
inspection, provided that the part was not damaged or related to the cause
for its removal from the engine. (3)
The inspections specified in this paragraph do not replace or make not
necessary other recommended inspections for these parts or other parts. B.
Parts Requiring Inspection Note:
Piece part is defined as any of the listed parts with all the blades removed. ------------------------------------------------------------------------
Engine manual description
Section Inspection ------------------------------------------------------------------------ Hub
(Disk), 1st Stage Compressor:
491201......................... 72-33-31 -04,-02,-03
496501......................... 72-33-31 -04,-02,-03
504101......................... 72-33-31 -04,-02,-03
515201......................... 72-33-31 -04,-02,-03
594301......................... 72-33-31 -04,-02,-03
640501......................... 72-33-31 -04,-02,-03
640601......................... 72-33-31 -04,-02,-03
743301......................... 72-33-31 -04,-02,-03
749701......................... 72-33-31 -04,-02,-03
749801......................... 72-33-31 -04,-02,-03
750001......................... 72-33-31 -04,-02,-03
750101......................... 72-33-31 -04,-02,-03
778901......................... 72-33-31 -04,-02,-03
791401......................... 72-33-31 -04,-02,-03
791501......................... 72-33-31 -04,-02,-03
791601......................... 72-33-31 -04,-02,-03
791701......................... 72-33-31 -04,-02,-03
791801......................... 72-33-31 -04,-02,-03
806001......................... 72-33-31 -04,-02,-03
806101......................... 72-33-31 -04,-02,-03
817401......................... 72-33-31 -04,-02,-03
844401......................... 72-33-31 -04,-02,-03
845401......................... 72-33-31 -04,-02,-03
848001......................... 72-33-31 -04,-02,-03
848101......................... 72-33-31 -04,-02,-03 Disk,
2nd Stage Compressor:
482502......................... 72-33-33 -02
502502......................... 72-33-33 -02
520602......................... 72-33-33 -02
570302......................... 72-33-33 -02
570402......................... 72-33-33 -02
678202......................... 72-33-33 -02
730202......................... 72-33-33 -02
730302......................... 72-33-33 -02
730402......................... 72-33-33 -02
740502......................... 72-33-33 -02
745702......................... 72-33-33 -02
745902......................... 72-33-33 -02
746002......................... 72-33-33 -02
746802......................... 72-33-33 -02
760402......................... 72-33-33 -02
760502......................... 72-33-33 -02
807502......................... 72-33-33 -02
5002402-01..................... 72-33-33 -02
790832 (Disk assembly)......... 72-33-33 -02 ------------------------------------------------------------------------ (b)
Except as provided in paragraph (c) of this AD, and notwithstanding contrary
provisions in section 43.16 of the Federal Aviation Regulations (14 CFR
43.16), these mandatory inspections shall be performed only in accordance
with the Time Limits section in the EM. (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 Engine Certification Office. Operators shall submit their requests
through an appropriate FAA Principal Maintenance Inspector (PMI), who
may add comments and then send it to the Engine Certification Office. Note
2: Information concerning the existence of approved alternative methods
of compliance with this airworthiness directive, if any, may be obtained
from the Engine Certification Office. (d)
Special flight permits may be used in accordance with Sec. 21.197 and
Sec. 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199)
to operate the airplane to a location where the requirement of this AD
can be accomplished. (e)
FAA-certificated air carriers that have an approved continuous airworthiness
maintenance program in accordance with the record keeping requirement
of Sec. 121.369(c) of the Federal Aviation Regulations [14 CFR 121.369(c)]
of this chapter must maintain records of the mandatory inspections that
result from revising the Time Limits section of the Instructions for Continuous
Airworthiness (ICA) and the air carrier's continuous airworthiness program.
Alternatively, certificated air carriers may establish an approved system
of record retention that provides a method for preservation and retrieval
of the maintenance records that include the inspections resulting from
this AD, and include the policy and procedures for implementing this alternative
method in the air carrier's maintenance manual required by Sec. 121.369(c)
of the Federal Aviation Regulations [14 CFR 121.369(c)]; however, the
alternative system must be accepted by the appropriate PMI and require
the maintenance records be maintained either indefinitely or until the
work is repeated. Records of the piece-part inspections are not required
under Sec. 121.380 (a)(2)(vi) of the Federal Aviation Regulations [14
CFR 121.380(a)(2)(vi)]. All other Operators must maintain the records
of mandatory inspections required by the applicable regulations governing
their operations. Note
3: The requirements of this AD have been met when the engine manual changes
are made and air carriers have modified their continuous airworthiness
maintenance plans to reflect the requirements in the engine manuals. (f)
This amendment becomes effective on July 8, 1999. FOR
FURTHER INFORMATION CONTACT: Christopher Spinney, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-7175,
fax (781) 238-7199. |
|||