AD 96-18-17

final rule

Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units

AD Number
96-18-17
Status
final_rule
Effective Date
Product Category
appliance
Docket
95-ANE-68
FR Citation
Federal Register: October 9, 1996 (Volume 61 Number 197))
Technical illustration of an aircraft turbine engine assembly
Problem area Engine

Applicability

TypeManufacturerModelDetails
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B2-1A Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B2-1C Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B2-203 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B2K-3C Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B4-103 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B4-203 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B4-2C Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B4-601 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B4-603 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
aircraft Airbus | AlliedSignal Inc | The Boeing Company A300 B4-605R Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B2-1A Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B2-1C Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B2-203 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B2K-3C Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-103 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-203 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-2C Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-601 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-603 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-605R Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-620 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-622 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 B4-622R Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 C4-605R Variant F Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 F4-605R Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company A300 F4-622R Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company Auxiliary Power Units Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company DC-10-10 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company DC-10-10F Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company DC-10-15 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company DC-10-30 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company DC-10-30F (KC-10A, KDC-10) Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company DC-10-40 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company DC-10-40F Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company MD-11 Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
appliance Airbus | AlliedSignal Inc | The Boeing Company MD-11F Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units

Unsafe Condition

Material defect in certain high pressure turbine (HPT) disk forgings may result in HPT disk rupture prior to reaching the disk cyclic life limit.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Remove from service affected HPT disks identified by serial number in AlliedSignal Aerospace SB No. TSCP700-49-A7168 and replace with serviceable parts. Actions must be done in accordance with the specified service bulletin.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Prior to accumulating 7,500 cycles since new (CSN), or 3 years after the effective date of this AD, whichever occurs first.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units (APUs) with HPT disks serial numbers listed in AlliedSignal Aerospace SB No. TSCP700-49-A7168, installed on Airbus A300 series, McDonnell Douglas DC-10, KC-10, and MD-11 series aircraft.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Auxiliary Power Units

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_96-18-17.html
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AD Number:
96-18-17
Document Type:
AD Final Rules
Docket Number:
95-ANE-68
Subject Heading:
Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
Subject:
Auxiliary Power Units
Status:
Current
Citation:
Federal Register: October 9, 1996 (Volume 61 Number 197))
Citation Publish Date:
10/09/1996
Effective Date:
12/09/1996
Make:
Airbus | AlliedSignal Inc | The Boeing Company
Model:
A300 B2-1A | A300 B2-1C | A300 B2-203 | A300 B2K-3C | A300 B4-103 | A300 B4-203 | A300 B4-2C | A300 ...Show more
Product Type:
Appliance
Product Subtype:
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39 (61 FR 52876 NO. 197 10/09/96)
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 96-18-17
CITATION:   Federal Register: October 9, 1996 (Volume 61 Number 197)]

PAGE NUMBER:   [Page 52876]

DOCKET NUMBER:   95-ANE-68

AMENDMENT:   39-9743

AD NUMBER:   96-18-17

SUBJECT HEADING:   Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units

ACTION:   Final rule.

SUMMARY:   This amendment adopts a new airworthiness directive (AD), applicable to AlliedSignal Inc. (formerly Garrett) TSCP700-4B, -4E, and -5 auxiliary power units (APUs), that requires removal from service of certain high pressure turbine (HPT) disks identified by serial number, and replacement with serviceable parts. This amendment is prompted by the discovery of a material defect in certain HPT disk forgings that may result in HPT disk rupture prior to reaching the disk cyclic life limit. The actions specified by this AD are intended to prevent an HPT disk rupture.

DATES:   Effective December 9, 1996. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of December 9, 1996.

ADDRESSES:   The service information referenced in this AD may be obtained from AlliedSignal Engines, P.O. Box 52181, Phoenix, AZ 85072-2181; telephone (800) 338-3378, fax (602) 231-4402. This information may be examined at the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:   Robert Baitoo, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone (310) 627-5245; fax (310) 627-5210.

SUPPLEMENTARY INFORMATION:   A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to AlliedSignal Inc. (formerly Garrett) Models TSCP700-4B, -4E, and -5 auxiliary power units (APUs) was published in the Federal Register on March 26, 1996 (61 FR 13113). That action proposed to require removal from service of certain high pressure turbine (HPT) disks identified by serial number, and replacement with serviceable parts, prior to accumulating 7,500 cycles since new (CSN), or 3 years after the effective date of this AD, whichever occurs first. The actions are required to be accomplished in accordance with AlliedSignal Aerospace Service Bulletin (SB) No. TSCP700-49-A7168, dated November 7, 1995.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Four commenters support the rule as proposed.

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 as proposed.

There are approximately 31 APUs of the affected design in the worldwide fleet. The FAA estimates that 20 APUs installed on aircraft of U.S. registry will be affected by this AD, that it will take no additional work hours if the disk is replaced during overhaul. The manufacturer has advised the FAA that they will supply required parts at no charge to the operator. The FAA has therefore determined that this AD will impose no additional cost on U.S. operators.

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, 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 USC 106(g), 40113, 44701.

§39.13 - [AMENDED]
2. Section 39.13 is amended by adding the following new airworthiness directive:

REGULATORY TEXT:  
96-18-17 ALLIEDSIGNAL INC.: Amendment 39-9743. Docket 95-ANE-68.

Applicability: AlliedSignal Inc. (formerly Garrett) Models TSCP700-4B, -4E, and -5 auxiliary power units (APUs), with high pressure turbine (HPT) disks identified by serial number in AlliedSignal Aerospace Service Bulletin (SB) No. TSCP700-49-A7168, dated November 7, 1995. These APUs are installed on, but not limited to, McDonnell Douglas DC-10, KC-10 (military), and MD-11 series, and Airbus A300 series aircraft.

Note: This airworthiness directive (AD) applies to each APU 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 APUs 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 (d) 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 an HPT disk rupture, accomplish the following:

(a) Prior to accumulating 7,500 cycles since new (CSN), or 3 years after the effective date of this AD, whichever occurs first, remove from service affected HPT disks and replace with a serviceable part.

(b) The definition of a disk cycle may be found in the applicable AlliedSignal Inc. APU Component Maintenance Manual.

(c) Auxiliary power unit maintenance records may be used to determine if the HPT disk installed in the APU has a serial number listed in AlliedSignal Aerospace SB No. TSCP700-49-A7168, dated November 7, 1995.

(d) 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 Aircraft Certification Office. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles Aircraft Certification Office.

Note: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Los Angeles Aircraft Certification Office.

(e) 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 aircraft to a location where the requirements of this AD can be accomplished.

(f) The actions required by this AD shall be done in accordance with the following AlliedSignal Aerospace SB:

Document No	Pages	Date
TSCP700-49-A7168	1-8	November 7, 1995
Total Pages: 8.		
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 AlliedSignal Engines, P.O. Box 52181, Phoenix, AZ 85072-2181; telephone (800) 338-3378, fax (602) 231-4402. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street NW., suite 700, Washington, DC.

(g) This amendment becomes effective on December 9, 1996.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_96-18-17.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
96-18-17
Document Type:
AD Final Rules
Docket Number:
95-ANE-68
Subject Heading:
Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units
Subject:
Auxiliary Power Units
Status:
Current
Citation:
Federal Register: October 9, 1996 (Volume 61 Number 197))
Citation Publish Date:
10/09/1996
Effective Date:
12/09/1996
Make:
Airbus | AlliedSignal Inc | The Boeing Company
Model:
A300 B2-1A | A300 B2-1C | A300 B2-203 | A300 B2K-3C | A300 B4-103 | A300 B4-203 | A300 B4-2C | A300 ...Show more
Product Type:
Appliance
Product Subtype:
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39 (61 FR 52876 NO. 197 10/09/96)
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 96-18-17
CITATION:   Federal Register: October 9, 1996 (Volume 61 Number 197)]

PAGE NUMBER:   [Page 52876]

DOCKET NUMBER:   95-ANE-68

AMENDMENT:   39-9743

AD NUMBER:   96-18-17

SUBJECT HEADING:   Airworthiness Directives; AlliedSignal Inc. TSCP700-4B, -4E, and -5 Auxiliary Power Units

ACTION:   Final rule.

SUMMARY:   This amendment adopts a new airworthiness directive (AD), applicable to AlliedSignal Inc. (formerly Garrett) TSCP700-4B, -4E, and -5 auxiliary power units (APUs), that requires removal from service of certain high pressure turbine (HPT) disks identified by serial number, and replacement with serviceable parts. This amendment is prompted by the discovery of a material defect in certain HPT disk forgings that may result in HPT disk rupture prior to reaching the disk cyclic life limit. The actions specified by this AD are intended to prevent an HPT disk rupture.

DATES:   Effective December 9, 1996. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of December 9, 1996.

ADDRESSES:   The service information referenced in this AD may be obtained from AlliedSignal Engines, P.O. Box 52181, Phoenix, AZ 85072-2181; telephone (800) 338-3378, fax (602) 231-4402. This information may be examined at the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:   Robert Baitoo, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone (310) 627-5245; fax (310) 627-5210.

SUPPLEMENTARY INFORMATION:   A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to AlliedSignal Inc. (formerly Garrett) Models TSCP700-4B, -4E, and -5 auxiliary power units (APUs) was published in the Federal Register on March 26, 1996 (61 FR 13113). That action proposed to require removal from service of certain high pressure turbine (HPT) disks identified by serial number, and replacement with serviceable parts, prior to accumulating 7,500 cycles since new (CSN), or 3 years after the effective date of this AD, whichever occurs first. The actions are required to be accomplished in accordance with AlliedSignal Aerospace Service Bulletin (SB) No. TSCP700-49-A7168, dated November 7, 1995.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Four commenters support the rule as proposed.

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 as proposed.

There are approximately 31 APUs of the affected design in the worldwide fleet. The FAA estimates that 20 APUs installed on aircraft of U.S. registry will be affected by this AD, that it will take no additional work hours if the disk is replaced during overhaul. The manufacturer has advised the FAA that they will supply required parts at no charge to the operator. The FAA has therefore determined that this AD will impose no additional cost on U.S. operators.

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, 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 USC 106(g), 40113, 44701.

§39.13 - [AMENDED]
2. Section 39.13 is amended by adding the following new airworthiness directive:

REGULATORY TEXT:  
96-18-17 ALLIEDSIGNAL INC.: Amendment 39-9743. Docket 95-ANE-68.

Applicability: AlliedSignal Inc. (formerly Garrett) Models TSCP700-4B, -4E, and -5 auxiliary power units (APUs), with high pressure turbine (HPT) disks identified by serial number in AlliedSignal Aerospace Service Bulletin (SB) No. TSCP700-49-A7168, dated November 7, 1995. These APUs are installed on, but not limited to, McDonnell Douglas DC-10, KC-10 (military), and MD-11 series, and Airbus A300 series aircraft.

Note: This airworthiness directive (AD) applies to each APU 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 APUs 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 (d) 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 an HPT disk rupture, accomplish the following:

(a) Prior to accumulating 7,500 cycles since new (CSN), or 3 years after the effective date of this AD, whichever occurs first, remove from service affected HPT disks and replace with a serviceable part.

(b) The definition of a disk cycle may be found in the applicable AlliedSignal Inc. APU Component Maintenance Manual.

(c) Auxiliary power unit maintenance records may be used to determine if the HPT disk installed in the APU has a serial number listed in AlliedSignal Aerospace SB No. TSCP700-49-A7168, dated November 7, 1995.

(d) 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 Aircraft Certification Office. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles Aircraft Certification Office.

Note: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Los Angeles Aircraft Certification Office.

(e) 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 aircraft to a location where the requirements of this AD can be accomplished.

(f) The actions required by this AD shall be done in accordance with the following AlliedSignal Aerospace SB:

Document No	Pages	Date
TSCP700-49-A7168	1-8	November 7, 1995
Total Pages: 8.		
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 AlliedSignal Engines, P.O. Box 52181, Phoenix, AZ 85072-2181; telephone (800) 338-3378, fax (602) 231-4402. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street NW., suite 700, Washington, DC.

(g) This amendment becomes effective on December 9, 1996.

FOOTER:

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