AD 93-10-51
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | Pratt & Whitney Canada Corp. | 747-400 Series | Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 |
| aircraft | The Boeing Company | Pratt & Whitney Canada Corp. | Auxiliary Power Unit | Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 |
| appliance | The Boeing Company | Pratt & Whitney Canada Corp. | 747-400 Series | Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 |
| appliance | The Boeing Company | Pratt & Whitney Canada Corp. | Auxiliary Power Unit | Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 |
Unsafe Condition
APU gear failure can result in smoke contamination of aircraft passenger cabins.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Disassemble the APU load gearbox and remove the scavenge pump oil strainer element, Part No. 3107647-01. Reassemble the gearbox, reinstalling the existing chip detector and adapter. Inspect the magnetic chip detectors in accordance with the aircraft maintenance manual and thereafter at intervals not exceeding 150 APU operating hours.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 10 APU hours, or 5 days after the effective date of this airworthiness directive, whichever occurs first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Pratt & Whitney Canada APU Model PW901A, Part No. 3910001, installed on but not limited to Boeing Model 747-400 aircraft.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Auxiliary Power Unit
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_93-10-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-10-51 Document Type: AD Final Rules Docket Number: 93-ANE-33 Subject Heading: Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 Subject: Auxiliary Power Unit Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/10/1993 Make: The Boeing Company | Pratt & Whitney Canada Corp. Model: 747-400 Series | Auxiliary Power Unit Product Type: Appliance Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 93-10-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 93-ANE-33 AMENDMENT: 39-8604 AD NUMBER: 93-10-51 SUBJECT HEADING: Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 ACTION: SUMMARY: DATES: Effective August 10, 1993. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-10-51 PRATT & WHITNEY CANADA: Amendment 39-8604. Docket 93-ANE-33. Applicability: Pratt & Whitney Canada (P&WC) auxiliary power unit (APU) Model PW901A, Part No. 3910001, installed on but not limited to Boeing Model 747-400 aircraft. Compliance: Required as indicated, unless accomplished previously. To prevent APU gear failure, which can result in smoke contamination of aircraft passenger cabins, accomplish the following: (a) Within 10 APU hours, or 5 days after the effective date of this airworthiness directive (AD), whichever occurs first, in accordance with P&WC Alert Service Bulletin No. A16159R1, dated May 12, 1993: (1) Disassemble the APU load gearbox and remove the scavenge pump oil strainer element, Part No. (P/N) 3107647-01; and (2) Reassemble APU load gearbox, reinstalling the existing chip detector, P/N 3910098-01, and adapter, P/N 3910242-01. (b) Within 10 APU operating hours, or 5 days after the effective date of this AD, whichever occurs first: (1) Inspect the APU load gearbox and accessory gear box magnetic chip detectors in accordance with the appropriate aircraft maintenance manual; and (2) Thereafter, inspect the chip detectors at intervals not to exceed 150 APU operating hours since the last inspection. (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, New York 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, New York 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 New York Aircraft Certification Office. (d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (e) The removal and inspections shall be done in accordance with the following alert service bulletin: Document No. Pages Date PWC No. A16159R1 1-4 May 12, 1993 Total pages: 4. 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 Pratt & Whitney Canada, 1000 Marie-Victorin, Longueil, Quebec, Canada J4G 1A1. 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. (f) This amendment becomes effective August 10, 1993, to all persons except those persons to whom it was made immediately effective by telegraphic AD T93-10-51, issued May 20, 1993, which contained the requirements of this amendment. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_93-10-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-10-51 Document Type: AD Final Rules Docket Number: 93-ANE-33 Subject Heading: Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 Subject: Auxiliary Power Unit Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/10/1993 Make: The Boeing Company | Pratt & Whitney Canada Corp. Model: 747-400 Series | Auxiliary Power Unit Product Type: Appliance Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 93-10-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 93-ANE-33 AMENDMENT: 39-8604 AD NUMBER: 93-10-51 SUBJECT HEADING: Airworthiness Directives; PRATT & WHITNEY CANADA Auxiliary Power Unit (APU) Model PW901A, Part No. 3910001 ACTION: SUMMARY: DATES: Effective August 10, 1993. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-10-51 PRATT & WHITNEY CANADA: Amendment 39-8604. Docket 93-ANE-33. Applicability: Pratt & Whitney Canada (P&WC) auxiliary power unit (APU) Model PW901A, Part No. 3910001, installed on but not limited to Boeing Model 747-400 aircraft. Compliance: Required as indicated, unless accomplished previously. To prevent APU gear failure, which can result in smoke contamination of aircraft passenger cabins, accomplish the following: (a) Within 10 APU hours, or 5 days after the effective date of this airworthiness directive (AD), whichever occurs first, in accordance with P&WC Alert Service Bulletin No. A16159R1, dated May 12, 1993: (1) Disassemble the APU load gearbox and remove the scavenge pump oil strainer element, Part No. (P/N) 3107647-01; and (2) Reassemble APU load gearbox, reinstalling the existing chip detector, P/N 3910098-01, and adapter, P/N 3910242-01. (b) Within 10 APU operating hours, or 5 days after the effective date of this AD, whichever occurs first: (1) Inspect the APU load gearbox and accessory gear box magnetic chip detectors in accordance with the appropriate aircraft maintenance manual; and (2) Thereafter, inspect the chip detectors at intervals not to exceed 150 APU operating hours since the last inspection. (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, New York 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, New York 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 New York Aircraft Certification Office. (d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (e) The removal and inspections shall be done in accordance with the following alert service bulletin: Document No. Pages Date PWC No. A16159R1 1-4 May 12, 1993 Total pages: 4. 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 Pratt & Whitney Canada, 1000 Marie-Victorin, Longueil, Quebec, Canada J4G 1A1. 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. (f) This amendment becomes effective August 10, 1993, to all persons except those persons to whom it was made immediately effective by telegraphic AD T93-10-51, issued May 20, 1993, which contained the requirements of this amendment. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.