AD 75-07-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Honeywell International Inc. | TFE731-2 | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-2A | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-2B | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-2BR | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-2C | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3 | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3A | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3AR | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3B | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3BR | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3C | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3CR | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3D | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3DR | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
| engine | Honeywell International Inc. | TFE731-3R | AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines |
Unsafe Condition
Wear of the transfer gearbox vertical bevel gear bearing support can result in failure of the accessory drive and contamination of the engine lubrication system.
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Required Actions
Inspect the lower shoulder of transfer gearbox vertical bearing support for wear and replace as required per AiResearch Service Bulletin TFE731-72-3019. The inspections may be discontinued if equipped with transfer gearbox assembly P/N 3070093-3 (Series I, Change 2 or Series 3) or after replacing bearing support P/N 3070217-1 with improved P/N 3070217-3 per Service Bulletin TFE731-72-3020.
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Compliance Time
Within the next 25 hours time in service after receipt of this Airworthiness Directive, and at intervals not to exceed 50 hours time in service thereafter.
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Affected Aircraft
AiResearch Manufacturing Company of Arizona Model TFE731-2 and -3 series engines.
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Federal Register Abstract
Transfer Gearbox Vertical Bevel Gear Bearing
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-07-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-07-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines Subject: Transfer Gearbox Vertical Bevel Gear Bearing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/01/1975 Make: Honeywell International Inc. Model: TFE731-2 | TFE731-2A | TFE731-2B | TFE731-2BR | TFE731-2C | TFE731-3 | TFE731-3A | TFE731-3AR | TFE7...Show more Product Type: Engine 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: 75-07-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2189 AD NUMBER: 75-07-10 SUBJECT HEADING: AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines ACTION: SUMMARY: DATES: Effective May 1, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-07-10 AIRESEARCH MANUFACTURING COMPANY of ARIZONA: Amendment 39-2144 as amended by Amendment 39-2189. Applies to AiResearch TFE731-2 and -3 series engines. Compliance required as indicated. To detect, prevent and correct wear of the transfer gearbox vertical bevel gear bearing support which can result in failure of the accessory drive and contamination of the engine lubrication system, accomplish the following: (A) Within the next 25 hours time in service after receipt of this Airworthiness Directive, unless previously accomplished, and at intervals not to exceed 50 hours time in service thereafter, inspect the lower shoulder of transfer gearbox vertical bearing support for wear and replacements as required per AiResearch Service Bulletin TFE731-72-3019, dated February 27, 1975, or later FAA-approved revisions. (B) The inspections required by paragraph (A) above, are not required if the engine is equipped with a transfer gearbox assembly, P/N 3070093-3, designated as Series I, Change 2 or Series 3, and may be discontinued on engines equipped with Series I Transfer Gearbox Assemblies when the bearing support, P/N 3070217-1, is replaced with an improved bearing support, P/N 3070217-3, per AiResearch Service Bulletin TFE731-72-3020, dated February 27, 1975, or later FAA-approved revisions. Bearing supports, P/N 3070217-1, which are removed from service shall be rendered unserviceable. (C) Equivalent procedures may be approved by the Chief, Aircraft Engineering Division, FAA Western Region, upon submission of adequate substantiating data. (D) Aircraft may be flown to a base for performance of maintenance required by this AD per FAR's 21.197 and 21.199. Amendment 39-2144 became effective April 3, 1975, for all persons except those to whom it was made effective by airmail letters dated February 28, 1975. This amendment 39-2189 becomes effective May 1, 1975. FOOTER:
Document Text
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AD Final Rules - DRS_75-07-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-07-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines Subject: Transfer Gearbox Vertical Bevel Gear Bearing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/01/1975 Make: Honeywell International Inc. Model: TFE731-2 | TFE731-2A | TFE731-2B | TFE731-2BR | TFE731-2C | TFE731-3 | TFE731-3A | TFE731-3AR | TFE7...Show more Product Type: Engine 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: 75-07-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2189 AD NUMBER: 75-07-10 SUBJECT HEADING: AIRESEARCH MANUFACTURING COMPANY of ARIZONA Model TFE731-2 and -3 Series Engines ACTION: SUMMARY: DATES: Effective May 1, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-07-10 AIRESEARCH MANUFACTURING COMPANY of ARIZONA: Amendment 39-2144 as amended by Amendment 39-2189. Applies to AiResearch TFE731-2 and -3 series engines. Compliance required as indicated. To detect, prevent and correct wear of the transfer gearbox vertical bevel gear bearing support which can result in failure of the accessory drive and contamination of the engine lubrication system, accomplish the following: (A) Within the next 25 hours time in service after receipt of this Airworthiness Directive, unless previously accomplished, and at intervals not to exceed 50 hours time in service thereafter, inspect the lower shoulder of transfer gearbox vertical bearing support for wear and replacements as required per AiResearch Service Bulletin TFE731-72-3019, dated February 27, 1975, or later FAA-approved revisions. (B) The inspections required by paragraph (A) above, are not required if the engine is equipped with a transfer gearbox assembly, P/N 3070093-3, designated as Series I, Change 2 or Series 3, and may be discontinued on engines equipped with Series I Transfer Gearbox Assemblies when the bearing support, P/N 3070217-1, is replaced with an improved bearing support, P/N 3070217-3, per AiResearch Service Bulletin TFE731-72-3020, dated February 27, 1975, or later FAA-approved revisions. Bearing supports, P/N 3070217-1, which are removed from service shall be rendered unserviceable. (C) Equivalent procedures may be approved by the Chief, Aircraft Engineering Division, FAA Western Region, upon submission of adequate substantiating data. (D) Aircraft may be flown to a base for performance of maintenance required by this AD per FAR's 21.197 and 21.199. Amendment 39-2144 became effective April 3, 1975, for all persons except those to whom it was made effective by airmail letters dated February 28, 1975. This amendment 39-2189 becomes effective May 1, 1975. FOOTER:
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