AD 70-04-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Honeywell International Inc. | TPE331-1 | AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines |
| engine | Honeywell International Inc. | TPE331-1U | AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines |
| engine | Honeywell International Inc. | TPE331-1UA | AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines |
| engine | Honeywell International Inc. | TPE331-2 | AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines |
| engine | Honeywell International Inc. | TPE331-2U | AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines |
| engine | Honeywell International Inc. | TPE331-2UA | AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines |
Unsafe Condition
Backing off of the high speed pinion retaining nut can cause a serious engine failure.
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Required Actions
Within 10 hours time in service, inspect the engine oil filter for metal particles and install a placard advising pilots to shut down the engine if there is an abrupt loss of torque indication. At each inspection, replace the filter and return the removed filter for laboratory examination. Within 150 hours time in service, rework or replace the high speed pinion gear shaft assembly per AiResearch Service Bulletin 587.
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Compliance Time
Within 10 hours time in service
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Affected Aircraft
Honeywell International Inc. Model TPE331-1 and -2 engines with serial numbers: 90005, 90009, 90010, 90011, 90014, 90016, 90017, 90018, 90019, 90022, 90023, 90024, 90027, 90028, 90029, 90030, 91003, 91004, 91005, 91006, 91009, 91011, 91013 thru 91021, 91023, 91024, 91025, 91027, 92001, 92002, 92003, 92004, 92005, 92007, 92010, 92012, 92013, 92014, 92016 thru 92027, 93007, 93008, 93009, 93010.
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Federal Register Abstract
High Speed Pinion Retaining Nut
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_70-04-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-04-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines Subject: High Speed Pinion Retaining Nut Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Honeywell International Inc. Model: TPE331-1 | TPE331-1U | TPE331-1UA | TPE331-2 | TPE331-2U | TPE331-2UA 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: 70-04-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-944 AD NUMBER: 70-04-04 SUBJECT HEADING: AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-04-04 AIRESEARCH: Amendment 39-944. Applies to Model TPE331-1 and -2 S/N engines: 90005, 90009, 90010, 90011, 90014, 90016, 90017, 90018, 90019, 90022, 90023, 90024, 90027, 90028, 90029, 90030, 91003, 91004, 91005, 91006, 91009, 91011, 91013 thru 91021, 91023, 91024, 91025, 91027, 92001, 92002, 92003, 92004, 92005, 92007, 92010, 92012, 92013, 92014, 92016, thru 92027, 93007, 93008, 93009, 93010; installed in but not limited to Mooney MU-2, Merlin 2B, Volpar Turboliner and Short Skyvan aircraft is effective upon receipt of this telegram. This directive necessary because of a serious engine failure caused by backing off of the high speed pinion retaining nut. To detect and prevent engine failure from this cause, the following is required: (A) Within 10 hours time in service unless previously accomplished within the last 15 hours time in service, and at intervals not to exceed 25 hours time in service thereafter, remove the engine oil filter and inspect the filter for metal particles. If an abnormal quantity of metal particles is found, accomplish Item (C) before further operation of the engine. At each inspection a replacement filter must be installed and the filter which was removed shall be returned for laboratory examination to AiResearch or to a facility approved by the Chief, Aircraft Engineering Division, Western Region. Any finding of unacceptable metal contamination by AiResearch or other approved facility will be communicated to the owner or operator and the FAA. Upon receipt of such notice the engine shall then not be operated until Item (C) is accomplished. 25 hours oil filter special inspections may be discontinued upon completion of Item (C). (B) Within 10 hours time in service, install a placard in full view of the pilot to read: 'If abrupt and complete loss of torque indication occurs, shut down the engine and determine the cause.' This placard may be removed when Item (C) is accomplished. (C) Within 150 hours time in service unless previously accomplished, rework or replace the high speed pinion gear shaft assembly, P/N 869337-2, -3, or -4, in accordance with AiResearch Service Bulletin No. 587, dated 5 February 1970, or later FAA approved revisions. This amendment is effective upon publication in the Federal Register for all person except those to whom it was made effective immediately by telegram dated February 5, 1970. FOOTER:
Document Text
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AD Final Rules - DRS_70-04-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-04-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines Subject: High Speed Pinion Retaining Nut Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Honeywell International Inc. Model: TPE331-1 | TPE331-1U | TPE331-1UA | TPE331-2 | TPE331-2U | TPE331-2UA 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: 70-04-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-944 AD NUMBER: 70-04-04 SUBJECT HEADING: AIRESEARCH Model TPE-331-1 and TPE-331-2 Engines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-04-04 AIRESEARCH: Amendment 39-944. Applies to Model TPE331-1 and -2 S/N engines: 90005, 90009, 90010, 90011, 90014, 90016, 90017, 90018, 90019, 90022, 90023, 90024, 90027, 90028, 90029, 90030, 91003, 91004, 91005, 91006, 91009, 91011, 91013 thru 91021, 91023, 91024, 91025, 91027, 92001, 92002, 92003, 92004, 92005, 92007, 92010, 92012, 92013, 92014, 92016, thru 92027, 93007, 93008, 93009, 93010; installed in but not limited to Mooney MU-2, Merlin 2B, Volpar Turboliner and Short Skyvan aircraft is effective upon receipt of this telegram. This directive necessary because of a serious engine failure caused by backing off of the high speed pinion retaining nut. To detect and prevent engine failure from this cause, the following is required: (A) Within 10 hours time in service unless previously accomplished within the last 15 hours time in service, and at intervals not to exceed 25 hours time in service thereafter, remove the engine oil filter and inspect the filter for metal particles. If an abnormal quantity of metal particles is found, accomplish Item (C) before further operation of the engine. At each inspection a replacement filter must be installed and the filter which was removed shall be returned for laboratory examination to AiResearch or to a facility approved by the Chief, Aircraft Engineering Division, Western Region. Any finding of unacceptable metal contamination by AiResearch or other approved facility will be communicated to the owner or operator and the FAA. Upon receipt of such notice the engine shall then not be operated until Item (C) is accomplished. 25 hours oil filter special inspections may be discontinued upon completion of Item (C). (B) Within 10 hours time in service, install a placard in full view of the pilot to read: 'If abrupt and complete loss of torque indication occurs, shut down the engine and determine the cause.' This placard may be removed when Item (C) is accomplished. (C) Within 150 hours time in service unless previously accomplished, rework or replace the high speed pinion gear shaft assembly, P/N 869337-2, -3, or -4, in accordance with AiResearch Service Bulletin No. 587, dated 5 February 1970, or later FAA approved revisions. This amendment is effective upon publication in the Federal Register for all person except those to whom it was made effective immediately by telegram dated February 5, 1970. FOOTER:
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