AD 72-16-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | MD Helicopters, Inc. | 369A | Airworthiness Directives; Hughes Model 369A and 369H Series Helicopters |
| aircraft | MD Helicopters, Inc. | 369H | Airworthiness Directives; Hughes Model 369A and 369H Series Helicopters |
Unsafe Condition
Failure of the tail rotor input gearshaft assembly due to finite life limits (1,800 hours) for part numbers 369A5406 (input only), 369A5425, and -3, and 27,600 hours for P/N 369A5425-5.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise helicopter logbook entries per Hughes Service Information Notice No. HN-53 Part I and retire/replace input gearshaft assemblies per Part II of the same notice. Compliance must be completed prior to further flight or within 100 additional hours of time in service, depending on current time in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Prior to further flight if the gearshaft has 2,000 hours or more time in service, or within 100 additional time in service if between 1,800 and 2,000 hours, adjusted to prevent exceeding 2,000 hours.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
MD Helicopters, Inc. Models 369A and 369H Series Helicopters with tail rotor input gearshaft assemblies (P/N 369A5406, 369A5425, -3, or -5).
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Tail rotor input gear shaft assys
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_72-16-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-16-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hughes Model 369A and 369H Series Helicopters Subject: Tail rotor input gear shaft assys Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/08/1972 Make: MD Helicopters, Inc. Model: 369A | 369H Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 72-16-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1497 AD NUMBER: 72-16-09 SUBJECT HEADING: Airworthiness Directives; Hughes Model 369A and 369H Series Helicopters ACTION: SUMMARY: DATES: Effective August 8, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-16-09 HUGHES: Amendment 39-1497. Applies to Hughes Model 369A and 369H Series Helicopters certificated in all categories. Compliance required as indicated. To prevent possible failure of the input gearshaft assembly, accomplish the following: (a) For those helicopters incorporating tail rotor input gearshaft assemblies (see NOTE for P/N's) which have accumulated 2,000 hours' or more time in service on the effective date of this AD, accomplish (c) and (d), below, unless already accomplished, prior to further flight. (b) For those helicopters incorporating tail rotor input gearshaft assemblies (see NOTE for P/N's) which have accumulated 1,800 hours' or more time in service on the effective date of this AD, accomplish (c) and (d), below, within 100 additional time in service, unless already accomplished. If the additional time in service would result in a total time in service in excess of 2000 hours, the 100 hours' compliance time shall be reduced by that amount necessary to prevent any tail rotor input gearshaft assemblies from being operated beyond 2000 hours before accomplishment of this AD. (c) Revise the helicopter logbook, as applicable, to record both the input and the output gearshaft assemblies incorporated in the 369A5406 tail rotor gear set, per the instructions of Part I of Hughes Service Information Notice No. HN-53, dated July 24, 1972, or later FAA approved revisions. (d) Retire and replace the 369A5425 and 369A5425-3 input gearshaft assemblies (input part of 369A5406 gearset), per the instructions of Part II of Hughes Service Information Notice No. HN-53, dated July 24, 1972, or later FAA approved revisions. Owners and operators may exercise the options specified in Part II of the Notice. NOTE: The part number assemblies and finite life are: TAIL ROTOR INPUT FINITE GEARSHAFT ASSEMBLY LIFE P/N 369A5406 (input only) 1,800 hours P/N 369A5425, -3 1,800 hours P/N 369A5425-5 27,600 hours NOTE: The P/N 369A5406 tail rotor gearset is comprised of an input gearshaft assembly and a pinion output gearshaft assembly. The finite life of all existing pinion output gearshaft assemblies remains unchanged at 2,940 hours. This amendment becomes effective August 8, 1972. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_72-16-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-16-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hughes Model 369A and 369H Series Helicopters Subject: Tail rotor input gear shaft assys Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/08/1972 Make: MD Helicopters, Inc. Model: 369A | 369H Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 72-16-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1497 AD NUMBER: 72-16-09 SUBJECT HEADING: Airworthiness Directives; Hughes Model 369A and 369H Series Helicopters ACTION: SUMMARY: DATES: Effective August 8, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-16-09 HUGHES: Amendment 39-1497. Applies to Hughes Model 369A and 369H Series Helicopters certificated in all categories. Compliance required as indicated. To prevent possible failure of the input gearshaft assembly, accomplish the following: (a) For those helicopters incorporating tail rotor input gearshaft assemblies (see NOTE for P/N's) which have accumulated 2,000 hours' or more time in service on the effective date of this AD, accomplish (c) and (d), below, unless already accomplished, prior to further flight. (b) For those helicopters incorporating tail rotor input gearshaft assemblies (see NOTE for P/N's) which have accumulated 1,800 hours' or more time in service on the effective date of this AD, accomplish (c) and (d), below, within 100 additional time in service, unless already accomplished. If the additional time in service would result in a total time in service in excess of 2000 hours, the 100 hours' compliance time shall be reduced by that amount necessary to prevent any tail rotor input gearshaft assemblies from being operated beyond 2000 hours before accomplishment of this AD. (c) Revise the helicopter logbook, as applicable, to record both the input and the output gearshaft assemblies incorporated in the 369A5406 tail rotor gear set, per the instructions of Part I of Hughes Service Information Notice No. HN-53, dated July 24, 1972, or later FAA approved revisions. (d) Retire and replace the 369A5425 and 369A5425-3 input gearshaft assemblies (input part of 369A5406 gearset), per the instructions of Part II of Hughes Service Information Notice No. HN-53, dated July 24, 1972, or later FAA approved revisions. Owners and operators may exercise the options specified in Part II of the Notice. NOTE: The part number assemblies and finite life are: TAIL ROTOR INPUT FINITE GEARSHAFT ASSEMBLY LIFE P/N 369A5406 (input only) 1,800 hours P/N 369A5425, -3 1,800 hours P/N 369A5425-5 27,600 hours NOTE: The P/N 369A5406 tail rotor gearset is comprised of an input gearshaft assembly and a pinion output gearshaft assembly. The finite life of all existing pinion output gearshaft assemblies remains unchanged at 2,940 hours. This amendment becomes effective August 8, 1972. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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