AD 81-17-04

final rule

Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters

AD Number
81-17-04
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft Schweizer Aircraft Corporation 269A Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters
aircraft Schweizer Aircraft Corporation 269A-1 Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters
aircraft Schweizer Aircraft Corporation 269B Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters
aircraft Schweizer Aircraft Corporation 269C Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters

Unsafe Condition

Failure of the main transmission due to cracks, fretting, or other stress risers in the main rotor ring gear drive shaft assemblies with P/Ns 269A5179, 269A5179-3, or unmodified P/N 269A5179.

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

Required Actions

Inspect shaft and coupling assembly lower bearing bore and fasteners for cracks, fretting, or stress risers per Hughes Service Notice N-179. Replace with P/N 269A5194 assembly reworked per N-142.1 if issues found. Perform recurring inspections at specified intervals or replace assemblies with P/N 269A5194 within specified compliance times.

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

Compliance Time

Within 100 hours' additional time in service from the effective date or 600 hours total time in service, whichever occurs later (for paragraph (a)(1)), or within 100 hours' additional time in service from the effective date or 2,000/2,500 hours total time in service depending on model (for paragraph (a)(2)), or within 25 hours' additional time in service after the effective date, 400 hours' total time, or 300 hours since last inspection (for paragraph (b)), with subsequent intervals not exceeding 300 or 500 hours as specified.

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

Affected Aircraft

Schweizer Aircraft Corporation Model 269A, 269A-1, 269B, 269C helicopters and TH-55s with P/Ns 269A5179, 269A5179-3 Drive Shaft Coupling Assemblies or unmodified P/N 269A5179 Ring Gear Carrier Assembly.

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

Federal Register Abstract

Drive Shaft Assemblies

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_81-17-04.html
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AD Number:
81-17-04
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters
Subject:
Drive Shaft Assemblies
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/24/1981
Make:
Schweizer Aircraft Corporation
Model:
269A | 269A-1 | 269B | 269C
Product Type:
Aircraft
Product Subtype:
Glider
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
Updated RGL applicability to match AD applicability; CAR C-11-185
AIRWORTHINESS DIRECTIVES FINAL RULES: 81-17-04
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4185

AD NUMBER:   81-17-04

SUBJECT HEADING:   Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective August 24, 1981.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
81-17-04 HUGHES HELICOPTERS: Amendment 39-4185. Applies to Model 269 helicopters, all models, and TH-55s, certified in all categories, incorporating P/Ns 269A5179 or 269A5179-3 Drive Shaft Coupling Assemblies, and those helicopters incorporating the improved P/N 269A5194 Ring Gear Carrier Assembly.

Compliance required as indicated, unless already accomplished.

To prevent failure of the main transmission, accomplish the following:

(a) For main rotor ring gear driveshaft assemblies, P/N 269A5179 or 269A5179-3:

(1) Within 100 hours' additional time in service from the effective date of this AD, or 600 hours total time in service, whichever occurs later, inspect shaft and coupling assembly lower bearing bore and fasteners for evidence of cracks, fretting, or other stress risers, in accordance with Part IIA and IIB of Hughes Service Notice No. N-179 dated July 17, 1981. If cracks, fretting or stress risers are found, replace with P/N 269A5194 assembly reworked per Hughes Notice No. N142.1, prior to further flight.

(2) Within 100 hours' additional time in service from the effective date of this AD, or 2,000 hours total time in service for 269C aircraft or 2,500 hours total time in service for 269A/A-1/B/TH-55A aircraft, whichever occurs later, remove and replace shaft and coupling assembly with 269A5194 ring gear carrier assembly reworked per Hughes Notice No. N-142.1 dated May 31, 1977.

(b) For main rotor ring gear drive shaft assemblies, P/N 269A5179 not modified per Hughes Notice No. N-114-3 dated September 19, 1977:

Within the next 25 hours' additional time in service after the effective date of this AD, or 400 hours' total time in service, or 300 hours since the last inspection performed per paragraph (a) of AD 77-21-10, whichever occurs later, and at intervals not to exceed 300 hours' time in service thereafter, perform a close visual inspection and penetrant inspection of shaft and coupling fastener area per Part IIB of Hughes Notice No. N-179, for fretting, cracking, or other stress risers. If cracks, fretting or stress risers are found, replace with P/N 269A5194 assembly reworked per Hughes Notice No. N-142.1, prior to further flight.

(c) For main rotor ring gear drive shaft assemblies, P/N 269A5179 previously modified per Hughes Notice No. N-114.3 at or before the accumulation of 1000 hours' additional time in service since modification per Hughes Notice N-114.3, and at intervals not to exceed 500 hours' time in service thereafter, accomplish the visual and penetrant inspections of the fastener areas, as described in paragraph (b), above.

(d) The recurring inspections of paragraphs (b) and (c), above, may be discontinued when P/N 269A5194 assemblies are installed. The service life limit on P/N 269A5194 is 6,000 hours.

(e) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate aircraft to a base for the accomplishment of inspections or modifications required by this AD.

(f) Alternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Engineering and Manufacturing Branch, FAA Western Region.

The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive, who have not already received these documents from the manufacturer, may obtain copies upon request to Hughes Helicopters, Inc., Centinela and Teale Street, Culver City, California 90230. These documents may also be examined at FAA Western Region Office, 15000 Aviation Boulevard, Hawthorne, California 90261 and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591. A historical file on this AD, which includes the incorporated material in full, is maintained by the FAA at its Headquarters in Washington, D.C. and at FAA Western Region Office.

This supersedes Amendment 39-3060 (42 FR 55882), AD 77-21-10.
This amendment becomes effective August 24, 1981.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_81-17-04.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
81-17-04
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters
Subject:
Drive Shaft Assemblies
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/24/1981
Make:
Schweizer Aircraft Corporation
Model:
269A | 269A-1 | 269B | 269C
Product Type:
Aircraft
Product Subtype:
Glider
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
Updated RGL applicability to match AD applicability; CAR C-11-185
AIRWORTHINESS DIRECTIVES FINAL RULES: 81-17-04
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4185

AD NUMBER:   81-17-04

SUBJECT HEADING:   Airworthiness Directives; HUGHES HELICOPTERS Model 269 Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective August 24, 1981.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
81-17-04 HUGHES HELICOPTERS: Amendment 39-4185. Applies to Model 269 helicopters, all models, and TH-55s, certified in all categories, incorporating P/Ns 269A5179 or 269A5179-3 Drive Shaft Coupling Assemblies, and those helicopters incorporating the improved P/N 269A5194 Ring Gear Carrier Assembly.

Compliance required as indicated, unless already accomplished.

To prevent failure of the main transmission, accomplish the following:

(a) For main rotor ring gear driveshaft assemblies, P/N 269A5179 or 269A5179-3:

(1) Within 100 hours' additional time in service from the effective date of this AD, or 600 hours total time in service, whichever occurs later, inspect shaft and coupling assembly lower bearing bore and fasteners for evidence of cracks, fretting, or other stress risers, in accordance with Part IIA and IIB of Hughes Service Notice No. N-179 dated July 17, 1981. If cracks, fretting or stress risers are found, replace with P/N 269A5194 assembly reworked per Hughes Notice No. N142.1, prior to further flight.

(2) Within 100 hours' additional time in service from the effective date of this AD, or 2,000 hours total time in service for 269C aircraft or 2,500 hours total time in service for 269A/A-1/B/TH-55A aircraft, whichever occurs later, remove and replace shaft and coupling assembly with 269A5194 ring gear carrier assembly reworked per Hughes Notice No. N-142.1 dated May 31, 1977.

(b) For main rotor ring gear drive shaft assemblies, P/N 269A5179 not modified per Hughes Notice No. N-114-3 dated September 19, 1977:

Within the next 25 hours' additional time in service after the effective date of this AD, or 400 hours' total time in service, or 300 hours since the last inspection performed per paragraph (a) of AD 77-21-10, whichever occurs later, and at intervals not to exceed 300 hours' time in service thereafter, perform a close visual inspection and penetrant inspection of shaft and coupling fastener area per Part IIB of Hughes Notice No. N-179, for fretting, cracking, or other stress risers. If cracks, fretting or stress risers are found, replace with P/N 269A5194 assembly reworked per Hughes Notice No. N-142.1, prior to further flight.

(c) For main rotor ring gear drive shaft assemblies, P/N 269A5179 previously modified per Hughes Notice No. N-114.3 at or before the accumulation of 1000 hours' additional time in service since modification per Hughes Notice N-114.3, and at intervals not to exceed 500 hours' time in service thereafter, accomplish the visual and penetrant inspections of the fastener areas, as described in paragraph (b), above.

(d) The recurring inspections of paragraphs (b) and (c), above, may be discontinued when P/N 269A5194 assemblies are installed. The service life limit on P/N 269A5194 is 6,000 hours.

(e) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate aircraft to a base for the accomplishment of inspections or modifications required by this AD.

(f) Alternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Engineering and Manufacturing Branch, FAA Western Region.

The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive, who have not already received these documents from the manufacturer, may obtain copies upon request to Hughes Helicopters, Inc., Centinela and Teale Street, Culver City, California 90230. These documents may also be examined at FAA Western Region Office, 15000 Aviation Boulevard, Hawthorne, California 90261 and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591. A historical file on this AD, which includes the incorporated material in full, is maintained by the FAA at its Headquarters in Washington, D.C. and at FAA Western Region Office.

This supersedes Amendment 39-3060 (42 FR 55882), AD 77-21-10.
This amendment becomes effective August 24, 1981.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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