AD 68-06-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | FH1100 Manufacturing Corporation | FH-1100 | Airworthiness Directives; Fairchild-Hiller Model FH-1100 Helicopters |
Unsafe Condition
Failure of the engine-to-transmission coupling shaft due to corrosion resulting from water contamination.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove Bendix coupling shaft P/N 19E49-3A, inspect for corrosion. If corrosion is found, replace with P/N 19E49-3B; if absent, modify per Fairchild Hiller Service Bulletin No. FH-1100-24-1 or equivalent procedure approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 100 helicopter hours' time in service following the effective date of this AD
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Affected Aircraft
Fairchild-Hiller Model FH-1100 helicopters, serial numbers 10 thru 76 inclusive and 83.
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Federal Register Abstract
Failure of Coupling Shaft
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_68-06-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-06-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild-Hiller Model FH-1100 Helicopters Subject: Failure of Coupling Shaft Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/23/1968 Make: FH1100 Manufacturing Corporation Model: FH-1100 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 68-06-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-565 AD NUMBER: 68-06-05 SUBJECT HEADING: Airworthiness Directives; Fairchild-Hiller Model FH-1100 Helicopters ACTION: SUMMARY: DATES: Effective March 23, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-06-05 FAIRCHILD-HILLER: Amdt. 39-565. Applies to FH-1100 type helicopters serial numbers 10 thru 76 inclusive and 83. Compliance required as indicated unless already accomplished. To preclude the possibility of failure of the engine-to-transmission coupling shaft due to corrosion resulting from water contamination, accomplish the following: (a) Within the next 100 helicopter hours' time in service following the effective date of this AD, remove Bendix coupling shaft P/N 19E49-3A and inspect for any corrosion and if found, replace with P/N 19E49-3B or if corrosion is absent modify in accordance with accomplishment instructions contained in Fairchild Hiller Service Bulletin No. FH-1100-24-1 dated January 25, 1968, or later FAA approved revision, or an equivalent inspection procedure or modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (b) Upon request, with substantiating data submitted through an FAA maintenance inspector, the compliance time may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. This amendment is effective March 23, 1968. FOOTER:
Document Text
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AD Final Rules - DRS_68-06-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-06-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild-Hiller Model FH-1100 Helicopters Subject: Failure of Coupling Shaft Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/23/1968 Make: FH1100 Manufacturing Corporation Model: FH-1100 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: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 68-06-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-565 AD NUMBER: 68-06-05 SUBJECT HEADING: Airworthiness Directives; Fairchild-Hiller Model FH-1100 Helicopters ACTION: SUMMARY: DATES: Effective March 23, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-06-05 FAIRCHILD-HILLER: Amdt. 39-565. Applies to FH-1100 type helicopters serial numbers 10 thru 76 inclusive and 83. Compliance required as indicated unless already accomplished. To preclude the possibility of failure of the engine-to-transmission coupling shaft due to corrosion resulting from water contamination, accomplish the following: (a) Within the next 100 helicopter hours' time in service following the effective date of this AD, remove Bendix coupling shaft P/N 19E49-3A and inspect for any corrosion and if found, replace with P/N 19E49-3B or if corrosion is absent modify in accordance with accomplishment instructions contained in Fairchild Hiller Service Bulletin No. FH-1100-24-1 dated January 25, 1968, or later FAA approved revision, or an equivalent inspection procedure or modification approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (b) Upon request, with substantiating data submitted through an FAA maintenance inspector, the compliance time may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. This amendment is effective March 23, 1968. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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