AD 71-24-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | FH1100 Manufacturing Corporation | 1100 | Airworthiness Directives; Fairchild Hiller Models 1100 and FH-1100 Helicopters |
| aircraft | FH1100 Manufacturing Corporation | FH-1100 | Airworthiness Directives; Fairchild Hiller Models 1100 and FH-1100 Helicopters |
Unsafe Condition
Fatigue failure of the transmission mount strut, P/N 24-28031, due to internal corrosion.
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Required Actions
Replace P/N 24-28031 left side, lateral, adjustable transmission strut with P/N 24-28031-11 strut in accordance with Section 28 of the FH-1100 Service Manual or an alternate method approved by the FAA. Apply RTV-102 sealant or equivalent to the threads of MS-21252 fork fitting and under AN316-5R retaining nut upon installation.
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Compliance Time
within the next 30 days after the effective date of this AD
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Affected Aircraft
Fairchild Hiller Models 1100 and FH-1100 Helicopters certificated in all categories.
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Federal Register Abstract
Failure of Transmission Mount Strut
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_71-24-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-24-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild Hiller Models 1100 and FH-1100 Helicopters Subject: Failure of Transmission Mount Strut Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/24/1971 Make: FH1100 Manufacturing Corporation Model: 1100 | FH-1100 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 71-24-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1334 AD NUMBER: 71-24-02 SUBJECT HEADING: Airworthiness Directives; Fairchild Hiller Models 1100 and FH-1100 Helicopters ACTION: SUMMARY: DATES: Effective November 24, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-24-02 FAIRCHILD HILLER ROTORCRAFT: Amdt. 39-1334. Applies to Model 1100 and FH-1100 Type Helicopters certificated in all categories. Compliance required as indicated. To preclude fatigue failure of the transmission mount strut, P/N 24-28031, due to internal corrosion, accomplish the following: Within the next 30 days after the effective date of this AD, unless already accomplished replace P/N 24-28031 left side, lateral, adjustable transmission strut with P/N 24-28031-11 strut in accordance with Section 28 of the FH-1100 Service Manual or an alternate method approved by the Chief, Engineering & Manufacturing Branch, FAA, Eastern Region. Upon installation of MS-21252 fork fitting apply RTV-102 sealant or equivalent to the threads of fitting and under AN316-5R retaining nut. This amendment is effective November 24, 1971. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_71-24-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-24-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild Hiller Models 1100 and FH-1100 Helicopters Subject: Failure of Transmission Mount Strut Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/24/1971 Make: FH1100 Manufacturing Corporation Model: 1100 | 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 71-24-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1334 AD NUMBER: 71-24-02 SUBJECT HEADING: Airworthiness Directives; Fairchild Hiller Models 1100 and FH-1100 Helicopters ACTION: SUMMARY: DATES: Effective November 24, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-24-02 FAIRCHILD HILLER ROTORCRAFT: Amdt. 39-1334. Applies to Model 1100 and FH-1100 Type Helicopters certificated in all categories. Compliance required as indicated. To preclude fatigue failure of the transmission mount strut, P/N 24-28031, due to internal corrosion, accomplish the following: Within the next 30 days after the effective date of this AD, unless already accomplished replace P/N 24-28031 left side, lateral, adjustable transmission strut with P/N 24-28031-11 strut in accordance with Section 28 of the FH-1100 Service Manual or an alternate method approved by the Chief, Engineering & Manufacturing Branch, FAA, Eastern Region. Upon installation of MS-21252 fork fitting apply RTV-102 sealant or equivalent to the threads of fitting and under AN316-5R retaining nut. This amendment is effective November 24, 1971. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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