AD 79-03-07
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12D | Airworthiness Directives; Hiller Models UH-12D and UH-12E Helicopters |
| aircraft | Hiller Aviation | Siam Hiller Holdings, Inc. | UH-12E | Airworthiness Directives; Hiller Models UH-12D and UH-12E Helicopters |
Unsafe Condition
Repeated execution of emergency procedures involving unnecessary external load deployment and full autorotation following false low rotor speed warning system activation.
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Required Actions
Replace Globe Industries' P/N 22A571 or P/N 22A580 main rotor tachometer generator with P/N 22A623 in accordance with Soloy Conversions, Limited Service Bulletin 03-560 or later FAA approved revisions. Silicone sealing procedures from the bulletin must be followed.
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Compliance Time
Within the next 200-hours time in-service or 1 month calendar time, whichever occurs first after the effective date of this AD.
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Affected Aircraft
Hiller Models UH-12D and UH-12E helicopters converted to turbine power under Soloy Conversions STC Nos. SH177WE and SH178WE respectively.
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Federal Register Abstract
Main Rotor Tachometer Generator
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_79-03-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-03-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hiller Models UH-12D and UH-12E Helicopters Subject: Main Rotor Tachometer Generator Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/21/1979 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12D | UH-12E Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 79-03-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3409 AD NUMBER: 79-03-07 SUBJECT HEADING: Airworthiness Directives; Hiller Models UH-12D and UH-12E Helicopters ACTION: SUMMARY: DATES: Effective February 21, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-03-07 HILLER AVIATION: Amendment 39-3409. Applies to Model UH-12D and UH-12E helicopters which have been converted to turbine power in accordance with Soloy Conversions, Limited, STC Nos. SH177WE and SH178WE respectively, certificated in all categories. Compliance required as indicated unless already accomplished. To reduce the hazard to aircraft and ground personnel as a result of repeated execution of emergency procedures involving unnecessary external load deployment and full autorotation following false low rotor speed warning system activation, accomplish the following: A. Within the next 200-hours time in-service, or 1 month calendar time, whichever occurs first after the effective date of this AD, replace Globe Industries' P/N 22A571 or P/N 22A580 main rotor tachometer generator with Globe Industries' P/N 22A623 main rotor tachometer generator in accordance with Soloy Conversions, Limited Service Bulletin 03-560 dated March 31, 1978, or later FAA approved revisions. Silicone sealing procedures required for installation of this new style generator are described in this bulletin. B. Equivalent methods of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest 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 Soloy Conversions, Limited, Post Office Box 60, Chehalis, Washington 98532. These documents may also be examined at FAA Northwest Region, 9010 E. Marginal Way South, Seattle, Washington 98108. This amendment becomes effective February 21, 1979. FOOTER:
Document Text
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AD Final Rules - DRS_79-03-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-03-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Hiller Models UH-12D and UH-12E Helicopters Subject: Main Rotor Tachometer Generator Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/21/1979 Make: Hiller Aviation | Siam Hiller Holdings, Inc. Model: UH-12D | UH-12E 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: 79-03-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3409 AD NUMBER: 79-03-07 SUBJECT HEADING: Airworthiness Directives; Hiller Models UH-12D and UH-12E Helicopters ACTION: SUMMARY: DATES: Effective February 21, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-03-07 HILLER AVIATION: Amendment 39-3409. Applies to Model UH-12D and UH-12E helicopters which have been converted to turbine power in accordance with Soloy Conversions, Limited, STC Nos. SH177WE and SH178WE respectively, certificated in all categories. Compliance required as indicated unless already accomplished. To reduce the hazard to aircraft and ground personnel as a result of repeated execution of emergency procedures involving unnecessary external load deployment and full autorotation following false low rotor speed warning system activation, accomplish the following: A. Within the next 200-hours time in-service, or 1 month calendar time, whichever occurs first after the effective date of this AD, replace Globe Industries' P/N 22A571 or P/N 22A580 main rotor tachometer generator with Globe Industries' P/N 22A623 main rotor tachometer generator in accordance with Soloy Conversions, Limited Service Bulletin 03-560 dated March 31, 1978, or later FAA approved revisions. Silicone sealing procedures required for installation of this new style generator are described in this bulletin. B. Equivalent methods of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest 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 Soloy Conversions, Limited, Post Office Box 60, Chehalis, Washington 98532. These documents may also be examined at FAA Northwest Region, 9010 E. Marginal Way South, Seattle, Washington 98108. This amendment becomes effective February 21, 1979. FOOTER:
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