AD 78-05-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-58BT | Airworthiness Directives; Sikorsky Model S-58T Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58DT | Airworthiness Directives; Sikorsky Model S-58T Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58ET | Airworthiness Directives; Sikorsky Model S-58T Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58FT | Airworthiness Directives; Sikorsky Model S-58T Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58HT | Airworthiness Directives; Sikorsky Model S-58T Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58JT | Airworthiness Directives; Sikorsky Model S-58T Series Helicopters |
Unsafe Condition
Oil-to-fuel heater contamination could cause fuel starvation of the PT6T-3 and PT6T-6 engines.
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Required Actions
Relocate the impending fuel bypass sensor lines on both engine power sections following Sikorsky Service Bulletin No. 58B30-12C, dated January 12, 1976.
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Compliance Time
prior to May 25, 1978
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Affected Aircraft
Sikorsky Model S-58T series helicopters (S-58BT, S-58DT, S-58ET, S-58FT, S-58HT, S-58JT)
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Fuel Bypass Lines
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_78-05-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-05-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-58T Series Helicopters Subject: Fuel Bypass Lines Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/31/1978 Make: Sikorsky Aircraft Corporation Model: S-58BT | S-58DT | S-58ET | S-58FT | S-58HT | S-58JT Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 78-05-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3146 AD NUMBER: 78-05-01 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-58T Series Helicopters ACTION: SUMMARY: DATES: Effective March 31, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-05-01 SIKORSKY AIRCRAFT: Amendment 39-3146. Applies to all Model S-58T series helicopters. Compliance required prior to May 25, 1978. To preclude possible fuel starvation of the PT6T-3 and PT6T-6 engines resulting from oil-to-fuel heater contamination, relocate the impending fuel bypass sensor lines on both engine power sections in accordance with the instructions set forth in Part II, Paragraph A, of Sikorsky Service Bulletin No. 58B30-12C, dated January 12, 1976. This amendment becomes effective March 31, 1978. FOOTER:
Document Text
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AD Final Rules - DRS_78-05-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-05-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-58T Series Helicopters Subject: Fuel Bypass Lines Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/31/1978 Make: Sikorsky Aircraft Corporation Model: S-58BT | S-58DT | S-58ET | S-58FT | S-58HT | S-58JT 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: 78-05-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3146 AD NUMBER: 78-05-01 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-58T Series Helicopters ACTION: SUMMARY: DATES: Effective March 31, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-05-01 SIKORSKY AIRCRAFT: Amendment 39-3146. Applies to all Model S-58T series helicopters. Compliance required prior to May 25, 1978. To preclude possible fuel starvation of the PT6T-3 and PT6T-6 engines resulting from oil-to-fuel heater contamination, relocate the impending fuel bypass sensor lines on both engine power sections in accordance with the instructions set forth in Part II, Paragraph A, of Sikorsky Service Bulletin No. 58B30-12C, dated January 12, 1976. This amendment becomes effective March 31, 1978. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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