AD 79-02-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Enstrom Helicopter Corporation, The | 280C | Airworthiness Directives; Enstrom Model F-28C and 280C Helicopters |
| aircraft | Enstrom Helicopter Corporation, The | F-28C | Airworthiness Directives; Enstrom Model F-28C and 280C Helicopters |
Unsafe Condition
Damage to the turbocharger and possible engine power loss due to insufficient torque on the bearing housing flange attachment screws and improper installation of the induction system components.
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Required Actions
Inspect the Rajay turbocharger and determine if its serial number is 70484 or greater. For turbochargers with serial numbers less than 70484, remove the turbocharger, torque the bearing housing flange attachment screws to 90 + 10 inch-pounds, stake the screws, reinstall the compressor housing with a new gasket, and reinstall the turbocharger. Additionally, remove the induction system air inlet filter, replace the AN815-6D union with an AN832-6D union, and reattach the fuel nozzle air vent line.
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Compliance Time
Within 50 hours time in service after the effective date of this AD
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Affected Aircraft
Enstrom Model F-28C and 280C helicopters certificated in all categories
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Federal Register Abstract
Turbochargers
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_79-02-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-02-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Enstrom Model F-28C and 280C Helicopters Subject: Turbochargers Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/17/1979 Make: Enstrom Helicopter Corporation, The Model: 280C | F-28C Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 79-02-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3390 AD NUMBER: 79-02-01 SUBJECT HEADING: Airworthiness Directives; Enstrom Model F-28C and 280C Helicopters ACTION: SUMMARY: DATES: Effective January 17, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-02-01 ENSTROM HELICOPTERS: Amendment 39-3390. Applies to Enstrom Model F-28C and 280C helicopters certificated in all categories. Compliance required as indicated, unless previously accomplished. In order to prevent damage to the turbocharger and possible engine power loss accomplish the following: Within 50 hours time in service after the effective date of this AD, accomplish the following: A. Inspect the Rajay turbocharger. If the turbocharger serial number is 70484 or greater, proceed with step B. If the turbocharger serial number is less than 70484 accomplish the following: 1. Remove the turbocharger from the helicopter in accordance with the Enstrom Maintenance Manual. 2. Using a 5/32 Allen wrench, remove the six counter-sunk cap screws that secure the compressor housing to the bearing housing assembly. If necessary, gently tap the compressor housing with a plastic hammer to loosen it from the bearing housing assembly. 3. Torque the three bearing housing flange attachment screws on the turbocharger to 90 + 10 inch-pounds. "Stake" the screws in place in accordance with the sketch and notes which follow this AD. 4. Reinstall the compressor housing by placing the turbocharger on the compressor housing using a new gasket, Rajay P/N TC6-44. Secure with six cap screws and tighten evenly and alternately to 90 + 10 inch-pounds. 5. Reinstall the turbocharger in the helicopter in accordance with the Enstrom Maintenance Manual. B. Remove the induction system air inlet filter in accordance with the Enstrom Maintenance Manual. C. Remove the AN815-6D union which attaches the fuel nozzle air vent installation to the induction system air inlet filter container. Save the AN924-6D nut which was holding the union in place, for reinstallation, in accordance with step D. D. Install an AN832-6D union, in place of the AN815-6D union, so that the AN924-6D nut is outside of the filter container. E. Attach the fuel nozzle air vent line to the AN832-6D union. F. Replace the air filter in accordance with the Enstrom Maintenance Manual. Equivalent methods of compliance may be approved by the Chief, Engineering and Manufacturing Branch, FAA Great Lakes Region. This amendment becomes effective January 17, 1979. FOOTER:
Document Text
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AD Final Rules - DRS_79-02-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-02-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Enstrom Model F-28C and 280C Helicopters Subject: Turbochargers Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/17/1979 Make: Enstrom Helicopter Corporation, The Model: 280C | F-28C 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: 79-02-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3390 AD NUMBER: 79-02-01 SUBJECT HEADING: Airworthiness Directives; Enstrom Model F-28C and 280C Helicopters ACTION: SUMMARY: DATES: Effective January 17, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-02-01 ENSTROM HELICOPTERS: Amendment 39-3390. Applies to Enstrom Model F-28C and 280C helicopters certificated in all categories. Compliance required as indicated, unless previously accomplished. In order to prevent damage to the turbocharger and possible engine power loss accomplish the following: Within 50 hours time in service after the effective date of this AD, accomplish the following: A. Inspect the Rajay turbocharger. If the turbocharger serial number is 70484 or greater, proceed with step B. If the turbocharger serial number is less than 70484 accomplish the following: 1. Remove the turbocharger from the helicopter in accordance with the Enstrom Maintenance Manual. 2. Using a 5/32 Allen wrench, remove the six counter-sunk cap screws that secure the compressor housing to the bearing housing assembly. If necessary, gently tap the compressor housing with a plastic hammer to loosen it from the bearing housing assembly. 3. Torque the three bearing housing flange attachment screws on the turbocharger to 90 + 10 inch-pounds. "Stake" the screws in place in accordance with the sketch and notes which follow this AD. 4. Reinstall the compressor housing by placing the turbocharger on the compressor housing using a new gasket, Rajay P/N TC6-44. Secure with six cap screws and tighten evenly and alternately to 90 + 10 inch-pounds. 5. Reinstall the turbocharger in the helicopter in accordance with the Enstrom Maintenance Manual. B. Remove the induction system air inlet filter in accordance with the Enstrom Maintenance Manual. C. Remove the AN815-6D union which attaches the fuel nozzle air vent installation to the induction system air inlet filter container. Save the AN924-6D nut which was holding the union in place, for reinstallation, in accordance with step D. D. Install an AN832-6D union, in place of the AN815-6D union, so that the AN924-6D nut is outside of the filter container. E. Attach the fuel nozzle air vent line to the AN832-6D union. F. Replace the air filter in accordance with the Enstrom Maintenance Manual. Equivalent methods of compliance may be approved by the Chief, Engineering and Manufacturing Branch, FAA Great Lakes Region. This amendment becomes effective January 17, 1979. FOOTER:
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Retrieved: Apr 8, 2026
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