AD 62-17-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Pratt & Whitney Division | JT3C-12 | PRATT & WHITNEY Model JT3C-12 Engines |
Unsafe Condition
Fatigue cracking in the rear face of the P/N 359708 eighth stage compressor rotor disc.
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Required Actions
Inspect discs using an American Cystoscope Markers, Inc. Model B-175-AS-15 or FAA approved equivalent viewing instrument inserted through an inspection hole in the compressor case and eighth stage stator shroud. Reinspect every 90 hours' time in service after the last inspection. Remove and replace cracked discs. Remove all discs after 4,800 hours' time in service.
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Compliance Time
Compliance required as indicated.
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Affected Aircraft
All Pratt & Whitney Model JT3C-12 Turbojet Engines.
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Federal Register Abstract
Compressor Rotor Disc
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_62-17-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 62-17-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY Model JT3C-12 Engines Subject: Compressor Rotor Disc Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Pratt & Whitney Division Model: JT3C-12 Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 62-17-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 62-17-06 SUBJECT HEADING: PRATT & WHITNEY Model JT3C-12 Engines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 62-17-06 PRATT & WHITNEY: Amdt. 470 Part 507 Federal Register August 1, 1962. Applies to All JT3C-12 Turbojet Engines. Compliance required as indicated. To preclude fatigue cracking in the rear face of the P/N 359708 eighth stage compressor rotor disc, accomplish the following: (a) For discs previously inspected by the procedure described in paragraph (c), reinspect in accordance with paragraph (c) every 90 hours' time in service from the last inspection. (b) For discs not previously inspected by the procedure described in paragraph (c), inspect in accordance with paragraph (c) as follows: (1) Inspect discs with 1,000 or more hours' time in service within the next 90 hours' time in service and every 90 hours' time in service thereafter. (2) Inspect discs with less than 1,000 hours' time in service prior to the accumulation of 1,090 hours' time in service and every 90 hours' time in service thereafter. (c) Incorporate an inspection hole and plug in the compressor case and eighth stage stator shroud in accordance with Pratt & Whitney Aircraft letter dated June 21, 1962, and its attached sketch number L-53852. Using an American Cystoscope Markers, Inc. Model B-175-AS-15 or FAA approved equivalent viewing instrument inserted through this hole, inspect each eighth stage compressor rotor disc rear blade dovetail area and the entire circumferential area of the eighth stage disc spacer for possible cracks. If any crack indications are found, remove the engine prior to further flight and disassemble for confirmation of the indications. Replace cracked discs. (d) Remove all eighth stage compressor rotor discs P/N 359708 from further service after 4,800 hours' time in service. (e) Upon request of the operator, an FAA Maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator. (Pratt & Whitney Aircraft telegraphic message dated June 13, 1962, to Eastern Air Lines and Pratt & Whitney Aircraft letter dated June 21, 1962, and attached sketch L-53852 to Eastern Air Lines covers the same subject.) This directive effective August 1, 1962. Revised February 20, 1963. FOOTER:
Document Text
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AD Final Rules - DRS_62-17-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 62-17-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY Model JT3C-12 Engines Subject: Compressor Rotor Disc Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Pratt & Whitney Division Model: JT3C-12 Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 62-17-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 62-17-06 SUBJECT HEADING: PRATT & WHITNEY Model JT3C-12 Engines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 62-17-06 PRATT & WHITNEY: Amdt. 470 Part 507 Federal Register August 1, 1962. Applies to All JT3C-12 Turbojet Engines. Compliance required as indicated. To preclude fatigue cracking in the rear face of the P/N 359708 eighth stage compressor rotor disc, accomplish the following: (a) For discs previously inspected by the procedure described in paragraph (c), reinspect in accordance with paragraph (c) every 90 hours' time in service from the last inspection. (b) For discs not previously inspected by the procedure described in paragraph (c), inspect in accordance with paragraph (c) as follows: (1) Inspect discs with 1,000 or more hours' time in service within the next 90 hours' time in service and every 90 hours' time in service thereafter. (2) Inspect discs with less than 1,000 hours' time in service prior to the accumulation of 1,090 hours' time in service and every 90 hours' time in service thereafter. (c) Incorporate an inspection hole and plug in the compressor case and eighth stage stator shroud in accordance with Pratt & Whitney Aircraft letter dated June 21, 1962, and its attached sketch number L-53852. Using an American Cystoscope Markers, Inc. Model B-175-AS-15 or FAA approved equivalent viewing instrument inserted through this hole, inspect each eighth stage compressor rotor disc rear blade dovetail area and the entire circumferential area of the eighth stage disc spacer for possible cracks. If any crack indications are found, remove the engine prior to further flight and disassemble for confirmation of the indications. Replace cracked discs. (d) Remove all eighth stage compressor rotor discs P/N 359708 from further service after 4,800 hours' time in service. (e) Upon request of the operator, an FAA Maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, may adjust the repetitive inspection intervals specified in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for such operator. (Pratt & Whitney Aircraft telegraphic message dated June 13, 1962, to Eastern Air Lines and Pratt & Whitney Aircraft letter dated June 21, 1962, and attached sketch L-53852 to Eastern Air Lines covers the same subject.) This directive effective August 1, 1962. Revised February 20, 1963. FOOTER:
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Retrieved: Apr 8, 2026
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