AD 70-26-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Pratt & Whitney Division | JT8D-1 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-11 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-15 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-15A | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-17 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-17A | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-17AR | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-17R | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-1A | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-1B | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-209 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-217 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-217A | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-217C | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-219 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-5 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-7 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-7A | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-7B | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-9 | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
| engine | Pratt & Whitney Division | JT8D-9A | PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines |
Unsafe Condition
Failure of the first stage compressor rotor blades due to improperly machined blade roots with tool marks within the radius of the Z plane platform on both sides of the blade root area.
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Required Actions
Visually inspect all P/N 487801, 511901 change letter L or earlier, 594601 and 616601 change letter B or earlier first stage compressor rotor blades for tool marks within the specified area. Replace blades if tool marks are observed. Compliance time may be adjusted upon submission of substantiating data through an FAA Maintenance Inspector.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 900 hours in service after the effective date of this AD
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Affected Aircraft
Pratt & Whitney Aircraft Model JT8D series turbofan engines including models JT8D-1, JT8D-11, JT8D-15, JT8D-15A, JT8D-17, JT8D-17A, JT8D-17AR, JT8D-17R, JT8D-1A, and others listed in the source.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
First Stage Compressor Rotor Blades
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_70-26-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-26-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines Subject: First Stage Compressor Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/29/1970 Make: Pratt & Whitney Division Model: JT8D-1 | JT8D-11 | JT8D-15 | JT8D-15A | JT8D-17 | JT8D-17A | JT8D-17AR | JT8D-17R | JT8D-1A | JT8D-1...Show more 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: 70-26-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1131 AD NUMBER: 70-26-05 SUBJECT HEADING: PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines ACTION: SUMMARY: DATES: Effective December 29, 1970. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-26-05 PRATT & WHITNEY AIRCRAFT: Amdt. 39-1131. Applies to all model JT8D series turbofan engines. Compliance required as indicated. To prevent failure of the first stage compressor rotor blades as the result of improperly machined blade roots, accomplish the following: (a) Within the next 900 hours in service after the effective date of this AD, unless already accomplished, visually inspect all P/N 487801, 511901 change letter L or earlier, 594601 and 616601 change letter B or earlier first stage compressor rotor blades, for tool marks within the radius of the Z plane platform on both sides of the blade root area. If tool marks are observed, replace the blade. (b) Upon submission of substantiating data through an FAA Maintenance Inspector by an owner or operator to the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, compliance time may be adjusted. (Pratt & Whitney letter PSE:HHB:0-4-6-1-33 dated April 6, 1970, pertains to this subject.) This amendment is effective December 29, 1970. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_70-26-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-26-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines Subject: First Stage Compressor Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/29/1970 Make: Pratt & Whitney Division Model: JT8D-1 | JT8D-11 | JT8D-15 | JT8D-15A | JT8D-17 | JT8D-17A | JT8D-17AR | JT8D-17R | JT8D-1A | JT8D-1...Show more 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: 70-26-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1131 AD NUMBER: 70-26-05 SUBJECT HEADING: PRATT & WHITNEY AIRCRAFT Model JT8D Series Engines ACTION: SUMMARY: DATES: Effective December 29, 1970. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-26-05 PRATT & WHITNEY AIRCRAFT: Amdt. 39-1131. Applies to all model JT8D series turbofan engines. Compliance required as indicated. To prevent failure of the first stage compressor rotor blades as the result of improperly machined blade roots, accomplish the following: (a) Within the next 900 hours in service after the effective date of this AD, unless already accomplished, visually inspect all P/N 487801, 511901 change letter L or earlier, 594601 and 616601 change letter B or earlier first stage compressor rotor blades, for tool marks within the radius of the Z plane platform on both sides of the blade root area. If tool marks are observed, replace the blade. (b) Upon submission of substantiating data through an FAA Maintenance Inspector by an owner or operator to the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, compliance time may be adjusted. (Pratt & Whitney letter PSE:HHB:0-4-6-1-33 dated April 6, 1970, pertains to this subject.) This amendment is effective December 29, 1970. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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Related Airworthiness Directives
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