AD 75-07-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Rolls-Royce Corporation | 501-D22A | DETROIT DIESEL ALLISON Model 501-D22A Engines |
Unsafe Condition
Second stage turbine blades (part number 6852228) may fail due to high cycle fatigue, leading to engine failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove part number 6852228 second stage turbine blades and replace with part number 6890508 second stage turbine blades.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 300 hours' time in service after the effective date of this Airworthiness Directive
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Affected Aircraft
Detroit Diesel Allison Model 501-D22A engines with turbine assemblies having the specified serial numbers listed in the AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Second Stage Turbine Blades
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-07-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-07-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DETROIT DIESEL ALLISON Model 501-D22A Engines Subject: Second Stage Turbine Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/07/1975 Make: Rolls-Royce Corporation Model: 501-D22A Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-07-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2141 AD NUMBER: 75-07-06 SUBJECT HEADING: DETROIT DIESEL ALLISON Model 501-D22A Engines ACTION: SUMMARY: DATES: Effective April 7, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-07-06 DETROIT DIESEL ALLISON: Amendment 39-2141. Applies to Detroit Diesel Allison Model 501-D22A engines with turbine assemblies having the following serial numbers: 750137, 750138, 750139, 750140, 750142, 750143, 750145, 750146A, 750147A, 750149, 750150, 750151, 750154, 750158, 750160, 750166, 750176, 750177, 750179, 750181, 750182A, 750184, 750194, 750195, 750201A, 750204, 750205, 750208, 750212, 750213, 750214, 750229, 750230, 750231, 750235, 750241A, 750263A, 750266, 750272, 750301, 750305, 750309, 750312 Within the next 300 hours' time in service after the effective date of this Airworthiness Directive, unless already accomplished, remove the part number 6852228 second stage turbine blades and replace with part number 6890508 second stage turbine blades. Detroit Diesel Allison Commercial Overhaul Information Letter Number COIL-1019 pertains to this subject. This amendment is effective April 7, 1975. FOOTER:
Document Text
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AD Final Rules - DRS_75-07-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-07-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DETROIT DIESEL ALLISON Model 501-D22A Engines Subject: Second Stage Turbine Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/07/1975 Make: Rolls-Royce Corporation Model: 501-D22A 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: 75-07-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2141 AD NUMBER: 75-07-06 SUBJECT HEADING: DETROIT DIESEL ALLISON Model 501-D22A Engines ACTION: SUMMARY: DATES: Effective April 7, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-07-06 DETROIT DIESEL ALLISON: Amendment 39-2141. Applies to Detroit Diesel Allison Model 501-D22A engines with turbine assemblies having the following serial numbers: 750137, 750138, 750139, 750140, 750142, 750143, 750145, 750146A, 750147A, 750149, 750150, 750151, 750154, 750158, 750160, 750166, 750176, 750177, 750179, 750181, 750182A, 750184, 750194, 750195, 750201A, 750204, 750205, 750208, 750212, 750213, 750214, 750229, 750230, 750231, 750235, 750241A, 750263A, 750266, 750272, 750301, 750305, 750309, 750312 Within the next 300 hours' time in service after the effective date of this Airworthiness Directive, unless already accomplished, remove the part number 6852228 second stage turbine blades and replace with part number 6890508 second stage turbine blades. Detroit Diesel Allison Commercial Overhaul Information Letter Number COIL-1019 pertains to this subject. This amendment is effective April 7, 1975. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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