AD 69-26-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Rolls-Royce Corporation | 250-C18 | ALLISON Model 250-C18 Series Engines. |
| engine | Rolls-Royce Corporation | 250-C18A | ALLISON Model 250-C18 Series Engines. |
| engine | Rolls-Royce Corporation | 250-C18B | ALLISON Model 250-C18 Series Engines. |
| engine | Rolls-Royce Corporation | 250-C18C | ALLISON Model 250-C18 Series Engines. |
Unsafe Condition
Failure of the power and accessories gear box due to insufficient strength or fatigue.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Modify the engine and power and accessories gear box in accordance with specified Allison Commercial Engine Bulletins or an equivalent method approved by the FAA. Compliance must be completed by October 1, 1971.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
On or before October 1, 1971
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Affected Aircraft
Rolls-Royce Corporation Model 250-C18, 250-C18A, 250-C18B, 250-C18C engines.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Modify Power and Accessories Gear Box
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_69-26-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 69-26-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: ALLISON Model 250-C18 Series Engines. Subject: Modify Power and Accessories Gear Box Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/25/1969 Make: Rolls-Royce Corporation Model: 250-C18 | 250-C18A | 250-C18B | 250-C18C Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 69-26-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-895 AD NUMBER: 69-26-03 SUBJECT HEADING: ALLISON Model 250-C18 Series Engines. ACTION: SUMMARY: DATES: Effective December 25, 1969. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 69-26-03 ALLISON: Amdt. 39-895. Applies to Model 250-C18 Series Engines. Compliance: Unless already accomplished, accomplish the following: (1) At next overhaul but no later than 750 hours' time in service since last overhaul or since new if never overhauled, modify the engine in accordance with Allison Commercial Engine Bulletins numbered 250CEB-57, - 58, -59, -61, -62, -63, -65, -66, -67, -68, -69, -70, -72, -73, -74, -75, -76, -77, -78, -79, -80, -81, -85, -86 and -89, or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region, except as specified in (2) below. (2) At next overhaul but no later than 1125 hours' time in service since last overhaul or since new if never overhauled, modify the power and accessories gear box in accordance with applicable portions of Allison Commercial Engine Bulletins specified in (1) above, or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Central Region. (3) All engines must be modified in accordance with (1) and (2) above on or before October 1, 1971. This amendment becomes effective December 25, 1969. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_69-26-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 69-26-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: ALLISON Model 250-C18 Series Engines. Subject: Modify Power and Accessories Gear Box Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/25/1969 Make: Rolls-Royce Corporation Model: 250-C18 | 250-C18A | 250-C18B | 250-C18C 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: 69-26-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-895 AD NUMBER: 69-26-03 SUBJECT HEADING: ALLISON Model 250-C18 Series Engines. ACTION: SUMMARY: DATES: Effective December 25, 1969. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 69-26-03 ALLISON: Amdt. 39-895. Applies to Model 250-C18 Series Engines. Compliance: Unless already accomplished, accomplish the following: (1) At next overhaul but no later than 750 hours' time in service since last overhaul or since new if never overhauled, modify the engine in accordance with Allison Commercial Engine Bulletins numbered 250CEB-57, - 58, -59, -61, -62, -63, -65, -66, -67, -68, -69, -70, -72, -73, -74, -75, -76, -77, -78, -79, -80, -81, -85, -86 and -89, or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region, except as specified in (2) below. (2) At next overhaul but no later than 1125 hours' time in service since last overhaul or since new if never overhauled, modify the power and accessories gear box in accordance with applicable portions of Allison Commercial Engine Bulletins specified in (1) above, or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Central Region. (3) All engines must be modified in accordance with (1) and (2) above on or before October 1, 1971. This amendment becomes effective December 25, 1969. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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