Commonwealth legislation

AD/AL 250/11 Amdt 3 - Engine Improvement - Introduction of Blue Ribbon Modifications

In ForceCTH

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Commonwealth

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legislative instrument

Plain English Summary

3/10 complexity

This directive mandates “Blue Ribbon” physical modifications to Allison 250‑C18 turbine engines and their power/accessory gearboxes, requiring work at the next overhaul after 29 May 1970 and by fixed service-hour limits (engines by 750 TIS, gearboxes by 1,125 TIS). Operators, owners and maintenance organisations must follow the listed Allison Commercial Engine Bulletins (or FAA AD 69‑26‑3) to comply.

It matters because it creates mandatory overhaul work, parts, labour and downtime costs and limits discretion to scheduling and choosing an approved provider.

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Current sections

Direct links to the current provisions in AD/AL 250/11 Amdt 3 - Engine Improvement - Introduction of Blue Ribbon Modifications.

AD/AL 250/11 Amdt 3 - Engine Improvement - Introduction of Blue Ribbon Modifications

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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Allison Turbine Engines - 250 Series

AD/AL 250/11

Amdt 3

Engine Improvement - Introduction of “Blue Ribbon” Modifications

4/71

Applicability: All 250-C18 series.

Document: 1. Allison Commercial Engine Bulletins numbered 250 CEB 57, 58, 59 Rev. 1, 61,

62, 63, 65, 66, 67, 68, 69 (or 98) 70, 72, 73, 74, (or 105), 75 (or 104), 76, 77, 103,

79, 80, 81, 85 and 89; or

FAA AD 69-26-3.

Compliance: 1. At next overhaul after 29 May 1970 but not later than 750 hours’ time in service since last overhaul or since new if never overhauled, modify the engine in accordance with the applicable Allison CEBs listed in this AD.

At next overhaul after 29 May 1970 but not later than 1125 hours’ time in service since last overhaul or since new if never overhauled, modify the power and accessories gearbox in accordance with the applicable Allison CEBs listed in this AD.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/AL 250/11 Amdt 3 - Engine Improvement - Introduction of Blue Ribbon Modifications