AD 86-19-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Rolls-Royce Corporation | 250-C30 | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30G | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30G/2 | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30M | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30P | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30R (T703-AD-700) | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30R/1 (T703-AD-700B) | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30R/3 | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30S | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
| engine | Rolls-Royce Corporation | 250-C30U | ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORP. Model 250-C30 Series Engines |
Unsafe Condition
Conditions that can lead to a possible gas producer turbine rotor uncontained failure and to prevent critical secondary damage in the event of a gas producer turbine rotor uncontained failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install engine compartment protective shields and energy absorbing rings, inspect protective shields at intervals not to exceed 25 hours time-in-service, update engines to the 'Allison Assured Engine' configuration, install internal energy absorbing rings, replace second stage turbine wheels, remove external energy absorbing rings, and remove engine compartment shields after compliance with specified modifications.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
At the next turbine repair/overhaul shop visit after the effective date of this AD, but not later than November 30, 1986 for Sikorsky Model S-76A installations and November 30, 1987 for other aircraft.
AI-generated summary from the source AD text. Verify against the official source before acting.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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