EASA Regulations for Honeywell International T5311

Engine Controls - Reduction Gearbox Assembly - Vibration Tests

The document titled "Engine Controls - Reduction Gearbox Assembly - Vibration Tests" is a Federal Aviation Administration (FAA) Airworthiness Directive (AD 2022-10-02) that applies to certain Honeywell International, Inc. T53 model turboshaft engines, including T5311A, T5311B, T5313B, T5317A, T5317B, T5317A-1, T5317BCV, and various former military T53 models. This AD mandates initial and repetitive special vibration tests of the engine's reduction gearbox assembly and requires replacement of the gearbox or engine if vibration limits are exceeded. The directive addresses unsafe conditions caused by tachometer drive spur gear failures that could lead to engine overspeed and loss of power turbine speed indication.