ram air turbine

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ram air turbine (RAT)

ram air turbine (RAT)
A ram air-driven turbine used in emergency situations to generate sufficient power to keep an aircraft flying long enough to land. Thus, the RAT performs the same function as an auxiliary power unit (APU). But, whereas an APU is essentially a small jet engine that burns regular jet fuel to generate this additional power, the RAT consists of a propeller that is spun by the high-speed air flowing past the aircraft. The spinning propeller powers a turbine that provides the emergency electricity needed to keep critical systems running, such as hydraulics, flight controls, and key avionics. In a normal flight, the entire assembly is folded up and stored in the aircraft fuselage or wing.
References in periodicals archive ?
The company said that it estimates total A350 XWB Ram Air Turbine (RAT) system revenues to be in excess of USD500m over the life of the multi-year programme.
The Connecticut-based company will provide Boeing with its ram air turbine system designed to provide electric and hydraulic power to the aircraft in the event that other power sources are disrupted.
This AD would require the replacement of the ejection jack on the ram air turbine.
The existing AD currently requires repetitive deployment tests of the ram air turbine (RAT) and checks of the adjustment of the locking rod, This proposed action would require modification of the RAT, which would terminate the repetitive tests and checks.
The European Aviation Safety Agency (EASA) has mandated that operators of a large variety of Airbus aircraft fitted with Hamilton Sundstrand ram air turbines (RATs) perform inspections and part replacement on the backup devices.