A ram air turbine (RAT) is a small wind turbine that is installed in an aircraft to be used as a source of power for additional safety during emergencies.
What Does a RAM Air Turbine Do?
The purpose of the RAM air turbine is to provide an aircraft with alternate or emergency hydraulic or electrical power. The RAT is able to generate this power from the airstream based on the speed of the aircraft. Depending on the generator, the large RATs commonly found on commercial aircraft are typically capable of producing 5 to 70 kW. Generation of power by smaller, low-airspeed models may reach as little as 400 watts.
The RAM Air Turbine System
RAM air turbines are connected to an electrical generator or a hydraulic pump and use the airstream to generate power by ram pressure from the aircraft’s speed. RAM air turbines use power based on the speed is generated when the aircraft is operating. For example, at a higher speed and more power is generated when operating at lower speeds.
Present-day aircraft will generally only use RAM air turbine’s (RATs) in an emergency where both the primary and secondary power sources are lost. If this occurs, the RAM air turbine is used to power the aircraft’s crucial systems such as flight controls, instruments, and aircraft hydraulic systems. Some types of RATs will only produce hydraulic power, which is then used to power generators.
What planes have a RAM Air Turbine?
RAM air turbines are commonly used in military aircrafts as this type of aircraft must be fully prepared for emergencies, including a complete loss of power. Ram Air Turbines are also used in civilian aircraft, in emergency situations, and sometimes to even power centrifugal pumps, which are used to pressurize the spray systems on crop-dusting aircraft. In the United States, using a RAM Air Turbine in crop-dusting aircraft is especially convenient, as it allows an FAA-certified engine and an aircraft’s power systems to operate without modification.
RAM air turbines are the core of an aircraft’s emergency power system and have even helped save 1,700 lives in 16 documented emergency situations. In the event of a power loss, the RAM air turbine’s RAT deploys from the wing or fuselage and derives power from the airstream to help control and land the aircraft. All in all, RAM air turbines are both useful and crucial in the aviation world, and in operating safe aircraft.