Abstract: An improved ram air turbine (RAT) prevents release of its turbine blades due an over-speed condition by detecting an over-speed condition with a trigger mechanism and rotating the blades to a fixed coarse pitch position with a release mechanism.

Abstract: Turbine nozzle phasing device for controlling a flow of gasses to a plurality of nozzles in response to a control signal. The turbine nozzle phasing device includes a housing having a lower portion which includes a first plenum for receiving the flow of hot gasses and an upper portion which includes a second plenum integral with the first plenum, a detachable partition for separating the first plenum from the second plenum and a first nozzle which communicates with the first plenum. Hot gasses flowing into the first plenum flows through the first nozzle. A set of second nozzles is provided which communicates with the second plenum. Partition detaching apparatus is also included for detaching the detachable partition in response to the control signal to permit a portion of the hot gasses flowing into the first plenum to flow into the second plenum and through the set of second nozzles.