Various embodiments of the present application provide one or more of: (1) auxiliary wheel that (a) enables accurate speed detection of a turbine disc and/or (b) presents a machining surface for balance correction; and/or (2) techniques for mounting an auxiliary wheel to a rotor, such as a turbine disc.

The invention relates to an overspeed protection device of an aircraft engine

A system includes a turbine exhaust section. The turbine exhaust section includes an exhaust flow path. The turbine exhaust section also includes an inner exhaust wall radially disposed along the exhaust flow path and an outer exhaust wall disposed along the exhaust flow path and radially outward from the inner exhaust wall. The turbine exhaust section includes an inner flow control vane configured to selectively extend radially outward from the inner exhaust wall. An inner radial extent of the inner flow control vane is less than a radial distance between the inner exhaust wall and the outer exhaust wall. The inner flow control vane is disposed downstream of a last stage blade of a turbine and upstream of an exhaust diffuser strut of the turbine exhaust section.

A control device includes a fuel equivalent value calculation unit for determining the flow rate of fuel supplied to a gas turbine in accordance with a target value deviation between an actual rotation speed and a target rotation speed, an upper limit deviation calculation unit for obtaining an upper limit deviation which is a deviation between a set upper limit output and an actual output, a lower limit deviation calculation unit for obtaining a lower limit deviation which is a deviation between a set lower limit output and the actual output, and a parameter-changing unit for changing any one parameter among the target rotation speed, the actual rotation speed, and the target value deviation so that the target value deviation decreases when the actual rotation speed decreases and the upper limit deviation is small, and so that the target value deviation increases when the actual rotation speed increases and the lower limit deviation is small.