What type of pump does the CSU contain?

The correct choice regarding the type of pump contained in the Constant Speed Unit (CSU) is indeed a gear-type oil pump. In the context of aircraft engines, particularly those in the Pilatus PC-12 NG, the CSU plays a crucial role in regulating propeller speed by managing the flow of engine oil to the propeller blades.

A gear-type oil pump is designed to provide a steady flow of oil, which is essential for the operation of the CSU. It works by using interlocking gears to draw oil from the sump and force it under pressure to various components, including the CSU's actuators that adjust the blade pitch of the propeller. This consistent oil flow ensures that the propeller maintains the desired RPM, optimizing performance and efficiency during flight.

The other types of pumps mentioned would not serve this function as effectively for the CSU in this specific application. For instance, centrifugal pumps typically move fluid by transforming rotational kinetic energy into hydraulic energy, which is less suited for the precise oil management needs of a CSU. Diaphragm pumps and piston pumps, while useful in different applications, do not provide the same efficiency or reliability needed in a CSU environment. Therefore, the gear-type oil pump is the ideal choice for controlling oil flow in a