A dual pressure control for a rotor brake actuator for vertical lift aircraft

In some aspects, a master cylinder assembly (11)) for vertical lift aircraft is configured to move pressurized fluid through a conduit (130a, 130b, 130c, 130d, 130e, 130f, 130g) in response to applied movement of an input lever (112). A low pressure relief valve (126) can be connected to a first conduit (130a) to limit pressure to a low level. An isolation valve (124) can be connected to the first conduit (130a) and configured to isolate the low pressure relief valve from the conduit (130a) when engaged. A high pressure relief valve (128) can be connected to a second fluid conduit (130b) to limit pressure to a high level. In some aspects, a rotor brake actuator (132) is fluidly connected to the first conduit (130a) and the second conduit (130b) and configured to engage a rotor brake in response to hydraulic fluid pressure.