The brake system on the GW-133 is a fail-safe mechanical disk brake and it is used to bring the rotor safely to a stop under a number of conditions. These include insufficient wind to continue running, too much wind and loss of mains connection – e.g. if there is a power cut.
Once fitted, the system continuously adjusts the brake release position to ensure that as the brake pads wear, the actuator resets the brake apply spring to the same pre-load after each braking event. Over time, the system will run out of scope for readjustment in the linkage and the brake pads themselves must be readjusted. However, the period between adjustment is greatly extended such that they will now not need any adjustment between routine services.