Vibration testing of an APT-P trailer car non-parking tread brake actuator with turnbuckle (TM-PBS-22)

A modification to the APT-P trailer car non-parking tread brake actuator introduced a turnbuckle into the piston rod. This modification was necessitated by the malfunction of the original brake-arm slack adjusters. Vibration tests of the APT-P power car-parking brake actuators are reported in References 1 and 2. Failure during those...