Abstract: Control apparatus having two-fault tolerance for two position, motor operated actuators includes electronic circuitry for disconnection of the power return to the actuator motor armature thereby insuring that the motor will not be activated upon an inadvertent connection of power to either motor power input, and for indication of disconnection thereto. Testing determines the operatonal status of a motor relay and also determines inadvertent applications of power to the one of the pair of motor power inputs that is not connected to the power source through the position switch and one of the pair of limit switches. A relay and motor indication are operable to indicate either motor operation or inadvertent power interruptions in the one of the pair of motor power inputs most recently connected to the power source through the position switch and one of the pair of limit switches.

Abstract: A multi-engine helicopter fuel supply balance system effects automatic trfer of fuel from a larger tank to a smaller tank in response to low fuel level in the smaller tank when in automatic mode, and effects a transfer of a predetermined quantity of fuel between selected tanks by timed operation of a constant delivery pump when in manual mode.

Abstract: A crashworthy aircraft fuel storage system normally operative so that the fuel tank, fuel shut-off valve assembly and the fuel inlet connection to the fuel tank are normally assembled to be free floating with respect to the aircraft structure, and further operative so that crash load conditions will cause the fuel tank to move with respect to the aircraft structure to thereby cause fuel inlet fitting to move therewith and into contact with the aircraft structure so as to impose a momentum force on the fuel shut-off valve assembly to cause fracture thereof and separation of the fuel tank from the fuel inlet fitting, with both parts so separated, sealed to prevent fuel flow therethrough.