Abstract: An aircraft flight line electrical distribution system has electrical conductors connected to a power source and a plurality of service cables are connected to the conductors at service points. In order to provide electrical services to individual aircraft each service cable is provided with a connector plug for connection to the aircraft and each connector plug has an electronic power interrupter for interrupting power to the aircraft when the power in the service cable is either or both exceeds or falls short of predetermined levels of power. The power interrupter compares a sensed signal in the power line to a preset control signal. The compared signals are supplied to a logic circuit which then maintains a power contactor in the power supply line in the closed position when the sensed signal is at a predetermined reference level with respect to the control signal.

Abstract: The present invention is directed to a collapsible road barrier which includes at least one horizontal reflective member which is attached to the upper portion of four supporting legs. The four supporting legs are positioned in pairs with the upper portion thereof hinged together and the lower portion thereof spaced from each other so as to provide support for the horizontal reflective member. The collapsible road barrier also includes a universally collapsible bunk positioned adjacent the lower ends of the supporting legs. The universally collapsible bunk is generally rectangular in shape with each of the four corners of the bunk being attached to one of the supporting legs to provide a surface upon which material such as ballast may be positioned. The collapsible road barrier is readily folded to provide for convenient storage.

Abstract: In an aircraft flight line servicing system there is provided an electrical power unit and an air compressor from which extend respectively a plurality of electrical and air distribution lines and a plurality of service islands are each connected to all of the electrical and air distribution lines. Each service island is provided with components for supplying both starting air and cooling air and electricity to aircraft. The distribution lines and service islands may be detachably mounted upon the surface of the flight line and have such a height and shape so as to enable aircraft tires to pass thereover.