Abstract: The invention relates to improvements with regards to the control of VTOL aircraft that use two propellers or fans as the primary lifting devices in hover. More particularly, the invention is a means for effecting control of the aircraft using just the two propellers alone, and comprises the in-flight tilting of them—which are of the conventional, non-articulated type (though they may have collective blade-pitch)—directly and equally towards or away from one another (and therefore about parallel axes) as necessary for the generation of propeller torque-induced and gyroscopic control moments on the aircraft about an axis perpendicular to the propeller tilt and mean-spin-axes. For a side-by-side propeller arrangement, therefore, their (lateral) tilting towards or away from one another produces aircraft pitch control moments for full control of the aircraft in that direction.

Abstract: A method of on site application of an erosion resistant coating. When deposited on the surface of a metallic substrate, the coating comprises hard ferroboride phases bound with a ductile metallic phase. The ductile metallic phase is selected from metals which have a low affinity for oxygen. The preparation and composition of a cored wire adapted for use in application of the erosion resistant coatings are also disclosed.

Abstract: A robot especially adapted for use in hazardous environments, and particularly adapted for explosives disposal, includes a wheeled platform carrying a winder mechanism which ensures that the remote control cable will not be fouled by the robot or its attachments. Coaxial with the winder mechanism is a turret mechanism that can rotate indefinitely and which carries thereon a manipulator arm section which, includes a first arm pivotable through about 110.degree. and which carries thereon a second arm which is pivotable through about 120.degree. and carries a bulkhead to which any of a plurality of end effectors can be connected by way of a quick connect and disconnect mechanism. The end effectors include a set of links having different lengths, one or two extension links, a wrist and gripper mechanism, an aiming and disruptor mechanism, and a relocatable surveillance camera.

Abstract: Tubes for use in nuclear reactors fabricated from a quaternary alloy comprising 2.5-4.0 wt% Sn, 0.5-1.5 wt% Mo, 0.5-1.5 wt% Nb, balance essentially Zr. The tubes are fabricated by a process of hot extrusion, heat treatment, cold working to size and age hardening, so as to produce a microstructure comprising elongated .alpha. grains with an acicular transformed .beta. grain boundary phase.