摘要:
A computer aided design system accurately determines the location, shape, and dimensions of a transparency that provides a field of view meeting a clear view area specified by a two dimensional polar vision plot. The computer aided design system projects points on the two dimensional polar vision plot onto a three dimensional surface of the transparency taking into account the observer's head position and the refraction of light caused by the transparency.
摘要:
A non-volatile electron beam-addressed light-valve produces a flickerless, all-at-once visible light output which is then converted into a flickerless projected infrared scene suitable for testing an infrared imaging seeker.
摘要:
A method of prescoring foam board for making composite panels includes impressing a pattern of ridges projecting from a surface of a die into at least one face surface of the foam board. The pattern of ridges on the die forms a pattern of indentations having three series of parallel linear indentations, each series being angularly offset from each series other by 60.degree.. The ridges on the embossing die are pressed into the foam sufficiently deep that the the pattern of indentations impressed in the board surface after whatever springback occurs remain deep enough to enable volatiles generated in an interior zone of a panel to escape when drawn out by a vacuum pump when the foam board is heated under pressure between two face sheets of resin-preimpregnated fabric to form a composite panel.
摘要:
Resin flow into the cells of a honeycomb core in sandwich structures is eliminated by using an unsupported film adhesive, a barrier layer, and a scrim supported adhesive layer between the composite laminate and the core. Superior panels with lighter weights, improved mechanical properties, and more predictable structural performance result by keeping resin in the laminate rather than losing it to the core cells.
摘要:
A hole is formed in a high-strength steel part and a lubricant consisting essentially of one or more metal powders, preferably of nickel or molybdenum; a metal powder which is more reactive than the steel of the workpiece such as zinc; and an organic medium is applied. A forming mandrel having a generally cylindrical shape with a frustoconical portion on either end is centered over the hole. The mandrel is pushed through the hole at a rate such that the steel adjacent the hole is coldworked and its microstructure is transformed from an austenitic to a normal tempered martensitic structure.
摘要:
There is a core engine having a turbine section which is drivingly connected to a single propeller through a planetary transmission. The core engine provides a substantially continuous, axially aligned gaseous flow path from the inlet to the discharge nozzle, with the planetary drive being spaced radially from the flow path. In one configuration, the planetary transmission is spaced circumferentially around the flow path, while in another configuration, it is positioned inside of the annular flow path. The engine is ranged in both a tractor and a pusher configuration.
摘要:
A method of providing rapid conversion of an internal weapon carriage to an external weapon carriage on an aircraft and returning the external carriage to an internal carriage. The method of conversion providing an aircraft with the option of carrying either weapons with large fixed fins or converting to newer type weapons having either smaller fins or fins that can be folded thereon.
摘要:
The thrust control apparatus of the present invention is employed on an aircraft having a wing and a turbofan engine mounted on a strut extending downwardly and forwardly from the wing. The thrust control apparatus includes (a) a rearwardly opening turbine engine nozzle for directing primary turbine exhaust effluent rearwardly from the engine, (b) a fan and an annular fan duct surrounding the forward portion of the turbine engine, (c) a primary fan air duct being coupled to the annular fan air duct, extending upwardly and rearwardly from the annular fan duct, and terminating in a separate rearwardly opening fan air nozzle for directing the secondary fan effluent rearwardly from the engine, and (d) a first auxiliary duct being coupled to the primary fan air duct, extending upwardly therefrom, and terminating in an upwardly opening auxiliary fan air nozzle for directing fan air flowing through the first auxiliary duct upwardly in front of the aircraft wing. During cruise operation, a valve associated with the coupling between the primary duct and the first auxiliary duct is positioned to close the first auxiliary duct, allowing all of the fan effluent to be exhausted through the fan air nozzle. Upon approach to landing, the valve associated with the coupling of the primary duct and the first auxiliary duct is adjusted to a position where it bifurcates the fan effluent between the primary duct and the first auxiliary duct. At the same time the engine throttle is advanced, calling for the turbofan engine to generate near maximum r.p.m. A plurality of vanes in the first auxiliary nozzle directs the fan effluent flowing through the first auxiliary duct upwardly and rearwardly over the upper airfoil surface of the wing. Upon touchdown of the aircraft on the landing field, the valve associated with the coupling between the primary duct and the first auxiliary duct closes the primary duct diverting the entire flow of fan effluent through the first auxiliary duct. At the same time the plurality of vanes in the first auxiliary nozzle are shifted to direct the fan effluent upwardly and forwardly relative to the engine and the wing, thus reversing the flow direction of the fan effluent and providing a reverse thrust component to brake the aircraft.
摘要:
An AC to DC power supply for operational amplifiers and the like requiring positive and negative voltage sources, the supply incorporating means which will cause a short or current surge condition on either the plus or minus terminal of the power supply to reduce the voltage on both terminals. This will prevent the occurrence of a hard-over condition in an analog control system employing the operational amplifier, which hard-over condition would otherwise occur if only one of the positive and negative power supplies were to fail and not the other.
摘要:
A hydrofoil craft having foils carried on struts, the struts being supported for pivotal movement relative to the hull of the craft and held in position during foil-borne operation by a substantially rigid restraining device. The restraining device constitutes a mechanical fuse device which holds the strut in place during normal operation but ruptures or yields in response to impact forces on the strut to permit the strut to pivot in case it should strike an object in the water during high speed operation. The pivotal movement of the strut reduces the dangerously rapid deceleration that would otherwise occur and minimizes structural damage to the craft.