Abstract: A tiltwing aircraft, capable of in-flight conversion between a hover and forward cruise mode, employs a counter-rotating proprotor arrangement which permits a significantly increased cruise efficiency without sacrificing either the size of the conversion envelope or the wing efficiency. A benefit in hover is also provided because of the lower effective disk loading for the counter-rotating proprotor, as opposed to a single rotation proprotor of the same diameter. At least one proprotor is provided on each wing section, preferably mounted on the wingtip, with each proprotor having two counter-rotating blade rows. Each blade row has a plurality of blades which are relatively stiff-in-plane and are mounted such that cyclic pitch adjustments may be made for hover control during flight.

Abstract: A hybrid resistance card (R-Card) is manufactured using a two-step process wherein an electrically conductive ink layer and an electrically resistive ink layer are printed onto a surface, which may be either a substrate or the part on which the R-Card is to be used. The conductive ink layer is selectively applied in a pattern of shapes to electrically short out portions of the resistive ink layer, thereby permitting the R-Card to have a predetermined resistive taper across its width according to a desired resistivity curve. The resistive ink layer comprises grid-like lines bordering and separating the conductive shapes. The resistive taper is substantially continuous along the length of the R-Card, at least linearly, though if the card is designed to cover an entire part, it is substantially continuous along a plurality of directions on the card, with the tapers being designed to round into one another.

Abstract: A retractable gun for mounting within the fuselage of an aircraft, typically a helicopter, is disposed in a firing position and aimed by rotation of a turret which is coupled to and parallel to the longitudinal axis of the aircraft. The gun is aimed by simultaneous and independent rotation of the gun about an elevation pivot axis through which the gun is coupled to the turret. The turret axis and turret is disposed within an enclosure or within the fuselage of the airplane to allow withdrawal of the gun and turret from their exposed position. However, even in the enclosed position the gun can be fired. The elevation pivot axis is approximately perpendicular to the turret axis and permits two independent degrees of rotational freedom with which the gun may be aimed. Thus, the gun may be aimed at any point within at least a hemispherical range beneath the fuselage of an aircraft.