Abstract: A trim tab is disclosed for use on an aerodynamic foil that has first and second surfaces which extend between a leading edge and a trailing edge. Structurally, the trim tab includes a tab member that is bounded by slits formed through each surface to extend from the trailing edge toward the leading edge. Also, the tab member is bounded by a slot formed between the slits on the second surface to establish a flange between the slot and the trailing edge. Further, the trim tab includes an actuator that is mounted on the foil between the slot and the leading edge. The actuator includes an actuator arm that is connected to the flange. As a result, extension and retraction of the actuator moves the tab member about a hinge-less tab that is created on the first surface.

Abstract: A method of indicating the presence of mechanical impact is used with a low-ductility material, such as a composite material, having a tensile elongation to failure of less than about 2 percent. The method includes preparing an indicator paint having an impact-sensitive component that produces a visible change when subjected to a mechanical impact, applying the indicator paint to the surface of the low-ductility material, placing the low-ductility material having the indicator paint thereon into circumstances where it may be subject to the mechanical impact, and thereafter inspecting the low-ductility material having the indicator paint thereon for the presence of the visible change. The method may be used to establish design criteria for the low-ductility material by establishing an impact-effect threshold value from the step of inspecting, and determining a design limit for the low-ductility material responsive to the impact-effect threshold value.

Abstract: An aircraft having an airframe made of a composite material is provided with an isolated ground in order to reduce the threat of electrical fires. The aircraft includes a voltage source and at least one electronic device mounted on the airframe. Further, a power wire isolated from the airframe interconnects the voltage source and the electronic device. Also, a ground wire isolated from the airframe interconnects the voltage source and the electronic device. As a result, the onboard electric circuits are isolated from the airframe. In order to reduce electromagnetic interference in the circuit, the aircraft may be provided with a powerside capacitor, to interconnect the power wire and the airframe, and a groundside capacitor, to interconnect the ground wire and the airframe.

Abstract: A trim tab is disclosed for use on an aerodynamic foil that has first and second surfaces which extend between a leading edge and a trailing edge. Structurally, the trim tab includes a tab member that is bounded by slits formed through each surface to extend from the trailing edge toward the leading edge. Also, the tab member is bounded by a slot formed between the slits on the second surface to establish a flange between the slot and the trailing edge. Further, the trim tab includes an actuator that is mounted on the foil between the slot and the leading edge. The actuator includes an actuator arm that is connected to the flange. As a result, extension and retraction of the actuator moves the tab member about a hinge-less tab that is created on the first surface.

Abstract: A windshield for a pressurized aircraft includes a single transparent unit that functions structurally to allow pressurization of the aircraft and to support the aircraft's fuselage in response to external loads. The windshield also functions operationally to provide the pilot with an unobstructed field of vision through an extended arc of more than two hundred degrees. For its manufacture, layers of the transparent unit are respectively bent along a straight center line to establish two curved portions that are symmetrical relative to a common plane. The layers are then laminated.

Abstract: An aircraft engine mount is disclosed which has removable struts attached between the front upper and lower portions of the engine and the airframe during servicing, and a front lower mount having a spherical bearing which permits the engine to pivot about a generally vertical axis at the front of the engine. A rear mounting ring attached to the engine is detachable from the airframe during servicing, accomplished by rotating the aft portion of the engine outward through an access door about an axis at the front of the engine. An angled load bearing pin attached to the rear portion of the engine supplements the rear mounting ring so as to transmit to the airframe the forward loads of the engine experienced during a crash.