Dragging brakes can cause serious overheating, and may be caused by a malfunction in the brake master cylinder or by warped disks.
drag hinge (helicopter rotor component). A hinge in the rotor system of a helicopter that allows the individual blades to move back and forth in their plane of rotation. This movement helps minimize vibration. The drag hinge is also called the lead-lag hinge.
drag wire (aircraft structure). A structural wire inside a Pratt truss airplane wing between the spars. Drag wires run from the front spar inboard, to the rear spar at the next bay outboard. Drag wires oppose forces that try to drag a wing backward. Each drag wire is crossed by an antidrag wire.
drain (electronics). The electrode in a field effect transistor (FET) through which load current flows. Load current flowing from the source to the drain is controlled by the amount of voltage applied to the gate. The drain of an FET corresponds to the collector in a bipolar transistor.
drain can (jet aircraft component). A container in a jet aircraft engine compartment used to collect the fuel which drains from the main fuel manifold when the engine is shut down.
drain hole (aircraft structure). A small hole in the lowest part of an aircraft structure, used to ventilate the inside of the structure and to drain any water which collects in this area.
drain plug. A removable plug in the lowest point of a liquid container. The plug is removed to drain the liquid.
drape (textile characteristic). The ability of a woven fabric to conform to a contoured shape.
draw filing. A method of cutting metal or plastic with a hand file by moving the file crosswise over the work. Draw filing produces a very smooth finish.
drawing number (aircraft drawing). The number assigned to an aircraft drawing. The drawing number is located in the title block in the lower right-hand corner of the drawing. Drawing numbers often become the part number of the part made from the drawing.
drawknife. A woodworking tool consisting of a sharp blade with two handles, one at either end of the blade, mounted at right angles to the blade. A drawknife is pulled across the work to shave off part of its surface or to make its edges round.
draw set (riveting tool). A metalworking hand tool used to draw sheets of metal closely together before they are riveted.
A draw set is a steel bar with a hole drilled in one end to fit loosely over the shank of a rivet. The rivet is put through the holes in the sheets of metal, and the draw set is placed over the rivet shank. Then the rivet head is tapped lightly with the rivet set. This procedure draws the sheets of metal closely together before the rivet is actually driven.
drift (navigation). The term used in navigation for the sideways movement of an aircraft caused by the wind. Drift must be corrected for by heading the aircraft slightly into the direction from which the wind is blowing.
drift angle (aircraft flight). The angular difference between the direction an aircraft is headed in flight and the direction it actually moves over the ground.
|
