fuse (hydraulic component). A hydraulic flow control valve that automatically closes when a given amount of fluid has passed, or when an excessive pressure drop occurs across the valve. Hydraulic fuses prevent the loss of all of the fluid in the event of a broken line.
fuse holder (electrical component). A device that holds a tubular fuse and makes connections to both its ends. A panel-mounted fuse holder makes it easy to replace a blown fuse.
fuselage (aircraft component). The body, or central structural component of an airplane. The passengers and flight crew are housed in the fuselage, and the wings and tail attach to it. In most single-engine airplanes, the engine and landing gear attach to the fuselage.
fuselage center line. A line parallel to the longitudinal axis of an airplane that divides the fuselage into symmetrical halves.
fuselage station (location in an aircraft structure). The location along the longitudinal axis of an aircraft that is a given number of inches ahead of or behind the datum, or reference plane.
fuse link (electrical component). A strip of low-melting-point metal used in an electrical fuse to protect a circuit. The amount of current that can flow through the fuse link before it melts and opens the circuit is determined by the size of the fuse link and the type of metal of which it is made.
fusible plug (aircraft wheel component). A safety plug used in an aircraft wheel that mounts a tubeless tire. The plug has a hole drilled through it, and this hole is filled with a low-melting-point alloy. If a wheel is overheated by the excessive use of the brakes during an aborted takeoff, the alloy in the plug will melt and deflate the tire. This prevents the air pressure in the tire building up high enough to cause an explosion.