- Industry: Aviation
- Number of terms: 16387
- Number of blossaries: 0
- Company Profile:
Aviation Supplies & Academics, Inc. (ASA) develops and markets aviation supplies, software, and books for pilots, flight instructors, flight engineers, airline professionals, air traffic controllers, flight attendants, aviation technicians and enthusiasts. Established in 1947, ASA also provides ...
A type of oscillator in which there are two active devices (transistors or electron tubes) which alternate in conducting. Multivibrators may be free running, bistable, or monostable. A free-running multivibrator automatically switches back and forth between the devices and continues to do this as long as power is supplied.
In a monostable multivibrator, one device is normally conducting, but a pulse on its base or grid will switch it off and the other one on. As soon as the pulse is removed, the conduction is switched back to the first.
In a bistable multivibrator, either device conducts equally well. A pulse on the base or grid of the first device turns it off and causes the second one to conduct until it receives a pulse on its base or grid. It then turns off, and conduction reverts back to the first.
Industry:Aviation
A type of oscillator using two transistors. Only one transistor conducts at a time, and it will continue to conduct until an external pulse causes it to stop conducting. When the first transistor stops conducting, the second transistor automatically begins to conduct.
A bistable multivibrator is called a flip-flop, and it is often used in digital electronics.
Industry:Aviation
A type of oxygen mask that covers only the mouth and nose of the wearer. An oronasal mask is distinguished from the full face mask, which covers the entire face as well as the eyes of the person wearing it.
Industry:Aviation
A type of oxygen system used by aircraft that fly at very high altitude. This system functions as a diluter-demand system below about 40,000 feet. Above this altitude, the regulator furnishes the mask with 100% oxygen under pressure to force the oxygen into the lungs, rather than depending on the low pressure produced when the wearer of the mask inhales to pull in the oxygen.
Industry:Aviation
A type of paint having components that cause it to emit light, or glow in the dark. Radium was, at one time, the main component in luminous paint. But because of its harmful characteristics, it has been replaced by other materials. Luminous paint is used on instrument dials and pointers to make them visible in the dark.
Industry:Aviation
A type of panel-mounted instrument used to show the frequency of the alternating current being supplied to certain electrical equipment. Metal reeds of different lengths are vibrated by an electromagnet powered by the AC whose frequency is being measured. The reed whose resonant frequency is the same as the frequency of the AC will vibrate with a much greater amplitude than the other reeds.
The ends of all of the reeds are visible on the face of the instrument, and each reed is identified by the frequency at which it is resonant. The number beside the reed seen as a wide blur is the frequency of the AC.
Industry:Aviation
A type of patch made in an aircraft plywood structure in which the edges of the patch are tapered for approximately five times the thickness of the plywood. A splayed patch is not recommended for use on plywood less than 1/10-inch thick.
Industry:Aviation
A type of patch made to a thin plywood structure. The damaged area is cleaned out and the edges of the hole tapered, with the length of the taper about 12 times the thickness of the plywood. Temporary backing blocks support the area while the patch is glued in place. A scarfed patch is the most difficult to make, but it is the preferred patch for aircraft plywood skins.
Industry:Aviation
A type of patch welded over a cluster in a welded truss-type aircraft fuselage. The patch covers and reinforces damaged areas of the tubes and has fingers that extend out along each of the tubes in the cluster.
Industry:Aviation
A type of plastic material that becomes soft when it is heated, and hardens when it is cooled. Thermoplastic materials can be softened and hardened many times without the strength or quality of the material being affected. Transparent acrylic plastic resin is an example of a thermoplastic material.
Industry:Aviation
