- 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 vacuum tube, or electron tube, whose cathode is made of a material that emits (gives off) electrons at normal room temperature. Cold-cathode vacuum tubes do not have filaments, or heaters.
Industry:Aviation
A value used in trigonometry that is the inverse, or opposite, of the tangent. This is the same as one divided by the tangent. The tangent of an angle is the ratio of the length of the side opposite the angle, to the length of the side adjacent, or next to, the angle.
If the sides of a triangle that form a right angle are two inches and three inches, the tangent of one of the angles is 2/3, or 0.667. The arc tangent is the angle whose tangent is 0.667, and this is 33.7°. This is normally written as Tan-1 0.667.
Industry:Aviation
A value used to measure the heating effect of sine-wave alternating current. The rms value is found by dividing one alternation of the AC into an infinite number of instantaneous values. Each instantaneous value is squared (multiplied by itself), and all of the squares are averaged to find the average, or mean, square. The square root is taken of this mean square.
The rms value of sine wave alternating current is 0.707 time the peak value of one alternation. One ampere rms has a peak value of 1.414 ( ) amps and produces the same amount of heat as one amp of direct current. The rms value is also called the effective value. Roots-type air compressor. A positive-displacement air pump that uses two intermeshing figure-8-shaped rotors to move the air.
Industry:Aviation
A valve attached to a sealed can of liquid refrigerant that controls the flow of refrigerant into an aircraft vapor-cycle cooling system.
When the valve is securely attached, a seal on the can is pierced, allowing the refrigerant to flow.
Industry:Aviation
A valve in a fluid power system that reduces the pressure of a liquid or gas from a high value to a fixed lower value.
Industry:Aviation
A valve in an aircraft cabin pressurization system that prevents the pressure inside the cabin ever becoming lower than the pressure of the air outside of the cabin.
Industry:Aviation
A valve in an oxygen system through which oxygen from the storage bottles is put into the system. Filler valves normally incorporate a restriction that prevents the system from being filled too quickly. If they were filled too quickly, enough heat could be built up to cause an explosion.
Industry:Aviation
A valve in the compressor case of an axial-flow gas turbine engine that allows some of the air to bleed off.
By bleeding off some of the pressure, the airflow through the engine is improved, and there is less danger of compressor stall or surge.
Industry:Aviation
A valve in the flap system of an airplane that prevents the flaps being lowered at an airspeed which could cause structural damage. If the pilot tries to extend the flaps when the airspeed is too high, the opposition caused by the airflow will open the overload valve and return the fluid to the reservoir.
Industry:Aviation
A valve in the induction system of a reciprocating engine that directs air either from the air filter or from a point inside the engine nacelle into the carburetor or the fuel injection system.
The alternate air valve on an engine equipped with a carburetor is called a carburetor heat valve.
Industry:Aviation
