- 行业: 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 propeller whose blades can be moved to an extremely high pitch angle of approximately 90° so they face directly into the airstream and produce no aerodynamic forces. If an engine fails in flight, the aerodynamic forces acting on the propeller will cause it to continue to turn, or windmill.
A windmilling propeller produces enough drag on a multiengine aircraft to cause extreme control difficulties, and it can easily lead to a crash. To decrease the drag, the propeller blades can be feathered. Because a feathered propeller does not turn the engine, a damaged engine is prevented from destroying itself.
Industry:Aviation
A propeller whose pitch can be changed in flight. A two-position propeller is one that can be set to a low pitch angle for takeoff, and then in flight, the pitch angle can be increased for a more economical cruise.
A constant-speed propeller is a variable-pitch propeller whose pitch is controlled by a governor to keep the RPM of the engine constant as the air loads on the propeller change.
Industry:Aviation
A proper fraction whose denominator is a number which is a power of ten. The value of the denominator is not written, but it is indicated by the position of the decimal point.
One digit to the right of the decimal point means that the denominator is 10 (0.1 = 1/10); two digits to the right of the decimal shows the denominator is 100 (0.01 = 1/100), and three digits indicates 1,000 (0.001 = 1/1,000).
Industry:Aviation
A property or characteristic of certain unstable chemical elements in which they lose some of their neutrons. As they lose neutrons, they change into stable isotopes of the element or into atoms of other elements having different chemical properties.
Industry:Aviation
A property possessed by certain materials that causes them to attract or repel other materials having this same property. Magnetism also causes electrical current to flow in a conductor when it is moved across the lines of magnetic flux extending out from the magnet.
Industry:Aviation
A protection device for electrical circuits that carry large amounts of current. The housing containing the current-carrying contacts is filled with oil which quenches the arc that forms as the contacts open. Quenching the arc prevents damage to the contacts when they open a circuit carrying a large amount of current.
Industry:Aviation
A protective covering wrapped around flexible hoses installed in the engine compartments of an aircraft. A fire sleeve does not increase the service temperature of the hose, but it protects the hose from direct fire long enough to allow appropriate action to be taken.
Industry:Aviation
A protective frame at the tail of a single-rotor helicopter used to protect the tail rotor from damage during ground operation.
Industry:Aviation
A publication designed primarily as a pilot’s preflight planning guide for flights into foreign airspace and for flights returning to the U.S. from foreign locations.
“If no transmission received for (time)” (air traffic control). A phrase used by ATC in radar approaches to prefix procedures which should be followed by the pilot in event of lost communications.
Industry:Aviation
A publication issued every 14 days, designed primarily for the pilot, which contains current NOTAM information considered essential to the safety of flight as well as supplemental data to other aeronautical publications. The contraction NTAP is used in NOTAM text.
N-type semiconductor material. A semiconductor element, such as silicon or germanium, doped with an element having more electrons in its valence shell than are needed to complete the covalent bonds within the material. There are electrons in N-type material that are free to move about. Silicon and germanium are doped with a pentavalent element, such as arsenic or phosphorus, to make N-type material.
Industry:Aviation
