曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
compound called aluminum nitride.
Case hardening is used on such steel parts as engine crankshafts. Only the surfaces where the
bearings ride are made very hard and brittle. The inside of the crankshaft remains tough and strong.
casein glue. A form of powdered glue made from milk. Casein glue powder is mixed with cold water to
form a creamy paste.
Printed from Summit Aviation's Computerized Aviation Reference Library, 2/7/2007
Page 109
Casein glue was formerly used for joining wood parts of aircraft, but it is no longer used because
better types of glue are now available.
case pressure (fluid pump pressure). A relatively low pressure maintained inside the bearing cavities of
an engine-driven hydraulic pump.
If the shaft or the bearings (bushings) of the pump should become damaged, case pressure will
force hydraulic fluid out of the pump, rather than allowing air to be pulled in.
casing (aircraft tire component). The rubber and fabric body of a pneumatic tire. The casing is the same
as the carcass of the tire.
casing nail. A form of wire nail made of smaller gage wire than that used for a common nail of the same
length.
castellated nut. A form of hexagonal nut (a six-sided nut) that has slots cut across its end. A cotter pin is
passed through the slots and through a hole in the shank of the bolt to lock the nut to the bolt. Castellated
nuts are often called castle nuts.
casting. A method of forming an object by pouring molten metal or liquid plastic resin into a mold. The
material is allowed to harden inside the mold and, when hard, it is removed. Castings are less expensive
than forgings, but they usually have much less strength. Reciprocating engine crankcases are normally
castings.
cast iron. Iron that contains carbon and silicon. Cast iron is heavy, brittle, and hard, and cannot be formed
by forging. It is used for making objects that do not require a great deal of strength and can be made by
pouring the molten iron into molds.
The main use of cast iron in aircraft technology is in the manufacture of piston rings for
reciprocating engines.
CAT (clear air turbulence). Extreme turbulence found at high altitude. Clear air turbulence is created
when a difference in the temperature causes a violent movement of the air.
CAT cannot be seen, because there is no moisture at the altitude at which it occurs. In the lower
altitudes, where there is moisture, turbulence in the air causes recognizable cloud patterns.
catalyst. A substance used to change the speed or rate of a chemical action without being chemically
changed itself.
Water functions as a catalyst in the process of iron turning into rust (iron oxide). Dry iron does not
rust nearly as fast as iron with water on its surface. The water itself is not affected, but the iron unites with
oxygen from the air to become iron oxide, or rust.
catalytic cracking (petroleum refining). A method of refining petroleum products. In catalytic cracking, a
catalyst is used to change high-boiling-point hydrocarbons into low-boiling-point hydrocarbons.
catapult. A mechanism used to hurl, or launch, an object at a high rate of speed. Catapults are used to
launch heavily loaded aircraft from the decks of aircraft carriers.
category (aircraft classification). 14 CFR Part 1:
“(1) As used with respect to the certification, ratings, privileges, and limitations of airmen, means
a broad classification of aircraft. Examples include: airplane; rotorcraft; glider; and lighter-than-air; and
(2) As used with respect to the certification of aircraft, means a grouping of aircraft based upon
intended use or operating limitations. Examples include: transport, normal, utility, acrobatic, limited,
restricted, and provisional.”
Category A. 14 CFR Part 1: “With respect to transport category rotorcraft, means multiengine rotorcraft
designed with engine and system isolation features specified in Part 29 and utilizing scheduled takeoff and
landing operations under a critical engine failure concept which assures adequate designated surface area
and adequate performance capability for continued safe flight in the event of engine failure.”
Category B. 14 CFR Part 1: “With respect to transport category rotorcraft, means single-engine or
Printed from Summit Aviation's Computerized Aviation Reference Library, 2/7/2007
Page 110
multiengine rotorcraft which do not fully meet all Category A standards. Category B rotorcraft have no
guaranteed stay-up ability in the event of engine failure and unscheduled landing is assumed.”
Category II operations. 14 CFR Part 1: “With respect to the operation of aircraft, means a straight-in ILS
approach to the runway of an airport under a Category II ILS instrument approach procedure issued by the
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
航空术语词典Dictionary of Aeronautical Terms 上(73)
