Current testing requirements for high temperature alloys are defined in general industry specifications (ASTM, AMS), as well as in user specifications. Many of these requirements were established in the 1960's when production practices were yet to be refined.
cowling - protective covering consisting of a metal part that covers the engine; there are powerful engines under the hoods of new cars; the mechanic removed the cowling in order to repair the plane's engine.
An idle air control valve, also called an idle air sensor control motor, is an electrically operated valve that controls the amount of air that bypasses the throttle plate in cars with a fuel injection system [source: Autozone ]. This causes the idling speed of the engine to change as needed.