Rub the surface with a clean cloth.

The turbine engines include compressor bleed systems used to control flow of air through the engine, cooling air systems, heated air systems for engine anti-icing, and engine starting systems.

The anti-icing system of the engine eliminates and prevents ice formation by bleed air in all parts of the engine (excluding power cowling), and is inclusive of several components such as valves, plumbing, regulators, etc.

The engine power control system furnishes a means of controlling the main fuel control or coordinator, which includes controls to the propeller regulator on turbo-prop engines.

Doors refer to those removable units used for entrance or exit, and for enclosing other structure contained within the fuselage, including passenger and crew doors, cargo doors, emergence exits, etc. Electrical and hydraulic systems associated with door control are included as appropriate.

Airborne Auxiliary Power are those airborne power plants (engines) which are installed on the aircraft for the purpose of generating and supplying a single type or combination of auxiliary electric, hydraulic, pneumatic or other power.

Vacuum subsystems are those units and components used to generate, deliver and regulate below atmospheric pressure air, including pumps, regulators, lines, etc., through and including the manifold.

Position Computing refers to that portion of the system which combines navigational information to compute the aircraft＇s geographical location, including items such as course computers, etc.

Independent Position Determining includes items such as inertial guidance systems, weather radar, doppler, proximity warning, collision avoidance, star tracker, etc. Also includes sextants/octants, etc.

Attitude & Direction section includes items such as gyro horizons, directional gyros, magnetic compasses, and magnetic heading systems, turn and bank, amplifiers, servos, and flight director, etc.

Flight Environmental Data & Pitot Static section includes items such as pitot, static, air temperature, rate-of-climb, airspeed, high speed warning, altitude, altitude reporting, altimeter correction system, etc.