PPLANT 2 - QUIZ 3 Reviewer

Electric starter

is usually a direct current (D.C.) electric motor coupled to the engine through a reduction gear and ratchet mechanism.

Cartridge starting

sometimes used on military engines and provides a quick independent method of starting.

Isopropyl-Nitrate Method of Starting

provides a high power output and gives rapid starting characteristics. It has a turbine that transmits power through a reduction gear to the engine.

Air Method of Starting

air starter motor transmits power through a reduction gear and clutch to the starter output shaft which is connected to the engine.

Gas turbine Method of Starting

The starter consists of a small, compact gas turbine engine, usually featuring a turbine driven centrifugal compressor, a reverse flow combustion system and a mechanically independent free-power turbine.

High-energy (H.E.) ignition

is used for starting all jet engines and a dual system is always fitted.

Relighting

The jet engine requires facilities for relighting should the flame in the combustion system be extinguished during flight. However, the ability of the engine to relight will vary according to the altitude and forward speed of the aircraft.

Fuel system

is one of the more complex aspects of the gas turbine engine. It must be possible to increase or decrease the power at will to obtain the thrust required for any operating condition.

Rich blowout

occurs when the amount of oxygen in the air supply is insufficient to support combustion and when the mixture is cooled below the combustion temperature by the excess fuel.

Fuel nozzles

form part of the fuel system and atomize or vaporize the fuel so that it ignites and burns efficiently Fuel Nozzle

Electronic fuel control unit (EFCU) (same as an EEC)

performs the functions of thrust setting, speed governing and acceleration, and deceleration limiting through EFCU outputs to the fuel control assembly in response to power lever inputs.

Filter bypass valve

in the fuel pump allows fuel to bypass the fuel filter when the pressure drop across the fuel filter is excessive.

Flow Divider And Drain Valve Assembly

drains the nozzles and manifolds at engine shutdown. It also incorporates an integral solenoid for modifying the fuel flow for cold-starting conditions.

Fuel manifold assembly

is a matched set consisting of both primary and secondary manifolds and the fuel nozzle assemblies.

These engine driven fuel pumps may be divided into two distinct system categories

1. Constant displacement

2. Nonconstant displacement

Combustion chamber drain valve

drains fuel that accumulates in the combustion chamber after each shutdown and fuel that may have accumulated during a false start.