FUEL SYSTEM

Question 1

Volatility

Answer 1

is the measurement of a liquid’s ability to convert to a vaporous state. Fuel must vaporize and be mixed with a given percentage of air for it to burn or explode. The volatility of a fuel effects engine starting, range, and safety.

Question 2

A fuel’s volatility rating is fixed. This rating or scale is similar to other types of rating such as “octane,” atmospheric pressure, or even academic grades. A fuel with a_____ volatility rating will vaporize and then ignite more rapidly than a less volatile fuel.

Answer 2

high

Question 3

The lowest temperature of a combustible substance (fuel) that would ignite with a momentarily application of a flame is its __________. A ________ point and volatility rating are inversely related. As the fuel’s volatility rating increases, the flash point of the fuel decreases

Answer 3

flash point

fuel’s flash

Question 4

Kerosene’s use as a fuel additive, why?
1
2

Answer 4

1 Reduce freeze potential.

2 flash point for kerosene is higher than gasoline, making it more stable

Question 5

FUEL TANKS

Answer 5

The tank is a reservoir, or holding cell, for the jet propellant. Fuel tanks, as well as any fuel system, are normally made of materials that will not react chemically with any fuel. Most fuel tanks are made of synthetic rubber with self-sealing cells called bladders that fit into cavities in the wing or fuselage of the aircraft

Question 6

The boost pump is an integral unit composed of a centrifugal pump and electric motor. Submerged and installed in the fuel tanks. they ensure an adequate supply of fuel to the ________________.

Answer 6

engine-driven fuel pump

Question 7

BOOST PUMP FUNCTIONS.

Answer 7

1. they ensure an adequate supply of fuel to the engine-driven fuel pump
2. It may also be used to transfer fuel from one tank to another tank for proper weight and balance
3. Boost pumps are needed to supply fuel pressure for starting engines and to supply fuel to the primer system
4. A critical function of the boost pump is to prevent aeration of the fuel supply which may result from a rapid pressure change incurred during a climb
   In extreme cases these bubbles may induce vapor lock or cavitation of the engine-driven pump.
   The boost pump supplies the fuel under pressure to the main fuel pump, reducing or eliminating the effects of aeration

Question 8

The engine-driven pump is a high pressure pump. It is designed to deliver fuel to the fuel control unit. This pump provides fuel in excess of engine requirements. The excess fuel ensures that a sufficient supply of high pressure fuel is available to meet ______ requirements

Answer 8

engine

Question 9

The fuel control unit (FCU) is the “brain” of the engine fuel system. The FCU is a hydromechanical or electrical device that consists of fuel computing and fuel metering systems. It is designed to send ‘metered fuel’ (measured fuel) to satisfy fuel-flow requirements for ______________.

Answer 9

starting, acceleration, deceleration, and stabilized (steady state) operation

Question 10

The fuel-oil cooler is a heat exchanger designed to preheat metered fuel and cool the engine lubricant as it flows from the engine. Preheating fuel removes any __________ and increases its volatility. facilitating efficient fuel ignition

Answer 10

ice crystals

Question 11

The fuel manifold delivers fuel to the engine burner section through a series of _________.

Answer 11

fuel nozzles

Question 12

From the fuel tank to the _________ through the ______________ through the filter to the _________ fuel pump through the __________ to the flowmeter to the fuel-oil heat exchanger into the manifolds and into the engine

Answer 12

boost pump

emergency fuel shutoff

engine driven

fuel control unit