FAA Engine Fuel and Fuel Metering Systems (4)

How will the mixture of an engine be affected if the bellows of the automatic mixture control (AMC) in a pressure carburetor ruptures while the engine is operating at altitude?. It will become leaner. No change will occur until the altitude changes. It will become richer.

When an electric primer is used, fuel pressure is built up by the. internal pump in the primer solenoid. suction at the main discharge nozzle. booster pump.

Most large aircraft reciprocating engines are equipped with which of the following types of engine-driven fuel pumps?. Rotary vane-type fuel pump. Centrifugal-type fuel pump. Gear-type fuel pump.

Kerosene is used as turbine engine fuel because. kerosene has very high volatility which aids in ignition and lubrication. kerosene has more heat energy per gallon and lubricates fuel system components. kerosene does not contain any water.

An aircraft engine continuous cylinder fuel injection system normally discharges fuel during which stroke(s)?. Intake. Intake and compression. All (continuously).

What effect does high atmospheric humidity have on the operation of a jet engine?. Decreases engine pressure ratio. Decreases compressor and turbine RPM. Has little or no effect.

Which type of fuel control is used on most of today's turbine engines?. Electromechanical. Mechanical. Hydromechanical or electronic.

A rotary-vane pump is best described as a. positive-displacement pump. variable-displacement pump. boost pump.

The metered fuel pressure (chamber C) in an injection-type carburetor. ls held constant throughout the entire engine operating range. varies according to the position of the poppet valve located between chamber D (unmetered fuel) and chamber E (engine-driven fuel pump pressure). will be approximately equal to the pressure in chamber A (impact pressure).

During the operation of an aircraft engine, the pressure drop in the carburetor venturi depends primarily upon the. air temperature. barometric pressure. air velocity.

A punctured float in a float-type carburetor will cause the fuel level to. lower, and enrich the mixture. rise, and enrich the mixture. rise, and lean the mixture.

If the volume of air passing through a carburetor venturi is reduced, the pressure at the venturi throat will. decrease. be equal to the pressure at the venturi outlet. increase.

Where is the engine fuel shutoff valve usually located?. Aft of the firewall. Adjacent to the fuel pump. Downstream of the engine-driven fuel pump.

Fuel pump relief valves designed to compensate for atmospheric pressure variations are known as. compensated-flow valves. pressurized-relief valves. balanced-type relief valves.

Maximum power is normally considered to be developed in a reciprocating engine with a air-fuel mixture ratio of approximately. 8:1. 12:1. 15:1.

What carburetor component measures the amount of air delivered to the engine?. Economizer valve. Automatic mixture control. Venturi.

A mixture ratio of 11:1 normally refers to. a stoichiometric mixture. 1 part air to 11 parts fuel. 1 part fuel to 11 parts air.

Which of the following statements is true?. A positive displacement pump produces a continuous flow, but due to lack of a positive internal seal against slippage, its output will increase as pressure increases. In a positive displacement pump, slippage is substantial compared to the pump's volumetric output flow. If the output port were plugged, pressure would increase, and the pump pressure relief valve would close. In a positive displacement pump, slippage is negligible compared to the pump's volumetric output flow. If the output port were plugged, pressure would increase, and the pump pressure relief valve would open.

Fuel pressure produced by the engine-driven fuel pump is adjusted by the. bypass valve adjusting screw. relief valve adjusting screw. engine-driven fuel pump adjusting screw.

In order to stabilize cams, springs, and linkages within the fuel control, manufacturers generally recommend that all final turbine engine trim adjustments be made in the. increase direction. decrease direction. decrease direction after over- adjustment.

One of the things a metering orifice in a main air bleed helps to accomplish (at a given altitude) in a carburetor is. pressure in the float chamber to increase as airflow through the carburetor increases. a progressively richer mixture as airflow through the carburetor increases. better fuel vaporization and control of fuel discharge, especially at lower engine speeds.

Select the correct statement concerning the idle system of a conventional float-type carburetor. The low-pressure area created in the throat of the venturi pulls the fuel from the idle passage. Climatic conditions have very little effect on idle mixture requirements. The low pressure between the edges of the throttle valve and the throttle body pulls the fuel from the idle passage.

A full-authority electronic engine control (EEC) is a system that receives all the necessary data for engine operation and. adjusts a standard hydromechanical fuel control unit to obtain the most effective engine operation. develops the commands to various actuators to control engine parameters. controls engine operation according to ambient temperature, pressure, and humidity.

What causes the fuel divider valve to open in a turbine engine duplex fuel nozzle?. Fuel pressure. Bleed air after the engine reaches idle RPM. An electrically operated solenoid.

In turbine engines that utilize a pressurization and dump valve, the dump portion of the valve. cuts off fuel flow to the engine fuel manifold and dumps the manifold fuel into the combustor to burn just before the engine shuts down. drains the engine manifold lines to prevent fuel boiling and subsequent deposits in the lines as a result of residual engine heat (at engine shutdown) . dumps extra fuel into the engine in order to provide for quick engine acceleration during rapid throttle advancement.