then sent to the fuel-metering valve on the air-induction system throttle body,
which adjusts fuel flow in response to the pilot controlled lever position. From the
metering valve, fuel is directed to the fuel manifold valve (spider) and then to the
individual injector nozzles.
112. Describe the electric fuel pump operation? It’s an oil pressure based system
that allows the pump to run at high speed (PRIME) when engine oil pressure is
less than 10 psi. Above 10 psi, PRIME has no effect. BOOST energizes the
pump in the low-speed mode regardless of oil pressure in order to provide
continuous fuel flow for vapor suppression in a hot fuel condition.
113. Where is the friction control wheel located? On the right side of the console.
114. How does the power lever (throttle) function? It adjusts the engine throttle
setting in addition to automatically adjusting propeller speed.
115. The power lever system is set to maintain what rpm? Approximately 2,500
rpm throughout the cruise power settings and 2,700 rpm at full power.
116. How does the mixture control lever function? It is mechanically linked to the
mixture control valve in the engine driven fuel pump and controls the mixture at
that point.
117. Which battery master switch activates the engine’s start/ignition switch? BAT
1.
118. Describe the function,location, and operation of the alternate air control knob:
It opens the alternate air induction door on the engine induction air manifold in
the engine compartment, bypasses the dry induction air filter, and allows warm
unfiltered air to enter the engine. It is located near the pilot’s right ankle on the
console. Depress the center lock button, pull to open, and then release the
button.
119. What will activate the engine oil warning light? High temperature or low
pressure.
120. How does the propellor system function? The propeller governor senses
engine speed by means of flyweights and senses throttle setting through a cable
connected to the power control lever (throttle). Moving the power lever forward
reduces governor oil pressure and allows centrifugal force to decrease propeller
Cirrus SR-20 POH Summary
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