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A10Warthog
4th Aug 2008, 08:48
Hello.
Why can you not x-feed with both engines operating? In POH "only x-feed with one engine inop."
On King air 200 ?

Dream Land
5th Aug 2008, 04:18
The system seems to be set up for more of an automatic operation, via the three position switch. I can't answer your question specifically, maybe this paragraph will help you come up with the answer.

(4) Fuel crossfeed switch. The fuel crossfeed valve is controlled by a 3-position switch, located on the fuel
management panel, placarded CROSSFEED - OFF. Under normal flight conditions the switch is left in the OFF
position. During single engine operation, it may become necessary to supply fuel to the operative engine from
the fuel system on the opposite side. The crossfeed system is placarded for fuel selection with a simplified
diagram on the overhead fuel control panel. Place the standby fuel pump switches in the off position when
crossfeeding. A lever lock switch, placarded CROSSFEED, is moved from the center OFF position to the left or
to the right, depending on direction of fuel flow. This opens the crossfeed valve and energizes the standby pump
on the side from which crossfeed is desired. During crossfeed operation, auxiliary tank fuel will not crossfeed if
the FUEL FIREWALL valve is closed. When the crossfeed mode is energized, a green FUEL CROSSFEED
light on the caution/advisory panel will illuminate. The crossfeed valve is protected by a 5-ampere circuit
breaker placarded CROSSFEED VALVE located on the overhead circuit breaker panel

Apparently the STBY pumps in conjunction with the CROSSFEED switch only work when in the OFF position, let me know what you think.

King Air 200, great airplane! :ok:

ahramin
9th Aug 2008, 02:31
Each engine in the BE20 is fed from its respective fuel tank by an engine driven low pressure fuel pump. If this pump fails then the engine is fed by the standby electric boost pump. Each standby electric boost pump has a switch to turn it on.

The crossfeed system operates by placing the crossfeed switch to the position of the engine which is to be fed from both tanks. If the crossfeed switch is placed in the left position the crossfeed valve opens and the right electric boost pump activates. However, if this is done with the right engine still operating most if not all of the fuel provided by the right electric boost pump will be sent to the right engine by its engine driven low pressure fuel pump. So no crossfeed happens even though the valve is open because each tank is still feeding its respective engine like before.

But with a max fuel imbalance of 1000 pounds, this is not an issue.

If this is not clear let me know and I will post the system diagram.

mad2fly
14th Aug 2008, 16:09
The King Air 200 crossfeeds just fine with both engines running. The problem is some fool wanted to balance the fuel and forgot the switch in the crossfeed position. The result was an engine loss during a critical phase of flight.

So, the lawyers got involved and made Beechcraft put that limitation in.