Bob Darrah wrote:

I plan on using a fuel pump connected to each main tank and the tank
selected will be by which pump is turned on.  In addition, it will  have
in the return line, an old style automotive electric selector valve wired
to one of the pumps.  The kind that when it has power the return
goes one way and when the power is off, it goes the other way .
When that pump is on, the return is back to that tank (even if both
pumps are on) and when only the other pump is on, it will be
returned to the other tank.
Failure mode:  all fuel returned to the same tank.  And  rubber fuel
line is required to make the connection.

Added advantage, turbulence in the tank to keep the oil stirred up.

If any one can shoot holes in this idea, please do it now so that it will
save me a lot of work (and maybe my behind)

Bob Darrah

Jim Sower wrote:

My vote would be to substitute for your switch a bi-directional transfer pump
that you manage yourself in the event of injection pump failure.  Your way
seems to abandon the remaining fuel in the tank containing the 'dead' pump.
This notion does assume that: a) You are aware that you have an injection pump
failure; b) You know which pump has failed; c) You remain sufficiently focused
for the remainder of the flight to adequately manage the transfer (turn it off
in the event of serious asymmetry) and so forth.  What would your 'electric
selector' do if there was power to a pump but it just wasn't doing anything, or
it was doing its best, but a clogged filter kind of nullified its efforts?  Or
a leaky/ruptured line was dumping fuel over the side (God forbid!)?
Just wonderin' ....  Jim S.

 
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