I just came across a notation I made quite a while ago, after noticing
a neat idea, probably on this list.
It utilizes a low pressure switch to provide an "automatic" mode to
the electric fuel boost pump, so that if the engine driven pump
failed, the electric one would be powered up.
This seemed like a great idea at the time. It would likely mean an
engine hiccup, followed by the fuel pump on LED illuminating - much
better than the pilot conjecturing the engine failure is due to fuel
starvation and manually turning on the pump (would be a checklist item).
However, looking at the schematic as I drew it, as soon as the
electric pump provided sufficient pressure, the low pressure switch
would open and the pump would shut off, and then back on, and then
off. Ooops :-(
Is it worth fabricating a little latching circuit to provide this
automatic operation, or better to keep things simple ?
I don't do hard IFR, and manually turning on the fuel pump switch in
most circumstances would be sufficient to avoid an unpleasant landing.
Thoughts ?
Jeff Page
Dream Aircraft Tundra #10
