Fuel transfer pump

"rmhou at yahoo.com" wrote in message
ups.com...
I want to add an aux tank & transfer fuel to main tank with a pump
during flight. I think it makes fuel management easier if the pump
transfer close to the engine's burn rate, say 14 gph.

Here's a recommendation for wiring. Use a timer switch as is used for
bathroom fans. It has several advantages:
1. It is not likely to be confused with any other switch.
2. You can set it for an interval which will never overfill your main tank
from the aux.
3. You can't forget to turn it off.
4. Your electric pump can transfer fuel faster than, say 14 gph, without a
problem.

Rich S.

"Rich S." wrote

Here's a recommendation for wiring. Use a timer switch as is used for
bathroom fans. It has several advantages:
1. It is not likely to be confused with any other switch.
2. You can set it for an interval which will never overfill your main tank
from the aux.
3. You can't forget to turn it off.
4. Your electric pump can transfer fuel faster than, say 14 gph, without a
problem.

I like the idea. I would want to see an over-ride, as a backup.

Bathroom fan switches are "not quite" up to aerospace quality standards.

How is this one, too?

Put the transfer pump running off of a relay, that is hooked to a "full
tank" sensor. Even if you used a timer, like above, it would prevent an
over flow situation - if you set the timer for too long, too soon.
--
Jim in NC

"Morgans" wrote in message
...

Bathroom fan switches are "not quite" up to aerospace quality standards.

Used the way it should be, failure of the switch shouldn't be a factor.

Put the transfer pump running off of a relay, that is hooked to a "full
tank" sensor. Even if you used a timer, like above, it would prevent an
over flow situation - if you set the timer for too long, too soon.

What was that quote about idiots and failures? I can't remember right now
but one cannot idiot-proof everything. I think adding a "full tank" sensor
would be overkill. The setup in the Emeraude I had (which went in killing
the pilot because of completely empty tanks) had a 20 gallon main and a 5
gallon aux tank. When the main got down to half, one would crank the "fan
switch" over to it's stop and it would dump the five gallons into the main
and then shut off, saving the pump and battery for the next time.

A simple setup and one designed to save the pilot's brains from overload so
he can deal with the lowering overcast he just flew into.



Rich S.

Rich S. wrote:
snip

What was that quote about idiots and failures? I can't remember right now
but one cannot idiot-proof everything.

Probably a variation of "when someone invents an idiot proof device
someone else will invent a better idiot.

Dan, U.S. Air Force, retired

"Morgans" wrote in message
...

Bathroom fan switches are "not quite" up to aerospace quality standards.

Have you ever had a bathroom fan switch failure? That's got to be ugly.

Rich (where's the match? hack,hack) S.