Warbird Information Exchange

I OWN A BT-13A AND I NEED A LITTLE HELP IN SETTLEING AN ON GOING HANGER ARGUMENT. HERES THE QUESTION:

IS IT POSSIBLE TO RUN THE 17 GALLON RESERVE OUT WITH FUEL STILL IN THE RIGHT HAND MAIN TANK AND THE SELECTOR ON RESERVE. IF THE ANSWER IS NO THEN WHY HAVE A RIGHT TANK POSITION ON THE SELECTOR AT ALL OR AT LEAST WHY USE IT. THIS MAY SEEM SILLY TO SOME PEOPLE BUT THAT RIGHT TANK AND SELECTOR VALVE HAVE PUT MORE 13S IN THE DIRT THAN ANY ONE OTHER SINGLE ITEM AND WE REALLY DON'T KNOW THE ANSWER TO THE QUESTION. I AM BETTING THAT THERE ARE A LOT OF PEOPLE FAMILIAR WITH YOUR SITE THAT DO KNOW THE ANSWER AND WOULD SHARE IT IF WE KNEW HOW TO ASK THEM. THANKS BILL

If I remember correctly, the only way that you can run it dry with the selector on Reserve and have fuel in the Main, is to physically swap the fuel standpipe connections at the tank. This would cause you to be selecting the lower level reserve standpipe as the main feed.

Of course, with the fuel level low enough and enough right bank or slip, it's possible to unport both pickups.

Hi Paul,

The logic behind the system installation (as I understand it) is this:

The airplane holds 120 US gallons in two wet-wing type tanks, left and right, each holding 60 gallons. The fuel selector is marked "left", "right", and "reserve". With the selector on the left tank the airplane will drain the left wing tank completely of useable fuel. With the selector on the right tank the airplane will use the first 43 gallons in the right wing and then suck air. With the right tank full and the selector on "reserve" the airplane will use the entire right hand tank's useable quantity of fuel (same as it will with the selector on "left" and the left tank being full.) The logic to it is two-fold; If the right hand tank is full and you takeoff with "right" selected on the fuel selector you aren't very likely to pick up any water off the bottom of the tank were you to have any as the standpipe for the "right" selection is 17 gallons higher than "reserve", and two, if you're flying along enroute and using only the "left" and "right" positions on the selector to manage your fuel, if that little red light at the top of the instrument panel were to come on ("low fuel pressure") with the left tank empty and the selector on right, you'd still have 17 gallons to find a place and land.

Now normally you'd be more on top of your fuel situation than that but as someone with a fair ammount of time in a DH Beaver (three tanks, one selector, two fuel pumps and a big red light) I can attest to having been guilty in the past of being "fat, dumb, and happy" and then suddenly being awoken from my stupor by that BIG red light on top of the dash! (sometimes I even managed to change tanks and get on the wobble pump before the big Pratt quit!)

That's the way I understand the system to work anyway but I haven't physically gotten into the fuel system on my project yet - I'm still burning holes in my shirt with the sparks from the welding torch.

cheers,
Dan

I think that some versions of the T-6 also have this standpipe/reserve feature.