Do you regularly run tanks (aux) dry?

When I did my Alaska flying, speaking to pilots en route, some recommended to fly as fast as possible and run the tank dry, if you suspect you are coming up short in fuel. Last thing you want is to run out of fuel with a few gallons left in the other tank.

I never came this close on the Alaska trip, I think I always landed with ~10gal or more fuel remaining. But I do keep that in mind in case of any diversions or negative wind changes.
 
In a A36 with tip tanks (and the 5 position selector), the fuel flow gauge gives you ample warning that the tank is empty. You know when it's going to happen so you just keep an eye on it and switch. The only downside is that now you have 8ft of air filled fuel line coming in from the tank, so you may have a little delay the next time you switch to the tips. Just make sure you do that in cruise and if you have pax, tell them that the engine may lose power for a few seconds until the air clears from the line.
Iirc there is a regulation that says the engine has to be able to restart within X seconds from an air filled line.
 
I read once that fuel in the top tracks is worth a few extra knots of cruise airspeed. Do you who have tip tanks experience that? Does that influence your choice to run the aux empty first?
 
I read once that fuel in the top tracks is worth a few extra knots of cruise airspeed. Do you who have tip tanks experience that? Does that influence your choice to run the aux empty first?
Cherokee six POH...
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Routinely used to burn the aux tanks dry in my 310. Only once did both engines actually burn them down so equally there was some really rapid selector turning!
 
I read once that fuel in the top tracks is worth a few extra knots of cruise airspeed. Do you who have tip tanks experience that? Does that influence your choice to run the aux empty first?
Not that I've noticed. The advantage of tip tank fuel is it doesn't count against your gross in my plane (You get an increase in gross weight over 2860 provided all the additional weight is in the tips).
 
Here's the AVWEB (it was Deakin) on the subject:


Very good read. Thanks for sharing.
 
I always figured that if a fuel selector were going to fail it would probably be right after you ran a tank dry.
If it fails halfway through switching, does it really matter if a tank is dry?

All kidding aside: I do believe it is prudent to think about the (unlikely, yes) possibility of a fuel issue from attempted tank switching, and select the time of switching tanks appropriately - such as when in gliding distance of a runway. That is true whether one runs a tank dry or not.

- Martin
 
Does your plane have a fuel pressure gauge? Flow meter? Something like that could give you a few seconds warning before the engine goes quiet.

In the beaver there is a fuel pressure light and when it turns on you have 5 seconds to switch tanks and wobble wobble wobble or you definitely aren’t getting a tip from your fishing clients.
 
Routinely used to burn the aux tanks dry in my 310. Only once did both engines actually burn them down so equally there was some really rapid selector turning!
Same for me, and mine run down at wildly different rates. The 310 makes aux fuel particularly important to get out of the tanks, because only the mains are available for cross-feed. If you lose an engine, the fuel in the aux tank next to it is dead weight.
 
I ran the aux tank dry one time when I had my Cherokee 6. I knew it was coming but my wife, who was asleep did not. I didn't know my wife could levitate but when the engine stumbled, she came alive like a woman possessed. From then on out I always left 1 gallon in the tank according to the fuel flow meter.

In my 310Q, I do the same. In my 421C we have nacelle aux tanks that don't have a gauge. They flow directly into the mains so no worries there.

I have a 2 hour butt or a 2 hour bladder. Which ever comes first. I refuse to use the relief tube at the back of the plane in the 421.
 
Margy turned the fuel selector from AUX to OFF on downwind one day. That woke me up in a hurry.
 
Haven't read the whole thread but I've never run my tanks dry and hopefully never will. I'm on the extremely paranoid side of the spectrum in terms of fuel planning.
 
My old bonanza had two aux tanks. I always ran them dry as there wasn’t a scavenger pump. IMO every gallon left in an aux tank is unusable.
 
My Mooney aux tanks flow into the main tanks, so they always get run dry.

If I am really tight on fuel, I will run one main dry so that I have all my fuel in one tank rather than split between the two.
 
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