Fuel load - different tanks

[Bozon12]

on some planes (p47 and f6f that bother me), when on auto fuel management, the aux fuel is burnt first and then the other tanks.
If you take a p51 and load it with 50% in the hangar, you'll get an empty aux, and little more than half on LW/RW - makes sense.
but on f6f and p47 it's not like that. if you load it with 50% it loads 50% in all tanks including the aux. I've been told that having fuel in the aux, hampers the planes preformance, so I always try to burn it early.

two questions:
1. does it matter?
2. If answer to 1 is YES, then why is it like that?

Bozon

[MANDOBLE]

Good point Bozon.
My personal answers:
1 - Yes, of course.
2 - No idea.

[Tac]

1. Yes, most definetely.
2. If the Q. is why the aux tank hampers performance: I believe its due to the center of gravity of the plane. A 190 with the AFT tank full is a squeak to fly, but if you empty it first, it becomes real sweet.

[Bozon12]

Tac,
thx, I know why it's like that, I ment to ask why it filles the aux tanks before main/wing tanks are full, like in the jug/hellcat and unlike in the p51.

currently what i do is take 75% and DT, burn most of the aux fuel and then switch to the DT. just seemed silly to me.

Bozon

[ 12-28-2001: Message edited by: Bozon ]

[Tac]

Yeah , its strange why the aux tanks get fuel when the main tanks arent full.

Maybe in the future HTC will let us fill the gas tanks as we want them to be.  

[Sancho]

The jug is supposed to drain aux fuel first, due to throwing off the center of gravity.  In fact there is a placard on the P-47 instrument panel reminding the pilot do use aux fuel first.  However, in some P-47 groups it was SOP to switch to main fuel before entering combat.  This way the pilot wouldn't have to worry about switching tanks in the middle of a fight (it wasn't automatic in real life) and would have a little extra auxiliary fuel left in case the main tank was hit and was unable to reseal itself.

I don't find that burning auxiliary fuel first in the AH jug makes a huge difference in flight characteristics.  Usually I burn up half the aux tank then sip on the main tank for the rest of the fight, keeping the aux in reserve.  This has gotten me home many times in AH when my main tank got hit, which for me happens 90% of the time when a fuel tank is damaged.  YMMV.

[Seeker]

HT's said many times that the fuel is set to both fill and empty while keeping the centre of gravity in the correct position for stable level flight.

This is quite normal practise, and is what any GA pilot would do.

However.... fuel can also be used as ballast, as every commercial pilot knows, and furthermore, there are some planes which benefit being in certain unstable configurations (the 190 being one of them) by having quicker, more responsive handling. The flip side is that should you lose the plane, you'll be trying to recover a plane with an unstable configuration, which can be tough.

Try the same trick on a 205, and you can get some nasty surprises.

[Bozon12]

HT's said many times that the fuel is set to both fill and empty while keeping the centre of gravity in the correct position for stable level flight.  

doen't any make sense.
If you take 100% fuel, auto fuel management will dry the aux tank the switch to main (lw/rw in hellcat). I this keeps the CG then when you take 75% it should fill the main tank completly and about 20% in the aux. Instead it fills all the tanks with 75%.

personally I didn't notice any real change in preformance, but I suck in the jug so I wouldn't know. And in the hellcat, which i'm very fond of, aux fuel burns so quickly it doesn't matter.

thx for the replys btw.
Bozon