Van's Air Force
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Extra fuel
- Thread starter brister
- Start date
N941WR
Legacy Member
Yes, it has been done before.
I just jad this discussion with another member of this forum last night.
Here is what we discussed:
1. Decide how much extra fuel you want. Then divide 18 by the number of bays in the tank and cut it down to meet your requirements.
2. Make the entire piece of leading edge that will bridge the two tanks removable rather than just adding an access plate.
3. Do the RV-10/Rocket coil for the vent line outboard of the tank and poke it out the bottom of the wing.
4. Getting the fuel to the engine is a bigger debate than the nay sayers will have about adding these tanks. You can add electric fuel pumps to move the outboard fuel to the onboard tanks. My favorite idea is to buy a valve (Andair?) that has five positions (Left outboard, left inboard, off, right onboard, and right outboard). That is the simplest to plumb and doesn't require the complexity of fuel pumps, wiring, fueses, etc.
Good luck and please report back with your configuration.
I just jad this discussion with another member of this forum last night.
Here is what we discussed:
1. Decide how much extra fuel you want. Then divide 18 by the number of bays in the tank and cut it down to meet your requirements.
2. Make the entire piece of leading edge that will bridge the two tanks removable rather than just adding an access plate.
3. Do the RV-10/Rocket coil for the vent line outboard of the tank and poke it out the bottom of the wing.
4. Getting the fuel to the engine is a bigger debate than the nay sayers will have about adding these tanks. You can add electric fuel pumps to move the outboard fuel to the onboard tanks. My favorite idea is to buy a valve (Andair?) that has five positions (Left outboard, left inboard, off, right onboard, and right outboard). That is the simplest to plumb and doesn't require the complexity of fuel pumps, wiring, fueses, etc.
Good luck and please report back with your configuration.
LifeofReiley
Well Known Member
Yes Sir...
http://www.vansairforce.com/community/showthread.php?t=40019
Sorry... someone dumped the post.
http://www.vansairforce.com/community/showthread.php?t=40019
Sorry... someone dumped the post.
eh_v8_tor
Active Member
Fuel = weight consider lateral C of G
Hi Dean,
I hate to be the devil's advocate here. Personally I considered making long range fuel tanks. I decided against it since we have short range bladders and a few other factors that boils down to not wanting to push the envelope too much.
With a whole bunch of extra weight out near the wing tips one would have to think about the handling characteristics of the aircraft. Most worrisome would be the question "would it be possible to recover from a spin with all the extra mass outboard like that?" Correct me if I'm wrong but I believe this is why the RV 7 has a bigger rudder.... People were using heavier engines than recommended by Vans, so he made the rudder bigger for spin recovery, also the RV7 has a bit more fuel than the RV6 putting more mass outboard.
How would it handle? Like a zippy RV or a sluggish pig?
I'm not saying that it can not be done, cause people have done it. Perhaps a chat with Vans is in order here to decide if it is something that you would really want to do.
Happy Building,
Steve Wolfe
P.S. I'm not an AME, just my cents worth to be sure you consider the center of gravity.
Hi Dean,
I hate to be the devil's advocate here. Personally I considered making long range fuel tanks. I decided against it since we have short range bladders and a few other factors that boils down to not wanting to push the envelope too much.
With a whole bunch of extra weight out near the wing tips one would have to think about the handling characteristics of the aircraft. Most worrisome would be the question "would it be possible to recover from a spin with all the extra mass outboard like that?" Correct me if I'm wrong but I believe this is why the RV 7 has a bigger rudder.... People were using heavier engines than recommended by Vans, so he made the rudder bigger for spin recovery, also the RV7 has a bit more fuel than the RV6 putting more mass outboard.
How would it handle? Like a zippy RV or a sluggish pig?
I'm not saying that it can not be done, cause people have done it. Perhaps a chat with Vans is in order here to decide if it is something that you would really want to do.
Happy Building,
Steve Wolfe
P.S. I'm not an AME, just my cents worth to be sure you consider the center of gravity.
pierre smith
Well Known Member
Nope
No need to call Van's....we already know their answer.
Jon Johannson had 15+ hours of fuel in his -4...300lbs. of that in the back seat!
Best,
No need to call Van's....we already know their answer.
Jon Johannson had 15+ hours of fuel in his -4...300lbs. of that in the back seat!
Best,
Staunch111
Well Known Member
And correct me of I'm wrong but the 7 and the 9 now have the exact same rudder
ifixf15
Active Member
Tuckey Tanks
Pat still has one of the more elegant solutions. KISS principle at work. Outboards always feed first ensuring that the lateral CG is diminishing until the outboards are empty. Transfer pump rounds out the belt and suspenders approach.
http://napwars.com/RV-8HTML/Fuel.htm
(Yes, I understand that actually fuel is drawn from the inboards and replaced by the outboards until the outboards are empty.)
Pat still has one of the more elegant solutions. KISS principle at work. Outboards always feed first ensuring that the lateral CG is diminishing until the outboards are empty. Transfer pump rounds out the belt and suspenders approach.
http://napwars.com/RV-8HTML/Fuel.htm
(Yes, I understand that actually fuel is drawn from the inboards and replaced by the outboards until the outboards are empty.)
