Van's Air Force
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Bigger Tanks on RV-4??
- Thread starter Mopar591
- Start date
RV Wannabe
Well Known Member
http://www.safeair1.com/fueltanks.php
That is the best -4 option I know of for wings that are finished.
If you are still building search extended fuel. There is a long thread that discusses different ways. Tips that incorporate a tank, building an extra bay in the wing if you are still building wings and tanks, and then the safe air tanks. As far as I have read there is not currently an aftermarket tip tank for a -4. maybe in development?
Mark
That is the best -4 option I know of for wings that are finished.
If you are still building search extended fuel. There is a long thread that discusses different ways. Tips that incorporate a tank, building an extra bay in the wing if you are still building wings and tanks, and then the safe air tanks. As far as I have read there is not currently an aftermarket tip tank for a -4. maybe in development?
Mark
pierre smith
Well Known Member
Jon Johannsen in Australia had 18 hours worth of fuel in his -4 for the three Round-the-world flights!
Tip tanks were full plus a 50 gallon tank in the back seat area.
He had tip tanks for sale a while back, so you may Google them.
Best,
Tip tanks were full plus a 50 gallon tank in the back seat area.
He had tip tanks for sale a while back, so you may Google them.
Best,
he doesn't sell them anymore, that's a dead end road
this is your best bet for more fuel, i have the safeair1 ER tanks, they hold 4.5gallons per side, these hold 9.5 gallons per side
http://www.advancedaero.com/vans.html
I didn't go with them because of lead time and cost, but I will for the RV-7 I am building
this is your best bet for more fuel, i have the safeair1 ER tanks, they hold 4.5gallons per side, these hold 9.5 gallons per side
http://www.advancedaero.com/vans.html
I didn't go with them because of lead time and cost, but I will for the RV-7 I am building
RV Wannabe
Well Known Member
I stand corrected, looks like someone is building tips for a -4.
Not being a builder I have a question on the tips. Are these appropriate for a retrofit on a built airplane? How would one plumb the lines if the wings are finished? The rib you are sealing and bonding, is it part of the tip kit, or part of the wing you already have?
Thanks
Mark
Not being a builder I have a question on the tips. Are these appropriate for a retrofit on a built airplane? How would one plumb the lines if the wings are finished? The rib you are sealing and bonding, is it part of the tip kit, or part of the wing you already have?
Thanks
Mark
smokyray
Well Known Member
Short answer, yes!
Tyler,
Two current options for increasing RV4 fuel capacity.
1. During construction you can install RV6 wing tanks which hold 19 per side. Art Chard built a beautiful RV4 for my late friend and fellow Viper driver Brian Wolf. 39 total gallons is perfect for most folks. My friend "Tron's" RV4 has the aft portion of each wing center section sealed off rendering a bladder challenging 64 gallons total. This too has to be done during construction. Jon Johansen's tips are nice as well. However...
2. Post Construction: I installed a set of Hotel Whiskey's aux tanks in my RV4 bringing total up to 40 gallons. My RVX has RV4 wings (and tanks) so I installed a set in it and the total is 41.4 gallons. (My friend BW installed a set in Brian's former RV4, 50 gallons total) Hotel Whiskey Aviation's Safe Air One tanks cockpit-selectable feed uses no electrics and when empty place no G restrictions on the airframe.They increase capacity 10 gallons and only add 8.7 lbs of weight, at the spar. Home run modification.
Both of my RV's and Harmon Rocket have a set of their tanks installed. http://www.safeair1.com/fueltanks/rv4ertanks.php
Tell Hollywood and Cheese I said hey...
V/R
Smokey
Dues gladly paid in Iraq...
Gladly paid to DR anyway...
PS: Dave Anders placed a race car rubber bladder fuel tank in the baggage compartment of his RV4, adds 12 gallons with it's own pump and is self sealing!
Tyler,
Two current options for increasing RV4 fuel capacity.
1. During construction you can install RV6 wing tanks which hold 19 per side. Art Chard built a beautiful RV4 for my late friend and fellow Viper driver Brian Wolf. 39 total gallons is perfect for most folks. My friend "Tron's" RV4 has the aft portion of each wing center section sealed off rendering a bladder challenging 64 gallons total. This too has to be done during construction. Jon Johansen's tips are nice as well. However...
2. Post Construction: I installed a set of Hotel Whiskey's aux tanks in my RV4 bringing total up to 40 gallons. My RVX has RV4 wings (and tanks) so I installed a set in it and the total is 41.4 gallons. (My friend BW installed a set in Brian's former RV4, 50 gallons total) Hotel Whiskey Aviation's Safe Air One tanks cockpit-selectable feed uses no electrics and when empty place no G restrictions on the airframe.They increase capacity 10 gallons and only add 8.7 lbs of weight, at the spar. Home run modification.
Both of my RV's and Harmon Rocket have a set of their tanks installed. http://www.safeair1.com/fueltanks/rv4ertanks.php
Tell Hollywood and Cheese I said hey...
V/R
Smokey
Dues gladly paid in Iraq...
Gladly paid to DR anyway...
PS: Dave Anders placed a race car rubber bladder fuel tank in the baggage compartment of his RV4, adds 12 gallons with it's own pump and is self sealing!
Last edited:
AX-O
Well Known Member
I have a set of the Hotel Whiskey tanks. I like them alot. I have two self imposed limitation. Came out of the live and learn category.
1) Don't fill the aux tanks unless I can transfer all 8.2 gallons to the main tanks prior to landing.
2) Fill the aux tanks to the top or not at all.
It becomes difficult when taking off or landing if the fuel starts to slosh back and forward inside the tanks. I did it once and as soon as I took off I said "won't do that again". Same thing when I landed. That cheap fuel I wanted to take back home almost cause me alot of money.
With regards to the tip tank, I have a bud that made his own by glassing his wing tips. He can put about 8 gals in each side. He also does not fill them up unless he can burn the wing tip gas prior to landing. Approx 50 lbs on the tips are not un-noticeable.
1) Don't fill the aux tanks unless I can transfer all 8.2 gallons to the main tanks prior to landing.
2) Fill the aux tanks to the top or not at all.
It becomes difficult when taking off or landing if the fuel starts to slosh back and forward inside the tanks. I did it once and as soon as I took off I said "won't do that again". Same thing when I landed. That cheap fuel I wanted to take back home almost cause me alot of money.
With regards to the tip tank, I have a bud that made his own by glassing his wing tips. He can put about 8 gals in each side. He also does not fill them up unless he can burn the wing tip gas prior to landing. Approx 50 lbs on the tips are not un-noticeable.
I am in the beginning construction stages with the wings. I would prefer to enlarge the factory tanks with a Harmon rocket tank or rv6 tank vs a tip tank..
Can You elaborate on the rv6 tanks Smokeyray?
Rv Jerry. How hard is it to adapt the stock 4 wing to rocket tanks?
Can You elaborate on the rv6 tanks Smokeyray?
Rv Jerry. How hard is it to adapt the stock 4 wing to rocket tanks?
F1Boss
Well Known Member
Either way is easy: 3 options
You will have to decide which tank you want - either is easy to install. You will extend the tank attach flange during the spar assy process, and simply build a longer tank. BTW John Harmon can sell you 52 gal tanks if you want them.
I am not sure if the -8 tanks can be mated to the -4 style spar? I kinda doubt it, due to the Z-bracket requirement.
Then again, you could build 2 RV4 tanks for each side, and extend the tank attach flanges to fit this setup. This would call for some sort of transfer plumbing, or maybe a simple check valve. Best you use better filler caps on the inboard tanks if you go this gravity feed route.
Consideration: your max allowable gross weight will not change, so keep this in mind if your mission profile includes a back-seater and luggage.
Carry on!
Mark
You will have to decide which tank you want - either is easy to install. You will extend the tank attach flange during the spar assy process, and simply build a longer tank. BTW John Harmon can sell you 52 gal tanks if you want them.
I am not sure if the -8 tanks can be mated to the -4 style spar? I kinda doubt it, due to the Z-bracket requirement.
Then again, you could build 2 RV4 tanks for each side, and extend the tank attach flanges to fit this setup. This would call for some sort of transfer plumbing, or maybe a simple check valve. Best you use better filler caps on the inboard tanks if you go this gravity feed route.
Consideration: your max allowable gross weight will not change, so keep this in mind if your mission profile includes a back-seater and luggage.
Carry on!
Mark
pierre smith
Well Known Member
A friend of mine added half a tank skin to the two tanks, on their outboard ends, for his Super 8 with an IO-540 Lyc.
Buy a tank skin from Van, cut it in half and add each half to your existing tanks and cover your fuel filler hole and move it to the outboard end. I have a friend that can do this for you if you find it too challenging.
Best,
Buy a tank skin from Van, cut it in half and add each half to your existing tanks and cover your fuel filler hole and move it to the outboard end. I have a friend that can do this for you if you find it too challenging.
Best,
smokyray
Well Known Member
Cut that metal!
Sure Tyler,
You can purchase the RV6 (or Rocket) wing drawings. The RV6 tanks are 1/2 rib bay larger than the stock RV4 tanks. The RV6 wing drawings are a great guide as I found during construction of my RVX, the 4/6 wings are identical vice the inner rib bay and fuel tanks. My RVX utilizes RV4 wings and tail mated to a Six fuselage.
The Rocket wing drawings are excellent as well. Personally I would go with the RV6 tanks unless you like to fly longer than 4 hours at a time. My Rocket had 22 gallons per side plus the ER tanks (54 gallons). The HR2 tanks add 1/2 more rib bay to the 6 tanks.
The Hotel Whiskey(Safe Air One) ER tanks are great as they allow you to "tanker" fuel when you find it cheap or extend range when necessary. Otherwise you leave the valves closed until needed.
V/R
Smokey
Dues gladly paid in Iraq...
Gladly paid to DR anyway...
Sure Tyler,
You can purchase the RV6 (or Rocket) wing drawings. The RV6 tanks are 1/2 rib bay larger than the stock RV4 tanks. The RV6 wing drawings are a great guide as I found during construction of my RVX, the 4/6 wings are identical vice the inner rib bay and fuel tanks. My RVX utilizes RV4 wings and tail mated to a Six fuselage.
The Rocket wing drawings are excellent as well. Personally I would go with the RV6 tanks unless you like to fly longer than 4 hours at a time. My Rocket had 22 gallons per side plus the ER tanks (54 gallons). The HR2 tanks add 1/2 more rib bay to the 6 tanks.
The Hotel Whiskey(Safe Air One) ER tanks are great as they allow you to "tanker" fuel when you find it cheap or extend range when necessary. Otherwise you leave the valves closed until needed.
V/R
Smokey
Dues gladly paid in Iraq...
Gladly paid to DR anyway...
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pierre smith
Well Known Member
I don't.
I don't know of a thread, Tyler, but basically, after the new skin is cut in half, it is attached to the old skin with a piece of .025 aluminum underneath, joining the two pieces. You rivet an inner piece around the fuel-filler holes and a matching cover to close them off. BTW, all these seams are pro-sealed so that they don't leak fuel. You may need to shorten the original skins an inch or so, so that the piece joining the two skins doesn't fall on a rib.
As Smokey pointed out, the Rocket drawings should clarify this, or you could call John Harmon.
Best,
I don't know of a thread, Tyler, but basically, after the new skin is cut in half, it is attached to the old skin with a piece of .025 aluminum underneath, joining the two pieces. You rivet an inner piece around the fuel-filler holes and a matching cover to close them off. BTW, all these seams are pro-sealed so that they don't leak fuel. You may need to shorten the original skins an inch or so, so that the piece joining the two skins doesn't fall on a rib.
As Smokey pointed out, the Rocket drawings should clarify this, or you could call John Harmon.
Best,
longranger
Well Known Member
Tyler,
If you talk to John, ask him how long a tank skin he can bend for you, so you don't have to scab two skins onto the same tank. Back in the 1999-2000 time frame I believe he could bent one out to 60 inches, which should get you in the neighborhood of 24 gallons/side. You'll also need to extend the tank attach doubler forward of the spar. John can supply that too.
usmcshooter
Member
Lots of Help
Thanks for your replies everyone. I am working on an RV4 for later future use and living in SoCal with my dad in southern Washington, one of my plans is to use this little speedster to see him from time to time. The major drawback to the 4 is of course the fuel capacity. Well that and that tall people don't like the headroom but that doesn't apply to me now does it? Nineteen gallons per side seems almost perfect so now I think I will incorporate either the RV6 tank idea (more than likely) or possibly the HR idea since John is only a two hour flight across the Mojave and through Tehachapi. Thanks SR and LR, you two really contribute a lot. You two and Axel are my major sources of information on here.
Thanks for your replies everyone. I am working on an RV4 for later future use and living in SoCal with my dad in southern Washington, one of my plans is to use this little speedster to see him from time to time. The major drawback to the 4 is of course the fuel capacity. Well that and that tall people don't like the headroom but that doesn't apply to me now does it? Nineteen gallons per side seems almost perfect so now I think I will incorporate either the RV6 tank idea (more than likely) or possibly the HR idea since John is only a two hour flight across the Mojave and through Tehachapi. Thanks SR and LR, you two really contribute a lot. You two and Axel are my major sources of information on here.
Hey Guys! Been out of town for a few days. I have decided on putting the 6 tanks or the Rocket tanks to get the extra fuel I need. Thanks for the replies and info.. I will post more info when I talk to John!! Hopefully i can get hooked up with a set of rocket plans and 55gal tanks..
