Bigger Tanks on RV-4??

[Mopar591]

I have searched and have not really found anything solid.. But my question is...
Has anyone put bigger tanks from a RV-6,7,or 8 onto a RV-4? Does anyone have any information on putting some sort of Aux. Fuel on the RV-4?

Thanks, Tyler

[RV Wannabe]

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

[pierre smith]

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,

[bkthomps]

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

[RV Jerry]

I have installed harmon rocket tanks (42 gal. ) on two rv-4s

[RV Wannabe]

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

[smokyray]

Originally Posted by Mopar591

I have searched and have not really found anything solid.. But my question is...
Has anyone put bigger tanks from a RV-6,7,or 8 onto a RV-4? Does anyone have any information on putting some sort of Aux. Fuel on the RV-4?

Thanks, Tyler

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!

[AX-O]

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.

[Mopar591]

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?

[F1Boss]

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