Posted by Bob Brock on Friday, November 6, 2009 @ 05:47 PM:
I noticed that C. Weber's RF-4 has at least one tank in the wing... seems to be forward of the spar... does any one have any information regarding such a tank, e.g., size, wt., mounting, material, plumbing, etc. I do have an extra 2.7 gal. behind the seat in a neat aluminum tank... can take it out and go to the pumps. It works great and fills into the main tank at the cap... simple and somewhat fail safe.
Anyway, thought it might be good to consider another 3-5 gal for long distance legs... any ideas??
Posted by jb92563 on Friday, November 6, 2009 @ 06:52 PM:
Do you have an electric in flight fuel transfer pump or is it a ground only filling operation with your seat back tank?
--------------------
Ray
RF4D #4057 N-1771 Rectimo 1400cc
http://picasaweb.google.com/jb92563/FournierRF4D
http://www.touringmotorgliders.org
Posted by Collin on Friday, November 6, 2009 @ 08:04 PM:
Charlie's are 3 gallons each. Uses a ele. pump to pump in main tank.
Posted by Bob Brock on Sunday, November 8, 2009 @ 01:25 AM:
I do have an electric fuel pump for in flight operation... basically I fly for an hour and a half or so, then transfer the 2.7 gal. into the main tank. The fuel runs in a clear line from the back tank and into the main tank via the fuel cap... it takes about 5 min for the 2.7 gal. transfer. I do this at the front end of the flight to make sure it works and I will have access to the entire fuel supply, i.e., 12.7 gal.
My RF-4 has a generator that puts out about 1 amp., and that keeps the battery charged.
Posted by Bob Grimstead on Friday, November 13, 2009 @ 08:24 AM:
Are you guys aware that there are original Fournier drawings for a gravity-feed fuel tank in the luggage locker?
I only became aware of this a couple of weeks ago.
Gravity feed is so much simpler, more reliable and safer than pumped feed, don't you think?
Yours, Bob
Posted by Bob Brock on Friday, November 13, 2009 @ 12:56 PM:
No I didn't know that... I would be interested to see any information.
The portable 2.7 gal. tank in N 7725 is rather neat and works fine. It can be removed when not needed, and even taken to a gas station for a fill.
The extra fuel tank came with the aircraft so I really did not give any other application much thought. It was there so I used it!
Now that I am rebuilding the aircraft and wings, I want to upgrade while still keeping true to the wonderful design by Rene.
Perhaps that is the big question about modifications, i.e., "Is a change an improvement based on newer technology--- something Rene might have even used if it were available in the 1960's??" or do we stick with 1960 products and that expertise?
I visited the Windward-performance people in Bend, Oregon.. they build super light carbon fiber aircraft (SparrowHawk, et.al.) .. and wonder if the RF were designed today they might be carbon fiber??
My goal is to keep the RF-4 an RF-4.... but upgrade it with new wires, instruments, radio, fabric, paint, prop and rebuild the engine but keep it on the same mounts, etc. I believe using fiberglass on the fuselage is an upgrade over cotton but I can understand some owners might want to keep it as it was in the 1960's. When I get to the wings, I plan to replace with the Poly Fiber system. .. thus having what I believe to be the best fabric choice for each surface, especially for the wet Pacific Northwest. Additionally, I want to take advantage of the knowledge of people who know so much more than me. I appreciated the healthy discussion of choices.. and the ability to weight out the advantages and disadvantages of each choice. Thanks...
Posted by Bob Grimstead on Thursday, November 19, 2009 @ 10:46 AM:
Hi again Bob,
I would definitely re-cover with Polyfiber. I have two RF4s, and the fabric and paint on the Polyfiber-covered one have weathered and lasted much better than the Ceconite on the other one. Also the Poly-Fiber is much more flexible and flame-retardant. We recently tried lighting a bit of painted fabric from WGN's old rudder covering (original). It went up like a bomb in my hand and I had to drop it quick!
I have just had my Maule re-covered in Polyfiber for the same reason, and would never consider anything else in the future. It is twice as expensive, but ten times as good, and therefore much better value.
I would personally re-cover my fuselages in Polyfiber too. I do not like the idea of a stiffer, possibly heavier fibreglass covering that will stick forever.
Yours, Bob
Posted by Bob Grimstead on Thursday, November 19, 2009 @ 10:51 AM:
As regards your leading-edge fuel tank.
At Gap-Tallard Rene said he was horrified at the American-designed leading-edge tank modification to Mira's RF4 when he arrived at Dahlemer-Binz after his west-to-east Atlantic crossing, because it had seriously compromised the wing's structural strength.
If I were you, I would check with Rene, or original drawings, or with Mira, to ensure your tank installation is safe and sensible.
Yours, Bob
Posted by Bob Brock on Thursday, November 19, 2009 @ 05:35 PM:
Talk about timing... the mail just came and Mira sent me drawings of his ax. wing tanks along with a copy of page 195 from Rene Fournie's book where he talks about Mira Slovak landing at the International Airshow at Le Bourget in June 1969 after crossing the Atlantic with only 2 stops and receiving the award for the most difficult journey. Rene also discussed the wing structure of Mira's record making RF-4. I am confident fuel tanks can be added in a way that would not compromise strength or safety.
I don't know if I will build a wing tank... just getting all the ducks in a row... I believe Mira had about 30 gal. total... and I would have far less... perhaps just a 3 gal. wing tank like C. Webber's aircraft (which is for sale and now at a much better price).
Thanks,
Posted by Bob Grimstead on Friday, November 20, 2009 @ 08:21 AM:
Hi Bob,
Here's the GA drawing of the only approved aux fuel tank I know of.
I would much prefer to use this, or a variation on this (as Matthew and I shall be doing next year) than cut into the wing structure in any way.
Yours, Bob
Posted by Mira Slovak on Monday, November 23, 2009 @ 00:26 AM:
Here is some information for those who might be interested about the wing fuel tanks on N-1700.
The first 1700 fuel tanks have beem installed by Sportavia Co. at Dahlemer Binz. My first contact was with Mr. Kupper, director who supervised the production of RF aicraft at the factory.
40.1 liters tank was installed in each wing. Fuel lines with open-closed valves connected to manifold feeding to electric Bendix /Mickey Mouse/ fuel pump and line to the top of the main fuel tank. When the windshield was covered with benzin...main tank was full. This instalation worked perfectly. Unfortunately according to Mr. Kupper Jr. there isn't any kind of documents about this installation. I have original documents signed by Mr. Kupper Sr. that Sportavia Co. installed 2x 40.1 lit. on customers request and that is all. Then nice crash in Santa Paula airport, they call it pilot error, which has nothing to do with the wing fuel tanks.
The fuel tanks of second 1700 is a different story :
Posted by Mira Slovak on Monday, November 23, 2009 @ 01:10 AM:
The installation of the fuel tanks was a labor of love by three old timers, friends of mine at Santa Paula airport Ca. No American engineering whats so ever. Cutting into the structure of the wing, /I think...probably/ was done on the old timers principle that flying wires are holding the main and second spars, so no problem to replace the leading edge with new fuel tanks. /RF-4... no flying wires.../ I wanted more fuel, so they gave me 18 gal. on each side, thence only two stops crossing the Atlantic. The RF-4 1700 managed a "milking climb"/ 200 ft. up then 150ft. down, later 200 ft. up and 200 ft.down and so on/ over Greenland's ice cap at Fl. 11.500 and then, 1700 flew quite comfortably. The rest is an other story...
Rene's inspection of second 1700 at Le Bourget Air Show almost gave him a heart attack. He didn't know that his design can fly with part of the wing missing!!! Magnificent design and the designer.
And that is the story, please do not copy our Santa Paula BIG mistake. Listen to Rene.
Fly safe. Mira Slovak.
Posted by Mira Slovak on Friday, November 27, 2009 @ 11:21 PM:
And now when we are on additional fuel tank subject. Let me present my personal objection for having fuel tank in baggage compartment.. With all respect to Capt. Bob, here is the reason and the scenario... 1968 on my arrival at Santa Paula airport, or 20 feet short of the 04 runway in the 10 foot ditch, on the sudden stopage, somethng hit me in back of my head which resulted damaging my 6 nerve and I have experienced double vision for next six months. Fortunately, I have shiped my HF radio and the two man raft which were located at baggage department, via mail from east coast. If I had the equipment with me... it would be as 20 lbs."plus" horizontal French Guillotine chopping my head off.
Only one satisfaction would be...French airplane... French Guillotine.
Think twice before you install any country's type Guillotine behind your head, which would be same as a English Bunt... I call it: one half outside loop from horizontal flight performed with RF-4 on end of air show sequence....same result.
Of course if you have guarantee that you will not bent your RF-4, then fuel tank in baggage compartment is perfect place to have it. Enough said.
Fly safe.
Mira Slovak.
P.S.
Cutting into wing structure to accommodate fuel tanks is : beside lowering wing structure integrity, quite a complicated...lots of hard work job, where a wood expert is a must, ala Sportavia Factory 1968. Definitely NOT as we have done at Santa Paula 1969.
Just a thought. M.
Posted by Bob Grimstead on Saturday, December 12, 2009 @ 09:00 AM:
Thanks for that Mira,
We have been working on installing a temporary flexible rubber tank in the luggage compartment.
They are available in America, although they come from Australia, of all places!
The company's called something llike Fluid Containment or something. I'll look it up.
We have a ten litre one at present, to give an hour more endurance, but they come in many sizes. We'll let you know how we get on.
I figure a rubber bag full of fuel should just bounce off my bony head when I crash!
Yours, Bob
[Edit by Bob Grimstead on Monday, December 14, 2009 @ 12:34 PM]
Posted by Bob Grimstead on Monday, December 14, 2009 @ 12:37 PM:
it's Liquid Containment
http://liquidcontainment.com.au/fuel_bladders.html
Yours, Bob
Posted by Bob Grimstead on Monday, December 21, 2009 @ 09:26 AM:
and you are all probably aware that Sabine and a few other European Fournier owners have neat aluminium tanks behind their seats, where they are securely held in place, although they do need fuel pumps to get the fuel up from that low position (electric ones presumably, although that's another thing to go wrong plus another source of sparks).
Yours, Bob
