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bwilson4web
10-05-2011, 10:14 AM
Hi,

I'm looking at a Viking Dragonfly about 570 miles away from Huntsville so this weekend I'm going for a first look. There are many reasons why this deal may fall through. One critical aspect is I will be asking any foam-and-fiber glass builders in that area to see if they can verify the wings and canard have not had any separation of the fiberglass from the foam.

The plane is +20 years old and hasn't been certified since 1992-3. So I'll have to bring it back via ground and that is my question. Although the only gyro instrument is the turn-and-bank, my plan is: 1) remove all instruments and radio into a well padded box - they will be sent off for rework 2) remove prop and engine - the engine will be rebuilt and/or replaced 3) remove main wing - no big deal

The challenge is the conventional gear is mounted on the front canard so the fuselage will need a support to have the canard removed. So far, no big deal, I'll take measurements and fab a support, probably using the canard attachment points, and I'll be able to move all four pieces as needed: engine, wing, canard, and fuselage. Then I had this 'brain fart'.

My thought is to build a strong fuselage dolly with trailer wheels and bungie spring and trailing arms to the engine mount. Clamp the tail-wheel to a trailer hitch, add lights, and "hang" the wings in padded slings on both sides of the fuselage. Then trailer the airframe home with the engine, prop and papers in the car along with the box of instruments.

I have a licensed, folding trailer at the house and have no problem with painting the dolly frame 'red' and moving the license to the 'dolly/trailer'. Obviously, I've overlooked something but for the life of me, I can't figure out what.

When I get home, the airframe can be stored as one unit while I get the shop ready and start the project. My second choice is adopting a Jon boat trailer. Second hand, they are cheap enough and it wouldn't take much to make it work.

Thanks, Bob Wilson

ps. Photos of the plane: http://hiwaay.net/~bzwilson/dragonfly.html

Bill Greenwood
10-05-2011, 10:32 AM
I know almost nothing about that kind of plane; but I'd strongly advise caution, lest you buy someone else's mistakes and problems.
If the plane had small problems and could be flying as easily as the seller probably says, it would likely not be sitting idle.
If you can it is almost always better, evencheaper in the long run to buy a better plane, more real results than hopes and promises.

Bill Greenwood
10-05-2011, 01:18 PM
Bob, to continue what I was thinking ,you might try two approaches. The obvious one is the look at that plane and see what is done and what remains to be done to make it airworthy.

But consider another angle. Let's say it was a flying airplane ,average or above condition. What have you got then? I am not even a part of an expert on Dragonfly, but just looking at it one can see that it is an unusual design .The wing/cannard is behind the cockpit. Why, what are the advantages and disadvanteges? If this design was tried 20 years ago and is not prevealent today, why is that? One might surmise that it is likely that it has some flaw in the way it flies or some safety flaw.
I would guess that there are enough people around that built or flew them that you can get some info on them. Beware however ,cause you may get the Edsel effect, that is human nature that once you have bought or built something one is reluctant to say it is less than perfect.
Budd Davidson has a book about homebuilt designs , HOW DOES IT FLY. That might be worth checking, though I am not sure the Dragonfl is in there.
I know some homebuilts have trouble with slow flight ,and landings, maybe because they often don't have flaps. Also it has a very small tailwheel, how is the ground handling? We built at small homebuilt, a Starlite, and it flew well, but did not handle well on the ground at about 20 mph.

I may be all wrong on these points , and I know lots of guys like to take something and make it better through their own labor and ingenuity, but just know where the rattlesnakes are before you walk across the field. And I doubt if you would have to take the instruements out just to tow it home.

Good luck!

FlyingRon
10-05-2011, 01:37 PM
Cy Galley has certainly packed a number of planes into UHAUL trucks to get them back home from Oshkosh if they were too badly damaged to fly back.

I transported my Navion by getting a rack to hold the fuselage (it mounts where the wings attach) and putting the wings on saddles and just laying the horizontal stabs under neath and loading the whole thing up on a 24' flatbed trailer.

Frank Giger
10-05-2011, 09:05 PM
My thought is to build a strong fuselage dolly with trailer wheels and bungie spring and trailing arms to the engine mount. Clamp the tail-wheel to a trailer hitch, add lights, and "hang" the wings in padded slings on both sides of the fuselage. Then trailer the airframe home with the engine, prop and papers in the car along with the box of instruments.

Obviously, I've overlooked something but for the life of me, I can't figure out what.

Actually, it'll be cheaper, safer, and far less hassle to rent a flat trailer and put the fuselage on it.

What you're overlooking is the CG of the trailer. You want the wheels of the trailer to be behind the CG, but definately somewhere within the middle third of the trailer. In making the wheels of your cradle match the fuselage it might not be the best place for it, and you could wind up with a fishtailing mess behind you (or something that squeals wheels on every turn).

By putting the weight of the plane at the rear of the trailer, momentum is gonna make that sucker swing left and right and keep on going. Think arm and momentum, weight and balance. If the CG is too far aft the inherent instability does not allow for corrections. Ground looping a trailered plane would be the height of embarrassment.

bwilson4web
10-06-2011, 12:44 AM
. . .
What you're overlooking is the CG of the trailer. You want the wheels of the trailer to be behind the CG, but definately somewhere within the middle third of the trailer. In making the wheels of your cradle match the fuselage it might not be the best place for it, and you could wind up with a fishtailing mess behind you (or something that squeals wheels on every turn).

By putting the weight of the plane at the rear of the trailer, momentum is gonna make that sucker swing left and right and keep on going. Think arm and momentum, weight and balance. If the CG is too far aft the inherent instability does not allow for corrections. Ground looping a trailered plane would be the height of embarrassment.
Thank you!

I knew I was forgetting something and this makes a lot of sense. With the engine, wing and canard off, the CG is going to shift significantly towards the tail. Worse, if there are any wheel alignment issues, I could easily see coupling causing an unstable tow. Furthermore, one should not do a solo cross-country on the first tow.

Renting a trailer makes a lot of sense so I'll just have to check prices. Now if I can borrow a horse trailer . . . I'll still need the dolly to mount the fuselage.

Thanks,
Bob Wilson