FresnoR

FresnoR

Well Known Member
Has anyone ever heard of folding wingtips? Just the fiberglass portion.

With careful measuring, the RV-7 will fit in that extra space at the end of a row of T-Hangars, except for a few inches on each side of the wingspan. By being able to put them on a hinge of some sort, and leaving the spars in tact, I can slide it right into the tiny hangar.

This would bring hangar rent down from $295 to $30 per month. A huge savings in rent.

Anyone heard of this? think it is feasable?
 
I don't know about it from an engineering standpoint, but I really like the creativity of the idea.
 
FresnoR said:
Has anyone ever heard of folding wingtips? Just the fiberglass portion.

With careful measuring, the RV-7 will fit in that extra space at the end of a row of T-Hangars, except for a few inches on each side of the wingspan. By being able to put them on a hinge of some sort, and leaving the spars in tact, I can slide it right into the tiny hangar.

This would bring hangar rent down from $295 to $30 per month. A huge savings in rent.

Anyone heard of this? think it is feasable?
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More feasable would be choosing to own a 6A instead of a 7A. The 6A has a span about 2 feet less.
Also a small help would be to use teh horner style tips instead of the sheared tips. I think they are a couple inches narrower.
 
Make em easy to remove by using hinges like on the cowl....

Several guys have started using hinges to attach their wingtips. Makes em easy to pull and remove....
 
bhassel said:
Not bad :
+ $265 = - 2knts...
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Well, ...

I have to admit, if I could save $265/month by removing the wingtips, then I would remove the wingtips even if it costs two knots of speed.

But an alternate approach may be to install removable wingtips. That is what I plan on doing, and there is at least one company out there that sells a product for making the wingtips removable.
 
I sincerely hope that you will ALWAYS have 2 people there then pushing in and out. With this kind of clearance, you're just asking for a "dinged" wing.
 
Mel said:
I sincerely hope that you will ALWAYS have 2 people there then pushing in and out. With this kind of clearance, you're just asking for a "dinged" wing.
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I have that kind of clearance in my hangar (we keep two planes nose to nose in a T hangar). We solved the 'ding' problem by building small railroad tracks for sliding the plane in - the tracks guarantee we can't hit anything.
 
A track system was exactly what i was thinking to create the most foolproof system i can.

I like the idea of removable too, depending on how long it takes to remove of course. Anybody have any links to companies that offer those tips?

I may even mount rubber on the walls of any of the "danger" areas.
 
Flyguytki said:
What if you were to just eliminate the Tips all together and just cap the wing off.
-david
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Bob Axsom said:
I did that and the plane is about 2 kts slower.

Bob Axsom
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I did it, and gained a knot and a half (better use of Oswald Factor, Coriolis Effect, Bernoulis or .5mv(squared)...sumpin' like that, right Bob! ;)) More likely just dumb luck, to be honest! But stall speed went up 3-5 kts as well, so that's a factor to throw into the mix as you consider options.

Brian's idea on the hinge pins sounds neat (beats the gazillion screws), but it still might get old every time in and out!

Scott_F said:
If you do put folding wingtips on, you'll also need a Navy paint scheme and a faux tailhook.:D
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Now you're talking! Paint a superstructure on your hangar wall, with a logo above it that sez, "Where do we get such men?"

Fun ribbing aside, the concept actually sounds very cool, and if you could engineer it, very functional in a tight flight deck, er, I mean, hangar environment. Figuring out where to make the fold along the upper surface of the wing, given the curve, will be the tricky part.

Pretty innovative thinking...and yes, it would look very good in Navy Blue!!

Cheers,
Bob
 
ideas

The possibility of this sounds very interesting. If you have the creative mind that some builders posses, you could make a hinge for the top of the wing to tip joining area. All the other areas would be secured with sets of latches or pins for quick and easy folding of the tips. They could hinge upwards and rest on the top surface of the wings.
 
Another option to hinge pin removal method may be to use Mil Spec type quarter turn fasteners, this method would add an inch or so to each wing tip to mount the receptacles but the tip could be removed fairly quickly. The disadvantage is this option would be more costly then the hinge pin removal method.

Another thought would be to install two or three long fasteners on the centerline of the wingtip that would thread into nut-plates on the end wing rib. The wingtip location is secured by the tip "plugging" into the wing structure, the fasteners would insure the tips stay inserted into the wing structure. Alum tube could be used to to assist aligning the long fasteners (or long quarter turn) to the nut-plates. (or receptacles)

In all methods insure the tip is consistently located and does not allow contact with the ailerons.
 
How *deep* is the space?

If it's at least 26 feet, use the dolly/track idea & push it in sideways; no a/c mods required.
From Van's specs:
Span 25 ft 0in.
Length 20 ft 4 in.

Charlie
 
Get some wheel dollies and...

Based on the drawing on Van's website, the plane will actually fit in a box approximately 19.5 by 24.5 if put in diagonally. All you'd need is dollies for the mains. Ideally, these would be on tracks. It would be a little bit of trouble to build, but once done a whole lot better than r&r-ing the tips every flight.
 
Dimensions I am talking about.

Here are my two theoretical methods of fitting it within this hangar. It would be extremely tight and I would definitely lay down some sort of tracks to make sure it fits in there as smoothly as possible. Probably even mount rubber on the inside walls on questionable locations.

Now, I still need to finish building my airplane, and probably have 1.5 years to go, but when I see a possible opportunity to save some money, I jump after it.

The entrance to the hangar would be the bottom wall. I have very carefully measured it to the inch and it is perfectly to scale. As long as the measurements Van?s offers on its website are correct.

BTW, are the cowlings for the 320 and 360 the same length?

hangar%202.jpg


hangar%203.jpg
 
I would have to build some heavy duty full castering dollies that could slide under the gear, I would then bolt some guide rails to the floor of the hangar.

Attach a motorized tow bar to the proper place on the dollies, and I should be in business.

I know, its a lot of work, and is still only theoretical, but it beats sitting on the three year hangar wait list and saves a lot of money.
 
I assume that the inside of the 'L' is the adjacent hangar. How well do you know the tenant in that space, & how accommodating is the airport authority? You might be able to 'sublet' a foot or two in his space & build a box through the common wall. That would allow the plane (sideways orientation) to slide in another foot & clear the door. Failing that, could you do something similar to *your* door?
Just about anything to avoid repetitive changes to the plane, but for $200+ a month, I'd live with R&R on one wingtip, too.

Charlie
 
First off, if you can build an airplane you can certainly build a little dolly system, so forget any naysaying there. Regarding removable tips, I built mine with stainless torx screws. I'd say with a power driver they could be off in five minutes. I do think that over time the nutplates would wear. Hinge pins are a slick solution that should hold up well. Still, the preferred fix would be tobuold a small relief into the hangar wall. Or...you could build a folding H. Stab.
 
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