[PCN]

I'am building a Carl Goldberg cub the full wing is 76.5" and the clipped wing is 67.5" I'am going to be using a 70 four stroke. When put on floats which would be the better wing ?

[Bill 6069]

If you plan on flying it off of floats. I would stick with the full span wing (76.5") Not only will it fly a little better it will have a more scale appearance. Clipped wing cubs are essentially never flown from floats.

[HAL9KPCM]

I would think you would want as much lift as possible to break the water tension and added weight of the floats, go full span.

[DO335]

Blah, blah, blah.

Speculation and guesses.

Speaking from experience, my choice would be to clip the wing.

You'll still have more than adequate wing, a floater - both on the wing and the water and a much more responsive, nimble plane.

Have had several clipped wings, in various sizes and flown a few full span as well, on water and land.

Clipped the wings on my Sr Telemaster same amount as on a Cub and put it onto floats as well. What an improvement with the shorter wing.

The big deal is to ensure that your float size is adequate in length and for your weight.

You'll also find that a clipped wing Cub flies very well inverted on floats - in fact my Sig 1/4 size did that better than upright. It also did fantastic multiple snap rolls, spins, split s, aileron rolls and scale like or rocket take offs as well.

If you never do any of that stuff and just stooge around, the full span wing will work fine.

Do you want a sports car or a loaded dump truck? The choice is yours.

[floyd]

I like clipped wings, they respond better to the controls and the planes fly better. You will get more lift with the full wing but I don't think a Cub really needs more lift. I taught a student on a 60 sized cub that had the full wing and I couldn't land the plane without killing the engine on approach. Even with the idle as low as I could get it. I told the student to build a clipped wing over the winter or he wouldn't be able to land the plane. Cheers Floyd

[PCN]

I don't understand why you couldn't land a full wing cub without killing the engine. A sig LT-40 witch is one of the best trainers around has a wingspand of 70" and a wing area of 900 sg inches.this should make it harder to land the the cub with a full wing of 76.5" and a total wing area of 744 sg inches

[machzx]

go clipped they fly awesome i had one with a 70 surpass II flew great
lots of lift and power
mine was coverd in 21 century fabric too so would be heavy by todays standard
floats are so light
just do a servo for watter rudders in floats easeir to change back and forth

[floyd]

Originally Posted by PCN

I don't understand why you couldn't land a full wing cub without killing the engine. A sig LT-40 witch is one of the best trainers around has a wingspand of 70" and a wing area of 900 sg inches.this should make it harder to land the the cub with a full wing of 76.5" and a total wing area of 744 sg inches

I've had several planes that could fly around at idle speed, and this Cub was one of them. If I had a wind I could land it but on a calm day it just wouldn't slow down enough. We didn't have a 500 foot runway or a 500 foot approach. I'm sure lots of RC pilots have had planes that just want to fly, not land. I had a Great Planes Revolver that needed a long approach on a calm day, it just didn't want to slow down and used the whole runway to land. Cheers Floyd

[OLD PRAIRIE RED NECK]

Originally Posted by DO335

Do you want a sports car or a loaded dump truck? The choice is yours.

I vote for the full wing and fly it like the "dump truck" it is intended to be.

Noting looks stupider in my opinion that a nice scale plane bouncing around the sky like a mosquito on steroids! And with floats on? Give me a break!

Or like a Cadillac on track day at the sports car club...

[Cougar429]

Back on topic, you have more than enough lift margin with even the clipped wing for floats, as long as you keep the weight down. Goldberg kits are very strong as is so real need for beefing up anywhere but at the rear float attach points, (if C/G has not already done that for you).

If you are building this from a kit you also have the option to mod the wing for flaps. That would make up for the loss of lift at slow speeds you would get with shorter span.

One thing to add is that C/G produced a set of "Super Floats" for this one in kit form which also includes a supplemental vertical stab for the back end to compensate for the aerodynamic differences with floats. Regardless of which floats you decide on, that extra fin is mandatory.

ps. If you build floats from a kit I strongly recommend mods so the servo is built in. Saves in scale appearance by not having what can otherwise be an obtrusive rudder linkage.