HIlHas anyone had experience with this plane is a 70"span Beaver with floats.Is an older MAN plan.Bought the plane framed up but not finished just wonder how they fly will be used only on the floats.Funny the plan being old shows a 40 2 cycle looks awful small for a float plane this size?Thinking more like a 90 4 stroke!See much about Beavers but most are larger.Wings seem so long and thin compared to the fat fuselage!Thanks for any info!!

If it flew with a .40, and it's an old plan, it seems like you're just asking for complications. A K&B .40 made about 0.8 HP. Currently .40 size planes are frequently fitted with a .46, and they make almost twice as much power as the old K&B. I'd look at the new OS 4-stroke which is a .51 if memory serves. Put the .90 FS on there and you have an extra half-pound on the front, so you need an extra quarter-pound in the tail to balance it, and you sacrifice a lot of the performance advantage for a plane that now has to be landed fast because of the extra wing-loading. Fast landings can be a disadvantage for a floatplane since you have to clear the trees on the opposite bank then drop in and land before you run out of pond.

Beavers look sooooo cool making scale takeoffs, running about 300 feet then gently lifting off. I had a Senior Telemaster with 8-foot wings and a .91 OS FS. I bashed it a bit to look like a Beev. (See page 122 of the December RCReport)
It only weighed 10 pounds and it would make a scale-like take off from water at less than half-throttle. OR it would take off in 8 feet if I goosed it.

With a 70" wing you have a much smaller plane. I may just be old-school but I don't really expect Scale utility planes like CUbs and Beavers to do 3D maneuvers. You don't NEED a thrust-to weight ratio greater than 1:1.

I'd stick with the .91 FS....they only make the power of a good 60 two stroke anyway.
A 70" Beaver on floats is not a small plane....put some power in it. Position your radio
equiptment so that it balances properly without any any weight whatsoever.

FBD.

90 FS will be just right

40 will not get off the water.

65 might get off the water, with flaps engaged.

move battery, RX, servos to adjust CG.

Good Luck

I have that set of plans. The plane is mostly stick-built so it is very light for its size. I have a Unionville Beaver with a 72" span on floats that has the same type of construction. It weighs only 6 3/4 lbs with the floats and is overpowered with a Saito 56. A 91 would be overkill. A 46 two-stroke or a 52 to 62 four-stroke would be plenty. There are photos of it in this forum under the thread "seaplane photos" page 10.

Cheers!

Jollidude

I had one too, and it was powered with a ENYA 46 4-strk... Plenty of power (not if you want to do 3-D with it though) the original article the author used a Saito 52 for his and it was more than enough for floats...

That looks like a fun plane to build and fly, would anyone who built it recommend against it?

Thanks

jon