Would like Info On IFA IVOPROP

[SkyPirate]

Back in the 1900's ,..thinking 97,..might be off a year or so ,. I was playing with a set of flat bottom fiberglass floats,..that were rated for around 700 lbs ,.so I put them onto a 3/4 wing sprint,.. top speed prior to putting the floats on was 65 mph,.after I put the floats on my speed indicated 70 mph,..this is with a 447 fix pitch,.
the floats,..I cant remember the manufacturer ,..were round top flat bottom with a 2 1/2 " step,..the had a single top square tube mounting system that was mounted on top of the float from the step forward about 5',..I didnt like the way the floats,.."flopped" and twisted when taking off and landing so I added some braces on a 45 degree to the inside ,..or between each float,..so ,..my point ,.I had added even more to the drag of the orginal set up.
I didnt get too indept as to finding out why I gained speed with the floats,..I'm sure the added weight ,..but also the angle of the bottom of the floats in relation to flight had something to do with it,..

So ,..the shape of a set of floats? the angle of incedence in relation to flight? and the weight? and of course the drag of the system you choose to mount the floats,..evidently I got lucky in my set up because I was able to gain speed even though the drag was increased.
the flat bottom floats flew great ,..the problems with them ..flat water ,..you had to basically go out to where you wanted to seperate from the water and spin around a couple times,..back track down wind and then head towards the waves you had made to get seperation,..
and I did not land or take off in any swells over a foot,..the flat bottom floats will literally beat the crap out of you at speed
I would NOT recommend flat bottom floats for a kitfox or anything that hit's or leaves the water in excess of 40 mph

sorry for getting way off topic ,..just a little piece of float info

[av8rps]

Back in the 1900's ,..thinking 97,..might be off a year or so ,. I was playing with a set of flat bottom fiberglass floats,..that were rated for around 700 lbs ,.so I put them onto a 3/4 wing sprint,.. top speed prior to putting the floats on was 65 mph,.after I put the floats on my speed indicated 70 mph,..snip snip

Interesting information for sure. It is basically unheard of for any airplane to gain speed by adding floats. Traditionally the best you can hope for is to not lose any speed, but that is also rare. Early, very lightweight Avid Flyers were known for not losing speed with the addition of floats. But as the Avid Flyer's evolved, and got heavier, they too lost speed.

And I couldn't agree more with your comment about flat bottoms on floats. I also own a LA-4 Lake Amphibian, and it has a pretty flat hull compared to the later "Renegade" model. And let me tell you, rough water and boat wakes can be a real handful. There's nothing worse than not being up to flying speed and getting tossed into the air when you are in an airplane that can quickly develop an uncontrollable porposing condition. The deeper V they put on later Lakes solved that problem 99%. So even if a flying boat vs a float, flat bottoms are not the answer.