PDA

View Full Version : TAS with floats?



atc310r
08-13-2017, 04:26 PM
Just curious as to what people with floats installed typically see for air speed on their kitfox?

Obviously it will vary based on model and engine. But I am looking at building a SS7 with a 912is and doing amphib full lotus floats.

I went up in a Cessna 210 this weekend that had floats and it had about the same airspeed as a 172 which I found amazing! Very big, heavy floats on a plane like that obviously. Full lotus floats are light by comparison, but the frontal area and drag remain the same.

Thanks in advance guys!

av8rps
09-04-2017, 03:10 PM
Oops, just saw this post now and felt bad that no one had responded. So here goes:

Over the years we have found that Full Lotus floats in their non-amphib version are not any draggier than other floats on airframes like the Kitfox. That obviously changes if putting wheels on them as unlike other amphib floats, all of the gear mechanism and wheels hangs out in the breeze on the FL, causing mega drag.

So cutting to the chase, I would expect a Super Sport with a 912s Rotax and a Warp drive 3 blade prop to cruise right around 90 to 95 mph if on straight Full Lotus (at 5200-5300 rpm). I would expect the same speeds if going to another straight float, or even if it were an amphib float, with the exception of the FL amphib. I'd guess the wheels hanging out on the FL to be probably another 5 to 8 mph slower.

I based my opinion here on a variety of friends and airplane and engine and float combinations that I've helped with getting their Kitfoxes on floats, as well as my own experience with my 912ul Model 4 on amphib Aerocets.

Hopefully this may help to answer your question.

Paul Seehafer
Central Wisconsin

atc310r
09-04-2017, 04:29 PM
Thank you very much for the detailed response! I am pretty sure full lotus updated their amphib floats and made them like the zenair where the rear wheels are internal.

One other question for you, how bad are crosswind landings on the pavement or grass with floats? I imagine with all that surface area for the wind to grab only makes crosswind landings even worse on an already feather light plane lol just a sacrifice you make I figure

av8rps
09-04-2017, 09:03 PM
Yeah, I did see where Full Lotus redid their main gear layout, keeping the main wheels inside the float. But I also heard (through the rumor mill, so take that for what it's worth) that people are having performance issues with the new FL amphib. So make sure you find someone who can at least provide a good testimonial, if not a ride in theirs, before you place your order.

Crosswinds? Hmmmmm? Gotta think on that. About the only issue I've ever had is putting big side loads on the main gear mechanism when I got behind a gusty crosswind. Other than that, I guess I've been flying amphib floats for so long I don't even think or worry about it.

Oh, and for the record, these Kitfoxes can handle a lot of crosswinds. It's more about the pilot than it is the plane imho.