Floats

[Breathless]

Hello,
I'm looking for some input on floats.
Will be installing on my Kf 4 / 1050 gross Wt. Rotax 532.
Realy like the aerocet but a little on the heavy side. The inflatables appear to be dirty getting off the water.

[Ron S]

Hi Jim,
I bought my Kitfox 4-1200 from a friend who had it on Full Lotus floats. Although I myself never flew it on Full Lotus I was aware of the advantages and disadvantages. On the plus side there was enough flotation. He even flew it off of snow. What he did not like was the tendency to porpoise on takeoff and the trouble of purging condensation in the bladder.
I did not buy the Full Lotus wanting to have amphibs in order to hangar the plane. I ended up with Aerocet amphibs. They have barely enough flotation for my plane but should be fine for a 1050 Kitfox.
If I had to do it again I would look into Zenair floats. I had them on a Challenger before and they were great but were not available when I was looking for floats for the Kitfox.

Ron
Kitfox 4-1200, 912S

[av8rps]

Jim,

I did the test flying for a friends' Kitfox IV-1050, Rotax 582 warp drive prop on full lotus floats (non amphib version). I had no experience with Lotus previously and had only heard bad things about them. But after putting hours on his plane, I was actually pretty impressed with them. I also had the opportunity to experience them in the snow, and they were great there too. Anyhow, the IV-150 with the 582 on those floats made a nice seaplane. The only thing I would say I didn't like about the lotus is that they aren't good in rough water (but these little planes shouldn't be out in rough water anyhow), the amphib gear for them at that time was a joke (heard better now?), and I kind of like storage compartments on floats. But other than that they worked very well and provided plenty of floatation (his were 1260's). In fact, we learned later when a RANS S-7 buddy changed over his Lotus to Aerocet straight floats because he didn't like how draggy they were that they weren't as draggy as he thought, as he gained a whole 2 mph with the Aerocets. So removing the draggiest floats ever made (we thought) and replacing them with the cleanest aerodynamic floats only gained him that little difference says either the Lotus aren't as draggy as they look, or the speeds we fly our little planes at doesn't pay much attention to drag, or both. All that said, I learned first hand that full lotus floats are a better float than I ever expected them to be. And the fact that you can bang into docks or rocks with them and not worry, or use them as snow skis is just icing on the cake. I'd recommend them.

There's my experience with Lotus floats on a 582 airplane.

Paul S
Wisconsin
Mod 4-1200 912ul aerocet amphib

[Breathless]

Still gathering input. All Mfg. have +/_ 's. Some say to go up one size for Full-lotus for more flotation. But to me it seems that their would be just more weight. Allso thay would trap even more water between the forword tubes and abrasion boot, adding to takeoff run.
Re: Condensation, I would use nitrogen to fill chambers.

I would like to compair performance spec's pre/post float intall.
Haven't been able to find much on install kits or do's, don'ts other than Full-lotus web site.

Thanks to all for your help.

Jim

Kitfox 4
Mfg 06/01/1993
Rotax 582
Ivo IFA prop
Empty Wt. 520 Lbs
Top speed 117 Mph.
Cruse 105 Mph.

[jsimmo97]

Still gathering input. All Mfg. have +/_ 's.

where did you end up on your float research for your Kitfox?

[kodi]

Hi All: I have a KF 111 (582) on Puddle Jumper amphibs. Have installed a linear actuator system for for activating the retracts and a celenoid for locking the gear down. Works great. But were I to do it again I would put a set of Czech floats with manual hydrolic system on it. One on my friends here has a Model 4 with 912s and Czech floats. Gets an honest 110mph cruise and is off the water in 8 seconds. To my mind this is the best combo on can get for the Kitfox.
Don

[ahoadley]

Hi,

I have been flying my Kitfox IV on Full Lotus 1260 floats, using the Skystar mounting kit, for several years but they are showing wear and I am looking to replace them. Several years ago I bought a new set of Lotus 1260 floats, but they worked very poorly, and after spending a summer and a half with problems, I returned to my original floats. Given that the "new" Lotus floats don't work on my airplane, I need to look at composite or aluminum floats. The Zenair (formerly Czech) Floats look like a good option. I would very much appreciate any experiences you could share and if possible photos of mounting system, step/cg locates, relative angles, etc. Art

[Newkid]

Just out of curiosity, what was different between the old and new Lotus floats?

[ahoadley]

The difference that I believe caused my problems was the replacing the wooden stiffener plate between the hull cap and the bottom of the float with an aluminum one, plus adding to the thickness of the hull cap itself. These together made the bottom of the float, forward of the step, very flat. My original floats have a concaved shape forward of the step. This gives more hydrodynamic lift, which lifts the float higher out of the water. When I examined video of both floats during takeoff, the new design stayed deeper in the water and produced considerably more spray. The takeoff time with one person is about 13 sec. on the current floats and was about 36 sec. on the redesigned ones. This is after I installed a Full Lotus kit that increases the step height by pushing the step down, using two 15psi airbags located just forward of the step, on each float. My current setup using the original floats does not need these. Before increasing the step height, I never got on the step where you could find the sweet spot, it had none. Another change was the increase in the bladder thickness. This was a good idea and I kept them in my current setup. I no longer have any air leaks. I have photos in my album showing a float comparison. I also found that the fabric tubes around the aluminum tubes were loose and the floats moved aft with each landing. The deck shown in the picture was designed to clamp the float in position and I have kept the deck on my current setup because it keeps me from stepping on the air valve. I do not know if Full Lotus has fixed these problems or not. They did return my money, but I lost one and a half summers trying to work out the problems, and on one occation almost lost the airplane.

Art

[Av8r3400]

Reach out to Av8rPS (http://www.teamkitfox.com/Forums/member.php?u=881) on this board. Paul (http://www.teamkitfox.com/Forums/showthread.php?t=931) has a Kitfox IV on Aerocet floats and is quite an expert on amphibs.

[ahoadley]

I am in the process of designing and building the attachment hardware for my Kitfox IV for Zenair (use to be Czech) 1450 floats. I have my floats attached to each other with the spreader bars. This involved machining a 7075 aluminum fitting to attach the spreader bar streamlined shape to the round float attachment tube. I have designed the location and angle of the floats and built a jig to represent the aircraft attachments (my kitfox is at the lake on Lotus 1200 floats). Now I am getting the angles and length for my struts and cross cables. I have the attachment fittings designed but have not started the machining project. Of course, non of this has been tested in operation. I hope to have that completed later this summer. I can send you pictures of what I have if you wish to send me your email address.

[pt17]

I am installing zenair floats to a Highlander and am also trying to sort out how to attach them. I believe the fittings are very similar to the Kitfox IV which has lead me here. Have messaged ahoadley and av8rps, but maybe it's holiday time in USA. Can anyone else help. Thanks Pete, Melbourne Australia.

[Dave F]

Jim,
You must have the fastest Kitfox 4 on the planet with those posted speeds.

On floats you will be around 80 to 85 mph in my opinion.

Your plane a 520lbs will benefit you once you get floats going.
I have seen Iv at 850 lbs !! YIKES on wheels double YIKES !!

you will gain 150 to 200 lbs with amphib floats.

Good luck , was on lake with mine last few days -- off to another lake soon today.