Model 5 Continental Performance

[Steve-TX]

Hi, Team Kitfox folks. Here’s my story: I wanted an affordable float plane and bought a Kitfox 5 (1550 gw) with a Continental 0-200 (experimental 110-115 hp) that came with Lotus 1450 amphibious floats. I’ve been flying it on wheels to get some tail-wheel time for over a year now and thinking it’s time to get the plane and myself ready for floats. I’m checking out schools for the rating and there are so many to choose from. The part I need advice for is the Lotus 1450 floats. I called a previous owner to learn what he learned and he basically said “forget it, it won’t work”. I was a bit in shock by this advice but nonetheless I was in the listening mode trying to learn from his experiences. He said the plane was too difficult to get off the water and considered it a failed project. He said he believed he hired the right people to rig the floats and that he had lots of float plane time. I think he was operating out of a near sea level location and not sure what the outside temp/humidity was. I didn’t ask him his weight but he mentioned something that made me think he was not that heavy. I’m close to 200 myself. The person I bought the floats from said he installed the floats but never water tested them. My plan is to remove the amphibious hardware and see if it will get off the water at a reduced weight. I can stay under mgw (1500 lb) limit with just myself on board. If that works out, I will be content and may decide later to add the amphibious gear back to the floats. I have heard lots of success stories of the Kitfox 4 on floats but my heavier 5 model seems to feel more like Cessna 150 performance. I rode in a KF 7 and it seemed to have better performance with the more common Rotax 912. I was recently flying with my son on a hot Texas day within 200 lb of mgw with all our gear and the lack of performance made me wonder how it would do with floats installed. Wondering if anyone knows of a success story concerning my plane and floats (or something similar) or has any advice to share before I begin this project. Thanks in advance. Steve J, Texas KF-5, Continental 0-200, Whirlwind 3-blade prop

[Esser]

I think if your model 5 has the same performance as a 150 you have an issue wih your plane somewhere.

[Steve-TX]

Possibility. I’ve wondered that myself. Compression checks were good recently. Cruises about 100 mph groundspeed with no wind. Prop pitch seems to give reasonable rpm on takeoff (around 2600) but is ground adjustable so I could try a different pitch. She’s just a dog when it’s hot.

[Av8r3400]

What does the plane weigh?

(I moved this conversation to it's own thread)

[Steve-TX]

W&B records show 858 lb. empty weight. Thanks.

[Esser]

Hmm for an o-200 powered plane that’s a decent empty weight. I don’t honk you’re making advertised HP or something...

[Steve-TX]

Good point. I’m not sure how to test that though. Please let me know any ideas to test that out. I’m not an A&P but I know some who are and perhaps I can bring it up at my next EAA meeting.

[Esser]

I’m not really sure either. My first guess would find a great running O200, put the prop on that engine and compare static rpm....

[Steve-TX]

Thanks, Josh. That seems do-able! I will start looking for an opportunity to do that.

In the back of my mind, I’m wondering if it may be an incorrect perception on my part. I used to fly fighters so perhaps my brain is comparing apples and oranges. However, I had a KF 7 instructor tell me the same thing (performance of a C-150) compared to his plane. And struggling to hold 5500’ altitude on a hot and humid Texas day (around 8500 density altitude) at about 1300 lb gw makes me just wonder.

Anyone know of any successful stories of KF 5 with 0-200 on Lotus floats? Or any KF 5 with any engine option on any floats for that matter.

[n85ae]

Paul Leidl in Minnesota has an IO-240B Series 5 on floats, haven't heard from
him in years on the forum, but if he's out there he would know. I like my
airplane with IO-240B and at light weight it is a rocket, BUT my impression is
the wing doesn't work well at heavy weight, and that sucks all the performance
out of the plane.

Here's my thoughts after 10+ years flying my Series 5 with an IO-240B, and
I do not have performance problems with mine. I can get close to 2000 fpm
on a good day solo, and I can hit VNE in level flight at full power.

Light weight with IO-240B I get very good performance, heavy, it's not as bad
as a C-150, but I would not call it good either. The original SkyStar sales video
where they say if "you ever wanted to fly the bush in a SuperCub, have we
got a plane for you ..." is a bit BS. Put a load in the plane and get near max
weight, it flies terrible. It is a truck with a heavy load.

I think the 912 weight engine probably works better in the air frame ... I
personally think it's the airfoil, and it works poorly at higher loadings. I'm
sure somebody will dispute this, but that's what I believe.

The other thing is the fuselage length is too short relative to the wingspan,
and it causes a lot of the constant annoying rudder pedaling you have to
do on a choppy day. I used to build and fly RC Sailplanes, and the Kitfox does
exactly the same thing, which in an RC Sailplane I would have fixed by
making it longer.

Next I would not put floats on my airplane with IO-240B since I know the
weight would kill it.

Jeff