View Full Version : Nov. 2009 Kitfox of the Month Paul Seehafer

11-01-2009, 10:58 AM
Paul Seehafer
Junction City, WI

Hi fellow Kitfox flyers,

Ten years ago I purchased my Kitfox Model IV-1200 as a flying airplane. To say it was a flying airplane is somewhat of an overstatement, it was in such serious need of attention that I decided I would buy it for the 912ul engine so I could repower my 2 stroke AVID FLYER, then sell the airframe. After unloading I realize my sad little Kitfox was really a diamond in the rough. It was loaded with lots of options like an IVO in-flight adjustable prop, a King KLX135 Com/GPS, King transponder, electronic fuel gauges, G-meter, big fuel tanks, cabin heat, speedster style wing tips, electric elevator trim, LP AERO tinted plexi windshield, turtle deck, bubble doors, speedster ribs in horizontal tail, Cleveland brakes, Whelen strobes, nav lights, carb heat & new style door latches. With all this it only weighed 627 lbs, which I thought was impressive. I decided to resurrect the sad little Kitfox much to the doubts of those around me.

Everyone seemed to think I was too busy to do another project having just completed a five year resto. of a Lake Amphibian. But I had a dream for my little Kitfox. I had decided early on it was going to be an amphib, replacing my straight float AVID FLYER that I keep on the beach at my lake home. Having an airplane at your house is the ultimate option. I toiled night after night in my workshop as the seasons came and went. Finally a bright yellow Kitfox emerged from its cocoon, and was mated to amphib floats. Most could hardly believe it was the same airplane I brought home years earlier.
On amphib floats empty weight came in at 776 lbs, probably heavier than it should be ( it took gallons of yellow aerothane to get coverage, even after painting the airplane white first). Even with the amphib floats and only 80 hp, it's a good performer. I had to replace the plus version IVO UL blades to a flatter twist UL IVO blade as I was unable to get more than 5100 rpm for takeoff. With the new blades I can get 5800 rpm which reduced my takeoff by more than fifty percent (two adults and 1/2 fuel previously took 30 seconds to liftoff, now it's 13). The IVO inflight prop is the biggest reason I haven't installed a 912S yet. I have some minor pushrod tube oil seepage on my 912. When I do that repair I may try a set of high compression pistons. An 80 hp 912 works fine for a Kitfox on floats but one can always use more power. If you don't have the option of using an inflight adjustable prop, or you just want max performance, you might consider a 912S or at least the piston kit in a 912.

My Kitfox never ceases to amaze me how well it flies. It is as nimble as any airplane I've ever flown. It is a joy to fly, and an airplane I will never get bored with. Play with the prop and throttle a bit and I can fly around comfortably at 75-80 mph in the low 4000 rpm range all day long burning 2.5 gallons an hour. I can pick it up to 100 mph and burn 3.1 gallons per hour. How many 80 hp amphibs can do that? If you really want to get somewhere fast, firewall the throttle and adjust the pitch to 5500 rpm. That will get you 125 mph which is nothing short of amazing for an 80 hp amphib. My normal cruise speed is in the 95-100 mph range. This engine and prop is really the ultimate combination. Once I did a test on a calm summer night solo and ten gallons of fuel to see how slow I could fly and still maintain control and altitude. After playing with the prop and power settings I was able to fly 63 mph at 3000 rpm using partial flaps. Back at the hangar I looked up my fuel burn and at that rpm it is about 1.1 g.p.h.
Talk about efficient. I don't use that throttle and prop setting but if I'm ever in a very low fuel situation I might use that to make it to my next fuel stop.

My Kitfox has very little dihedral in the wings. I never measured but I suspect the wing washout amount may have been slightly modified, as this is one Kitfox that drops a wing immediately when it stalls. The stall speed with full flaps is 36 mph power on, but when it stalls you can expect a sharp break followed by a spin entry. Rigging adjustments may improve this condition, but it doesn't bother me in the least as I like everything else about the way it flies and spin recovery is immediate. I never even fly close to those speed ranges. I have more trouble slowing down to under 70 mph. Liftoff on water is 40-42 mph, with speeds off pavement a bit faster (60ish) due to the negative angle of attack on the wings (notice the the nose low attitude with a negative AOA when sitting on the ramp). Landing approaches are flown at 70 mph with touch down on water around 45-50, and 55-60 on pavement. Climb out is best at 65-70 mph showing a 900-1000 fpm climb rate solo and full fuel. Drop the fuel and the temps a bit and the rate goes to 1100-1200 fpm. Add a passenger and I see 500-700 fpm.
FYI, Aerocet Floats began when Dan Denney asked Tom Hamilton (Glassair) to build a float for the Model 2. While the Aerocet 1100's that were designed for the Kitfox worked well on the early airplanes, they are pretty much at the end of their limits on even a lightweight IV but they do work. All told I heard there were less than 100 sets made, with most being amphibs, and the first 25 sets or so being straight floats. In spite of the shortcomings of the "Baby Aerocets" (as they are now so affectionately named), they are marvelous handling floats once on the step. I can lift one float out of the water and on one float do a 1500 ft diameter circular takeoff. I do have 23 years of float experience, but it is equally a tribute to the floats design, and to the nimbleness of the Kitfox. (Authors note: Do NOT try this at home)
Landing Aerocets at the airport can be described as "landing a shopping cart". The wheels are quite small and their is virtually no suspension. You have to be VERY gentle setting them down. The landing gear on any amphib float is not designed to be as durable as landing gear on a land plane. You just have to be gentle with them. The Aerocet 1100 floats being designed for early light Kitfoxes makes them marginal in buoyancy for even a lighter weight Model IV. In fact, the amphib Aerocet cannot be used with a Subaru powered model IV as their is not enough buoyancy to be safe. Even on a 912 powered IV you tend to get water coming over the bows when idling with two aboard. Will the airplane sink because of this? NO. But it is something you want to keep a close eye on in rough water. "The most dangerous seaplane is one that lacks the proper buoyancy, in the hands of a pilot that doesn't understand proper buoyancy". As I said earlier, once on the step they really handle well, giving water handling characteristics that are exceptional. I don't plan on replacing mine any time soon.

I've put almost 300 hours on my Kitfox IV amphib, and the more I fly it the more I like it. Actually, I am more and more amazed by it's performance and the fun it provides on the little bit of fuel it burns. A really nice feature of the 912 and the IVO prop is that it is the quietest seaplane you will ever hear. You don't have to worry about making your neighbors mad because of noise, a big problem with seaplanes in general. My amphib is so quiet that I have to be careful not to startle fisherman with my shadow when I come up behind them. They typically don't hear me until I am very close.

I'd love to have a 1400 gross weight rather than 1200. For most of my flying the 1200 is sufficient. While I love to take friends flying with me, I generally go out flying by myself, usually doing 30 or 40 water takeoffs and landings on different lakes here in Wisconsin on a single evening of flying. It's a great stress reliever.

I'd love for my floats to have a stronger landing gear so I could drop in on many of my friends who have grass strips. As it is I can still keep my Kitfox in the hangar and operate off of airports with paved runways, or very smooth grass strips. Since beefing up the gear will probably affect water performance, I'll keep things as they are. Water performance is more important to me.

I'm flying it so much that I'm not sure I will ever find the time to finish all the little details like cowl striping, instrument panel re-lettering, kick panel carpet, etc. I hate taking it out of service too long while I work on those finishing touches. But isn't it common knowledge that a homebuilt is never actually finished?

All in all, I couldn't be more pleased with my Kitfox. It most definitely ended up being the diamond I envisioned.
In fact it is such an impressive airplane that I have since purchased another 912 Kitfox IV that needs similar TLC. It's out in the garage waiting for me.

Paul Seehafer

11-01-2009, 11:01 AM
More photos from Paul.





11-01-2009, 04:29 PM
That is one sweet Kitfox you have there. Congratulations on a job well done.

11-01-2009, 08:17 PM
Nice Kitfox Paul. The photo of your Kitfox behind your house on the beach just speaks to me. Since '84' at Oshkosh I envisioned myself with a Kitfox on floats. Maybe someday. Save me a ride in yours would you. I'd even go on a diet to make it work. Maybe we'll see more postings on Kitfox float flying.
A new Kitfox amphib just flew for the first time here in Phoenix last week. Now if we could only locate some water for him.

11-04-2009, 04:24 PM
Some more photos of Paul Seehafer's Model 4 KOTM November 2009.:)




11-08-2009, 08:01 PM
Looking GOOD! It was good to see you out and about again this past summer.

11-19-2009, 07:52 PM
Thanks for the compliments guys.

Just like all of you, I have a blast with my Kitfox! Zero regrets!!!!


02-01-2010, 02:17 PM
Jim and Martine,

I measured my Kitfox today while it is on level ground in the hangar. It measures 114 inches tall, or 9 1/2 feet tall at the top of the vertical fin.

Oh yeah, my Fox has the 53" tall vertical fin and rudder should you need that information.