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I built this kit last spring (TopNotchKits.Com) and flew it from land without issues. Nice flying plane - but certainly not a trainer. However, when I put it on floats, it turned into an "evil" plane to fly! Very uncontrollable at slow speeds - landing was a huge issue! Takeoffs were not an issue but it was not fun at all in the air. I had a more experienced pilot fly it and he had same trouble I did.

However, after the trouble I had with my Hobbico Nexstar and the resolution, (detailed in this forum) I wonder if adding a subfin might be the answer to the problems. The floats are scale by the same supplier as the kit. They add 10 ozs to the plane bringing it to 50 ozs AUW with floats.

It flew so bad and I didn't want to damage the plane so I went back to the wheels and gave up on the floats. I would appreciate expert opinions as to if this might be worth another try on floats. I hate to risk the plane unless I have a good feeling the subfin will resolve the issues. I notice on the few Cessna 195s on floats photos that they have small fins on the horiz stab. I was thinking of a single fin below the tail section as it would be easier to attach.

Thoughts?

Thanks,
Joe

arobatx

The fins on the stabs do essentially the same thing a sub-fin does. On the full scale planes, I believe I read that a full-scale beaver pilot indicated that the larger single sub-fin was not used and the smaller stab fins were, because of clearance issues while turning the plane around manually at the dock...etc. I have flown a cub with and without the subfin, and I did notice a significant difference in stability. However I never enjoyed the look of it, and I liked the challenge of flying without them. It looks like a really nice plane, I would try it with the subfin and see what you think. If you are worried, get a more experienced float flier out to help you with the test flight and go from there.

Edit: also did you re-balance after installing the floats? A plane that is setup, balanced and flies nicely with wheels, often is more tailheavy with the installation of the floats and gear, so definitely check that out. If you are a novice float flier, I would definitely make the plane on floats setup slightly more noseheavy than with wheels, until you get used to the way the plane handles with them.

Chad

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Hi Chad,
Yes, I checked CG with the floats. Right on the money. Also tried a more nose heavy CG but same result. Went far enough once that it wouldn't ROW anymore. Incidence is 2.5 degs.

I would most likely get one of my more expert flying buddys to test fly. I fly a lot of float planes but I'm not in their league.

Thanks,
Joe

Wayne22

My Feedback: (2)

If the plane flies well on land it will fly well on floats...it is just a matter of setup....in fact they usually fly better on floats due to the pendulum effect the floats have on the lateral stabililty.

What does it do that makes it "evil"? Any specific behaviour that you can describe...

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Wayne22,
It has been 4 months since it has seen floats but as I remember, the slow speed stability was none existent. Very hard to fly it at any other than high speed. Wanted to climb initially but I could trim that out as long as I keep the speed up. At slow speeds it seemed like it was tail heavy and wanted to stall but CG was as it should be. I did try a more nose heavy CG. Maybe not enough but if I went any further, I will have to change the wing to float incidence so it will ROW.
Rudder and elevator were very sluggish at slow speeds.

Hard to remember exact issues at this time and I had given up on floats until I saw someone mention fins on a Beaver and remembered the issues I had with the Nexstar and they were solved by dihedral change and ventral fin. I have many other water planes so it wasn't a big deal but I really wanted it to be a float plane from day 1. I won't be able to do anything until spring now but though I would pose the issue here.

Thanks,
Joe

H5487

Joe,

I have a real Cessna 195 (actually, it's an LC-126 - the military version of the C195) but it's not on floats. However, I do know a little about the floated 195s.

First off, it is useless to compare a float plane to its land plane version (albeit not easy to do when you convert a landplane that you are already familiar with.) Floats add a LOT of drag and it takes a lot of horsepower to pull them through the air; usually using up most of the "excess horsepower" that the landplane version had. For this reason, float equipped C195s are slower and more sluggish than their wheeled cousins. And it would be logical to expect models of the 195 to behave similarily. So, when you converted your landplane 195 to floats, your first thoughts were undoubtedly "yuk!" Real C195s cruise at 160mph without floats but struggle to do 125 with them. Float flyers just accept that they're not going to get anywhere fast.

Secondly, floats add additional side profile ahead of the CG which decreases vertical fin/rudder effectiveness (decreases yaw stability.) This is why almost all float equipped planes have added fin area, usually in the form of a sub dorsal fin or stabilizer tip fins. (The real C195s used tip fins.)

But there are very few vintage planes that look as good on floats than a C195 and isn't THAT why you want to model one?

The two attached pictures are of the USAF Museum's LC-126. The first one was taken in Alaska, circa 1951, and the second was taken shortly after it emerged from the museum's restoration shop and hoisted to the museum's ceiling in 2001. Certaintly one of the USAF's "prettier" paint schemes isn't it?

Harvey

H5487

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Harvey,
Thanks for the reply. You are correct in saying a 195 is beautiful on floats. Without a doubt, my model is the nicest looking plane I have. I still love to look at the photos of my 195 on floats. I have several photos of float 195s from the Internet and they all have the tip fins.

I am tempted to give it another try next summer with some form of tip fins. I know my Nexstar flew 100% better once I added the subfin as did my Bonnie 20. The 195 just flew so bad with floats that I hated to risk the plane needlessly after all the effort to build it and it is a nice flyer on wheels.

Of course, it took me quite a lot of time to get used to the Bonnie 20 and get everything adjusted so it was a well behaved float plane. Love to do touch n' gos with it. And I think the 195 would be even more fun as it is a scale plane. Oh well, another season and we will see.

Thanks again,
Joe

H5487

Joe,

Please tell me about the Top Notch C195 kit. I bought a set of Gus Morphis's 1/5th scale C195 plans two years ago but have not yet started building it because of the apparent complexity. (Leading me to wonder if I would finish it. []) However, I looked up the Top Notch website as a result of your post and it looks like it's (comparatively) quicker and easier to build. Now that you've built one, what is your impression of the kit?

For some reason, the C195 has always been under-modeled. Very few kits exist and there aren't many plans available either. And I don't recall ever seeing a plastic kit (non-flying Monogram, Revell, etc) of one. That's too bad because it is arguably Cessna's prettiest design!

Harvey

Leo

It is hard to tell from the pictures, but the wing seem to have a low angle of attack in relation to the floats.
By increasing the AOA, the floats may be less draggy in the air
Just a thought

/Leo

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Harvey,
The plan for this kit was released as a free plan in one of the magazines - can't remember which. I was attracted by the beauty of the model but decided not to try to scratch build due to the amount and complexity of the parts to be cut out. I finally decided to get the kit about a year ago when another kit I was hoping to do was late getting here.

Unlike some kits today, John had this kit on hand for immediate shipment. I found the kit to be very complete with some unique methods of alignment for parts. Wood was good quality and I found only one piece warped. Keep in mind I am relatively new at this - I had built one kit - Aquastar - and scratch built a Drake II. So if I can do it, most can.

You get a full size plan to build on and typed instructions. You can download a file with some building hints & photos - nice. Certainly not for the absolute beginner! There are a LOT of parts in this kit - all laser cut. My notes say 110 parts in the tail group alone - all airfoiled vert & horiz stabs, etc.

This link gives a good idea of the construction. http://www.topnotchkits.com/index_fi..._sheet_WEB.pdf

I can say I am pleased with the results - at least on wheels! It is a beautiful plane in the air and even more so with floats. And, as you mention, not many 195s will be seen at the field, at least up here.

Hope you decide to build it.

Joe

H5487

Joe,

I got on the Top Notch website and saw the "Kit Highlights" page. I liked what I saw and ordered the kit about 15 minutes ago.

I didn't order the float kit.

Harvey

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That's great, Harvey.
Hope you keep us informed with your progress.

Joe

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Thanks,
Leo.

If I do put this back into the air on floats, I will keep your suggestions in mind.

Looking at some photos of full size 195s, they do look like there is more incidence.
Joe

Added a photo.............
Compared a full size to mine. Interesting!! Obviously, my comparison is not exact but does look like the issue Leo mentions.

H5487

I believe that the float-to-wing incidence relationship that you're talking about is to allow the wing to pitch up for taking off without having to rotate the plane until the float tails are submerged. I don't think that it is for in-flight drag reduction.

You mentioned that your landings and takeoffs were okay which led me to believe that the fuselage & wing-to-floats relationship was okay. But when you mentioned that the flight itself wasn't good, this led me to believe that you didn't have enough fin area to counteract the added float profile ahead of the CG. And, of course, the plane was doggier with the floats when compared to the wheels so its performance was drastically reduced.

Just my two cents - I know the principals of float flying but lack extensive experience!

Harvey

aeroscale

Here are another two C195's. The small one presented as a construction article in Flying Models. The large one (LC-126) I built from a German kit. I've got a Plans and Plastic package for the small one (57" span) and Hobby Hangar has a laser cut parts package.
AEROSCALE

H5487

HOLY COW, that's a nice LC-126!!! What's the WS, how much does it weigh, and what engine did you put in it?

Harvey

PeterC

I agree with what has been said about floats adding a lot of drag but there is one aircraft that I am aware of that actually improves it's performance with the addition of floats. It is the Polish Wilga. The Wilga is strictly a love it or hate it aircraft and I have not seen too many of them built except in magazine articles from Europe where they build them as glider tugs (R/C). It would definitely be an interesting float plane.
Peter

H5487

Pete,

I agree - the Wilga has a look that people either hate, or think is funky-cool. One of my friends had a real one back in the late 90s and it was....interesting! It wasn't on floats, though.

Harvey

EZRC

Joe:
I ran into the similar problems with another model on the same floats while developing the Bush Hawk XP model. This was before I designed the 195 kit. The Bush Hawk had additional scale fin area added but was still a hand full on floats so I tried something I had been contemplating for some time and it worked quite well. You may want to try it on the 195 as it flew quite well during the proto work with the same set up.
Since the 195 had such a long tail moment I didn’t think it would be as pronounced as you described. But here is what I did.
I added a vertical fin at the aft end of each float. I didn’t want to modify the model so that seemed the easiest fix. Since I used the floats on several different models that was a quick way to tame them all without changing the individual airframes.
I later used the same float set up on the 195 and it worked well. I must admit I never had the opportunity to fly the 195 without the added fin area. On the down side, it does put a ding in the scale look of the model.

I know it’s been a while since you posted this but I seldom get time to peruse these sites.

Hope this helps.

BTW
Your 195 looks terrific, you make me proud.

jv

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jv,
Thanks for the idea. Don't know if I will put it back on floats. It flys so well from land and I hate to risk it. I have 6 other waterplanes and another on the bench right now. It was very beautiful on floats!

You may be interested in the following video - with wheels - as it really shows what a nice flyer it is.

Thanks,

Joe
http://www.rcgroups.com/forums/showthread.php?t=784103