170 float performance

[powderburner]

Just getting into the research phase of my life here and don't own a plane, i've road in plenty as a guide here in alaska, but never in a 170. i'm curious as to their performance on floats, i know alot of factors play in here, but just some personal experience on take off length, weights you've flown off water and so on would be a huge help.

Also what size bushwheels are guys droppin' on the 170 and getting for short field take off performance with a 145hp..?

[mit]

There is no Perfomace in a 170 with a 145 on floats!

[n2582d]

There is no Perfomace in a 170 with a 145 on floats!

Not when you're carrying three 200# hunters in parkas. But if you have one light passenger wearing as little as possible it floats quite well. Don't know how well it flys with floats though!

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[docfoley]

Nice!

[kbbell]

I've had my '52 170B with a STOL kit on floats since 1996. On Edo 2000s, the useful load is about 530 lbs; cruises at 95 with a 80x40 prop, 105+ with the 76x49. It's a 2-seater since the back seat is removed on floats. It's like an Aeronca Sedan, but with fowler flaps, no need to recover and quite a head-turner. I would have a higher useful load on wheels, but what fun is that?

[blueldr]

I can't think of any stock engined GA airplane that makes much of a float plane. Maybe a C-185 does OK, but I'll bet it wants a turbo too. The old Noorduyn Norseman did pretty good with a direct drive P&W 1340, but it would have been better with a geared 1340 and a bigger diameter three bladed prop like they put on the Otter.

[marathonrunner]

A DeHavilland DHC-2 Beaver stock is a very good performing float plane.

[kbbell]

It's relatively easy to come up with a useful seaplane if you're starting with 450 - 600 hp.
With the 80x40 prop on the 145hp, I can get out of some tight spots that my 235hp Maule STOL couldn't.
It's a great seaplane, but needs to be compared to a Stinson, Tripacer, PA-12, Aeronca Sedan or a Citabria and other like-powered two-seaters, not a C180. I love it and have for 16 years.

Bill Bellamy

[GAHorn]

It's relatively easy to come up with a useful seaplane if you're starting with 450 - 600 hp.
With the 80x40 prop on the 145hp, I can get out of some tight spots that my 235hp Maule STOL couldn't.
It's a great seaplane, but needs to be compared to a Stinson, Tripacer, PA-12, Aeronca Sedan or a Citabria and other like-powered two-seaters, not a C180. I love it and have for 16 years.

Bill Bellamy

Firstly, I have no real seaplane/floatplane experience. I once rode with George Courtney in his 170-B on Edo floats and original C-145 engine/prop. We had full fuel, two 220 lbs guys and about 30 lbs of junk and operated off a big lake (river acually, as it was lake Marble Falls and Lake Travis.)
I thought it was fun, but I didn't care for the "pendulum" effect of the floats. He later told me he was tempted to abort the takeoff as taking too much distance. (It was about a 1000' run on the water in my estimation.)
If I only flew large bodies of water with 2 people and didn't need to fly more than 2 or 3 hour trips, the 170 might be all I needed.
If I was an Alaska hunting/fishing guide tho', for just one client, I'd want a SuperCub. For more clients, a 185, or even better, a 206 on floats.
If money were no object it'd be a Beaver, Otter, or a Caravan.

[n2582d]

...If money were no object it'd be a Beaver, Otter, or a Caravan.

Or a Dornier Seastar ($6.2 million), Pilatus PC-6, Quest Kodiak, ICON, or AKOYA.

[kbbell]

We had full fuel, two 220 lbs guys and about 30 lbs of junk and operated off a big lake (river acually, as it was lake Marble Falls and Lake Travis.)
I thought it was fun, but I didn't care for the "pendulum" effect of the floats. He later told me he was tempted to abort the takeoff as taking too much distance.

It's not fair to judge a planes performance without doing a weight and balance, you were at least 150 lbs over-loaded. There is no pendulum effect with proper loading, only a smooth transition to the step. Fun plane.

[GAHorn]

...There is no pendulum effect with proper loading, only a smooth transition to the step. Fun plane.

You either misunderstood what I was saying...or the point is missed.
ALL floatplanes suffer"pendulum effect". Compared to their landplane counterparts
they have a large mass suspended beneath...and turns, and maneuvers must
deal with that huge"pendulum"suspended. It's an idiosyncracy of the type.
I believe we were at gross... not overweight.
I DO believe we were under floated.

[marathonrunner]

You are definitely under floated in a 170 with Edo 2000's. The pendulum effect is because someone did not do the proper testing for the certification or, those tests were not required when it was certified on the 2000's. With the Aerocet 2200's you are not under floated. You also are not going to feel the pendulum effect as the flight testing required it to show. a tendency to return to center when you had full aileron deflection and full opposite rudder and released the rudder and held the wings level with no opposite rudder being applied. This had to be done at forward and aft c.g. gross weight and light. I have gone up in other 170's with Edo 2000's and they continue to do sky brodies with no tendency to return to center. Hence the ventral fin needed.

I also have been in Beavers with the Kenmore finlets and same effect. The original ventral does allow them to return to center. With the engine mount extended on the Beaver it was even worse. Some of the undesirable seaplane tendencies are a result of the plane not being configured as tested and having modifications or STC's that affect the stability of the aircraft. That is why you are supposed to make sure that when you do install an STC you are not creating a potential problem from previous installations.

One good example of this and that I have discussed in length with an aeronautical engineer is when you have a STOL kit installed and then put on vortex generators. No flight testing was done in most cases to determine if one STC could have undesirable consequences with the other installed. It is however up to the IA signing off the STC to determine compatibility. How they can have more knowledge then the aeronautical engineers and structural engineers is beyond me...I surely do not.