Floats

[aero99]

Just curious what floats do to a planes performance.

Saw a Caravan on floats a few weekends back. Couldn't believe how large the floats were. I would imagine decreased weight and decreased speed due to extra drag.

 

[starchkr]

From what i understand floats actually increase gross and usefull load of an aircraft because they actually produce some lift.

As far as decreased speed, there is some decrease, as well as excess yaw produced by those float tips so far ahead of the CG and catching some of the air ahead of the nose.

There could be other things affected, but with my limited reading on float flying, this is all i understand. I am sure others will know much more than i do.

 

[aero99]

Didn't think about it like that. Guess it could have the same effect or close as tip tanks.


How hard is it to land a float on the surface with those tiny little wheels?

 

[cvsfly]

Floats generally decrease useful load and decrease speed. Haven't seen add on floats increase "lift". What they do increase is fun and function.

 

[A Squared]

cvsfly,


>>>>Floats generally decrease useful load

That is not a valid generalization. On some airplanes the installation of floats actually increases the useful load.

I'm looking at the weight and balance for my Cessna 180. On wheels the Max Gross Weight is 2550 lb. On EDO 2870 floats the Max Gross Weight is 2820 lb. Considering the weight of the landing gear and the floats, this results in a increase in the *useful* load of about 30 lb. This is not to say that all float installations will increase the gross weight, it depends on the specific airplane/float combination.

regards

 

[A Squared]

aero99,

to answer your original question, floats do just what they look like they'd do...add a lot of drag.

I figure that I lose about 20 kts in cruise, and a couple hundred fpm in climb. Power off glide starts to resemble a rock. It's an annual tradition with me...every fall when I come off floats, I badly overshoot the first landing on wheels. After a summer on floats, I just can't believe how far it glides on wheels.

regards

 

[aero99]

Thanks A squared.