Argess

1/ Does anyone know why installation instructions for "floats" typically tell you to install them with the "step" directly under the C of G? I sort of wanted to utilize the existing wheel mounts for the front of the float cage, but it puts the floats back a bit with respect to this requirement, although the tips are pretty well flush with the prop spinner, so it "appears" OK. Naturally, whatever I do, I will properly balance the aircraft for the correct C of G once the floats are installed.

2/ Also, I really didn't want to add a servo to one of the floats for the water rudder. The option in the instructions is to add another pushrod horn to the air rudder and use the supplied flexible pushrod between the air rudder horn and the water rudder arm. The floats I have are to be installed in a trainer that currently has a steerable nosewheel. Anyone see a problem with using a partial nosewheel rod (no wheel....just a control horn) to connect to the water rudder using the flexible pushrod?

Thank-you.

bkdavy

My Feedback: (1)

Normally, the step is located just behind (typically about 1/2" on a 40 size plane) the center of gravity. This is critical to ensure the plane has the ability to "rotate" on the floats. The take off process is to first get the plane "up on the step" Then the plane can rotate up and lift off. If the step is infront of the CG, the plane will not ride up on the step, and will instead ride on the back of the float. this will limit the rotation on take off.

There is a [link=http://www.rcuniverse.com/forum/forumid_176/tt.htm]Seaplane forum[/link]that has lots of good info.

Brad

khodges

My Feedback: (1)

To add to Brad's post, getting the plane up on step reduces the amount of float in the water, reducing drag and allowing the plane to accelerate to take-off speed. I've seen some models with the floats incorrectly set up that couldn't get off the water. Once they were properly set up, the plane flew fine..

If you want to make a linkage from the nose gear steering, that's fine, just make sure the water rudder goes the same way the air rudder does.

Argess

Thanks Guys....that explains a lot. And I never thought to look to see if there was a Seaplane forum. Guess I will have to check it out!!!

frugalflyer

"the tips are pretty well flush with the prop spinner"
The floats must extend ahead of the prop to prevent 'nose over'. For a 40 - 60 size plane 4", min is required

khodges

My Feedback: (1)

Here's a pic showing the step under the c/g, which is roughly where the struts attach to the fuse on this plane. Note how far ahead of the prop the floats extend (red line on float is even with the prop)

Argess

Nice pic.....between all of you, my questions have been answered. Thanks again everyone.