I recently mounted a set of Full Lotus Floats (with amphib gear) on my RANS S-7. These floats were previously installed on a different S-7 so it was an easy install. My question is, can I do a W&B by placing scales under the wheels? Basically placing a scale under each of the mains and under the nosewheels.

Simple answer is yes.

Another option is to compute the W&B rather then weighing the whole she-bang, Those floats most likely came with weighing as installed instructions and a document attesting to their installed weight and CG

I would get the W&B from the aircraft those floats came with to use as reference and calculate accordingly. Remember WxA=M

Just remember that computing an AC W&B is not on the list of pilot maintenance in part 43 for a reason so seek experienced assistance. And ya, I know your exp, common sense still applies.

So…

Get your leveling means from your TCDS

Drain fuel or fill tanks full and then subtract accordingly, often it’s just easier to fill tanks cause.

Plumb bob your datum and chalk lines on the floor to your wheel locations.

Be safe, rolling off a scale has damaged many a plane.

Using electric scales make sure they are hot and zeroed before you set the bird down or roll on and don’t wast any time, quick photos with your phone easy peasy.


Rocket

THAT is a sweet setup! I hope you come for a visit next summer. Water's getting a little cold now to wade out and help wrangle airplanes.

If your confident in the data, weights, moment arms etc. that you received with the float just do a paper amendment.

Is it just the photo, or are those floats set quite nose down reference the under side of the wing? Probably optical illusion.

I agree, get the data from the floats, and do the math.

MTV

[]

Zzz wrote:THAT is a sweet setup! I hope you come for a visit next summer. Water's getting a little cold now to wade out and help wrangle airplanes.

Too cold?

rocket wrote:[]

Zzz wrote:THAT is a sweet setup! I hope you come for a visit next summer. Water's getting a little cold now to wade out and help wrangle airplanes.

Too cold?

snow62Zfloats - 1.jpg

Nice! I remember those gigs.....Man, was I ever happy to come off floats in the fall.....

MTV

Thanks all!

In regards to paperwork...zilch....didn't get any kind of paperwork with the purchase other than a wiring diagram for the electric retract gear.

Mike, there is a 5 degree difference. I had called Harbor Sports Aviation in WI to ask them about installing these on my S7. They had done the original install on an S-7, the plane from which I purchased them off of. When speaking with the original installer, they said the floats are rigged to bolt up to any S-7 and that I should have a 5 degree angle. I'll take another photo of it when I get back to town that might show the angle differently.

I weighed it yesterday, WOW, what a porker now!! LOL 889lbs. if I did my math right. It was 661lbs.on tires.

Zzzzz, Definitely will get up for a visit!

WWhunter wrote:Thanks all!

In regards to paperwork...zilch....didn't get any kind of paperwork with the purchase other than a wiring diagram for the electric retract gear.

Mike, there is a 5 degree difference. I had called Harbor Sports Aviation in WI to ask them about installing these on my S7. They had done the original install on an S-7, the plane from which I purchased them off of. When speaking with the original installer, they said the floats are rigged to bolt up to any S-7 and that I should have a 5 degree angle. I'll take another photo of it when I get back to town that might show the angle differently.

I weighed it yesterday, WOW, what a porker now!! LOL 889lbs. if I did my math right. It was 661lbs.on tires.

Zzzzz, Definitely will get up for a visit!

Five degrees is reasonable. I suspect it was just camera angle.

Amphibs adding only 228 pounds (assuming I did that math right ) is REALLY light for amphibs.

MTV

rocket wrote:[]

Zzz wrote:THAT is a sweet setup! I hope you come for a visit next summer. Water's getting a little cold now to wade out and help wrangle airplanes.

Too cold?

snow62Zfloats - 1.jpg

But you're not IN THE WATER in shorts

Zane. Chest waders are your friend. I have them in my hatch all summer.

Rocket. You’re relying on the weight and balance provided with the airplane and with the floats, and with the rigging between the two being as specified. None of it certified. Put my vote in the column for the reweigh you’re proposing.

Are you looking for a procedure for weighing? For measuring? For calculating?

And, give us a report on how those floats perform once you get them in the water.

MTV

rocket wrote:Too cold?

BTW, nice plane Those dorsals are huge! I'm planning to add the sea fins to my horizontals.