J3/90hp now on Floats- Weight and Balance anyone?

Hi all, finally have my J3 on floats, just wondering if anyone has a process or document for the final weight and balance. It falls within the proper range for C of G. I just have to get it all down on paper. Thanks once again.
Jeff

jwh said:

Hi all, finally have my J3 on floats, just wondering if anyone has a process or document for the final weight and balance. It falls within the proper range for C of G. I just have to get it all down on paper. Thanks once again.
Jeff

Click to expand...

What floats, and what specifically are you looking for?

MTV

Hi,
Just looking for a reference to a nice easy weight balance form for my J3 with edo 1400's. thx

They are all nice and easy. Do you have the weights and balance points of the airplane and the floats separately?

Look at the TC data sheet A-691 page 14, item 208 & 209:
http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/ec36f12e6e139c5b8625785c006c09c8/$FILE/A-691%20Rev%2034.pdf

Hi Bob, Yes i do have the weight and balance points for both. Just not sure on how to apply the weight and arm of the floats when there is no tailwheel weight..I know I'm missing something very obvious! Thxs sky wagon, I will look that up.

jwh,
The weight and arm of the floats, which is listed in the TC, is added to your original weight and balance. That number is the amount of increase in empty weight. The TC weight & arm numbers take into consideration the fact that you have removed the wheel landing gear.

That sure makes it easy. If you have any further problem, just post your current EW and ECG here, and we can show you.

Thanks to both of you for the info.
jeff

nope... unless you have a specific instruction like a Service letter or kit that says otherwise, the weight of the item is the weight of the item. the Spec lists weights. if in doubt, look at the weights of other like items in the Specification like propellers or tail wheels & see if that makes sense to you. and, you don't have any payload to spare anyway, the weight of the gear has to come off.... subtract the weight of the gear & add the weight of the floats. the wheel weights are in the Spec, but the gear legs and cabane, etc aren't listed, so you will need to weigh them. as for the weight of the floats listed in the Spec... that would be as they came from the factory, so any extra hatches, pump outs, or spray rails would not be accounted for. also prolly came with only one water rudder.... food for thought. you can consider the arm of the gear to be the same as the wheel. that and the arm of the floats are in the Spec.

because you have a nonstandard arrangement (C90) you will need to do fore and aft adverse load checks in your W&B as well as a basic.

Beezer, Congrats on getting your floats on. I also have a J-3 with 75hp, on a set of Baumann 1500s that was installed by factory. They did an impeccable job which came in at an even 900lbs. empty. I knew it would be heavy as I built it with extended baggage, fishing rod tube,etc., and would love to have a 90 but just make allowances on take-off conditions. Cruises at 80 on either wheels or floats. I can send you a copy of my weight and balance and you can adjust appropriately. It has a depiction of the plane on floats. I'll also forward a W/B in the ski configuration. Your going to have a blast.......in my opinion, the most rewarding flying there is.
Blue Skies(and always ripples on the water),
Denny

uuuhhhhh I have 2000s on my PA18A 160hp too