Hi,

I've just started building a PICA T28 kit, and I'm horrified at how this kit is constructed. The wing ribs are "light ply" and the whole construction is incredibly heavy. Balsa spars, no webs, all the weight in the wrong places. The wing skins are 3/32 which I hink is too thick for a 60 size model. My 1/3 scale extra (GP) has only 1/16 skins for a 100" wing span.

I'm used to pattern planes and sport planes, this is my first scale effort.

Is this standard for all PICA kits? How do they fly being so heavy?

Why why why? I thought PICA had a good reputation.

STeve

Steve:

The balsa spars are just to hold the ribs in position while you skin the wings. The strength is in the sheeting, and it needs the strong ribs to hold its shape. It's an old Dave Platt trick, a lot of the planes he designed are made that way.

Don't be afraid of it, while it looks like it will be heavy you'll be surprised when you've finished it.

If you really want to, I suppose you could drop to 1/16" for the wing skins if you glass it, but I don't think it's either advisable or necessary.

Bill.

HI, im building a pica spit wing and i noticed the same thing, the wing is built like a tank. i guess its all in design though.

Yes, you can change to 1/16" sheeting but don't complain when someone (maybe you?) picks up the wing and puts their fingers through the sheeting!

I am assuming you are building the 1/5 scale model - right?

Jerry

im building the .60 size one, i dont know if you directed that towards me though

Okay, I guess I can buy the idea of a stressed skin construction. I am used to the idea of the spar being the load carrier, with ribs there just to give shape to a light covering.

Nevertheless, it does seem to be a heavier form of construction. I'm comparing this to something like the Great Planes Extra 330L, which had a proper I-beam spar, with light ribs, capped for strength. This wing would carry a much higher load, but weighs less per unit span than the PICA method.

How do these kits fly? Does anyone have other experiences with PICA kits?

STeve

steveg:

I am working on Duellists numbers four, five, and six at the moment. All have the same wing construction except #6. Never had a hint of structural failure on the first three.

Number six is a complete redesign for 15 size engines, and has an open bay wing.

The semi-monocoque is strong, and not as heavy as you think.

Bill.

I built the Cessna 182 1/5 scale and the wing is very heavy also but I bet I could walk across it if I wanted to.