c-g problem
 

Hi folks,

I am just putting the finishing touches to a model, it is a Modeltech VASP, 60" span pattern ship. The c-g is indicated to be 7 inches back from the LE, but I am too nose heavy, must be the heavy MVVS 49 lump up front.

By moving the battery pack half way down the tail and adding 4oz of ballast at the tailwhell I can get it to balance, but this brings the auw to about 7lbs. The destructions don't give any idea of what the auw should be, so a quick wing loading calc gives a figure of 27oz/sqft. This is the first time I have done this calc and I have not included the wing area that is coverd by the fus.

I have no idea what sort of wing loading figures I should be looking at, other than as low as possible.

Ideas or advice,

Cheers,

Chris

c-g problem
 

Wing loadings can be deceptive. The only time you want a low wing loading is on a floater ie: glider or trainer.

I figure at that 27 ounces per SQ. FT. should be alright for a pattern plane. Just don't expect nice stall landings

c-g problem
 

Thanks for the reply, sounds like I should have the first few flights off the grass strip!

Cheers,

Chris

c-g problem
 

I've been out of the loop for a couple of months how did that first flight go

c-g problem
 

It went ok, I let one my preferred test pilots do the first run, the take off run was a bit longer than I'd expected, and once I got hold of the controls found it real nice and precise.

The only thing that caught me out was a slight snap to the slow/sharp turns, but apparantly this is to be expected for this type of model - pattern ship and high wing loading - and alas, my landing was a bit slow and it dropped the last foot and damaged the cowl, glad I was flying from the grass strip! Other than that, it handled really nice, and I expect to have a lot of fun with it. It wasn't blisteringly fast, but I expect that it'll get better as the engine gets more run in and I spend a bit more time tuning the pipe.

Since then I have not flown it, mainly been busy with other models, I have taken it to the field many times, but not quite felt ready to fly it solo again without my buddy pilot handy.

Thanks for the interest,

Chris