I recently built a Midwest 80" Extra 300S. 54cc conversion engine on the firewall. All up weight was over 17lbs when it was done.

At 6000' above sea level- there was NO way it would even approach a hover. I never flew it. Sold the plane on Ebay.

A close friend of mine told me to get the airframe as light as possible. This guy knows what he's talking about. He's designed several kits-- some of you are, no doubt, flying some of his planes. I won't drop his name, because it just seams tacky, but, suffice it to say- the guy knows airplane design. The suggestions he had were to scrap the sides and bottoms of the lite ply fuse. and use balsa longerons instead with balsa formers instead of the plywood formers.

It would have been a radical redesign of an old kit. But, looking back, it would have worked well. I just didn't have the confidence to take on such modifications to the kit.

I can only speculate at the weight savings; had I followed his advise. I'd bet it would have weighed somewhere in the 13-14 pound range.

It takes a 50cc engine to hover 15 pounds here at this altitude. Anyone who says otherwise has never tried it or is a flat out lier.

I have just recently completed the maiden flight on the World Models 300S with my 54cc engine up front. I haven't weighed it, but I suspect 16lbs or maybe a bit more. It won't hover.

Just to dispell any doubt, the 54cc conversion engine will turn a 22-8 prop at 6900RPM-- just as good as any DA or BME here. So, it's not that I'm low on power, the engines just loose so much at this altitude that it really takes a lot to hover and do 3D with any authority.

The ARF is just to heavy. I'd have been better off with the MW kit and modified it to lighten the airframe.