I was wondering if anyone is aware of a chart that gives basic thrust to weight ratio needed to get the unlimited vertical seen in today's models. I understand that all planes are different and that because of that it is more difficult to pin point needed engine size. I am just interested to see where the cut off would be that would make the big difference between "it flies" to it's really fun to fly".

For example: Phoenix Models Extra 300S 46 ARF .46,57.4"

Wingspan: 57.4" (1460mm)
Weight: 3.52 lbs (1600g)
Length: 50.3 " (1280mm)
Airfoil: Fully-symmetrical, low-wing

I would imagine that the .46 will fly it, but what motor would really allow this plane to perfom?

(Side note, I have no interest in this plane in particular, I just grabbed it as an example.

A 2:1 thrust/weight ratio is what you want. There is a chart somewhere that compares the power loading (oz./cid engine) to performance. If I can remember correctly, something around 200 oz/cu.in. would be unlimited when correctly propped. If anyone has the Andy Lennon book R/C Model Aircraft Design I think the chart is in there.

Steve