"G.R. Patterson III" wrote in message
...
Ok, I admit to not paying attention, but didn't some thread state that
thrust
and horsepower are equivalent? Or a 2/1 ratio? Something like that.

Nope. Or rather, if some thread did say that, it wasn't correct.

There's no single ratio to convert thrust to horsepower. You need to take
into account the aircraft's speed as well.

I have a 160 hp engine. I'd be moving backwards shortly after hitting the
trigger.

Well, regardless of the conversion, a 850 pound recoil thrust would
certainly hurt your airspeed. Hard to say exactly how much, since it would
depend on how long that 850 pounds of thrust was acting on the airframe.

Seems to me that there's a pretty good chance the force would just tear the
gun from the airframe, or break the airframe. Assuming a structure strong
enough to withstand it, you might find you can't take off with your 160hp
engine.

However you slice it, there's problems afoot with the plan.

Pete