Underwater Chainsaw

[MSU_Keith]

Came accross an ad for this - just wondering if anyone has ever used one.  It'd be great for cleaning up my pond.

http://www.csunitec.com/saws/airchain.html

I wonder if the 4hp rating is in air or underwater? ???

[BC_coops]

if it maybe runs quieter than a chainsaw motor ... thought it might make an interesting saw for a portable mill ...

until I looked at the power requirements : for a small 20" bar with 4bhp, requires air flow of 90cubic feet per minute at 90 psi.  On the compressor side, that would basically come out at 50 hp compressor ...

 ... 50 hp to run a 20" bar ...

not real efficient ... much more noise and smoke ...