Bob Moore wrote:

Reed Judd-Dyer wrote

How does more blades equal less efficiency?

Those of us that flew rubber band powered contest model
aircraft way back ('40s-'50s) KNOW that the most efficient
propellor has only ONE blade...and a counterweight on the
other side. :-)

Bob Moore

A Helo with one blade would have to be the most uncomfortable ride,
until after a minute or so, when it had shook itself to pieces.

Jeremy Thomson