ceiling fans

Hi...

My wife wants to put a ceiling fan up in an area with a high ceiling.
What's the longest practical hang you can get with a ceiling fan?
Obviously, the shorter the hang is the more stable the fan is, but we've
got a long distance to cover. This is one of those 2-story openings
from the upper floor; would it be a good idea to install a brace at the
2nd floor opening?

As said earlier, the key is making sure the blades are balanced. And
purchase a nice quality fan.

Forget the fan, buy a tethered remote-control helicopter.

A lot depends on the specific fan and how stable and wobble-free it is on
its own. One of the most stable is the Hunter Original. The motor housing
is made of cast iron and the fan weighs in at nearly 50 pounds. It is
inherently wobble-free if the blades are properly balanced, and they
usually are.

In a previous house we had fans installed in a 2-story space. I mounted
them with the fan itself at 9-10 feet above the floor. Nary a problem.