Andy Dingley wrote in
:

I stumbled accross what appears to be a 3-blade microlite aircraft
propellor, and have ideas of using this in the construction of a
small wind turbine for charging a 12v battery.

Flog it on eBay, spend the income on a copy of Piggott's book

I was thinking about buying that book. I was hoping to avoid spending
actual cash on this experiment though!

Al