Racing propeller modified

It was fitted on 15 m and 37 year old pine that was used as part of celebration and decoration of a pine for 50th birthday which is fixed on ground. Rotation depends from wind direction as it is fixed on a pine. It will remain rotating on the elements for 50 days. Afterwards it will be removed and it's final use will be as decoration or to cool down in hot summer days.
You can see more pictures about this Slovenian custom on https://www.google.si/search?q=mlaj&newwindow=1&espv=2&biw=1680&bih=921&tbm=isch&tbo=u&source=univ&sa=X&ei=xW4cVZ6oO5ftaJTRgqAK&ved=0CB0QsAQ