I have done a little research and have discovered that something called the Olmstead Propeller, an original high efficiency propeller was developed in the early 1900's, and used by the Navy, Glenn Curtiss and others. It reportedly far outperformed all the other propellers of the day. It was developed by Dr. Charles Olmstead.

Recently, I read an article in "Contact!" magazine about high efficiency propellers that have been recently used in racers. Lo and behold, the appearance of these propellers and the Olmstead propeller are very similar. The propeller is much wider closer to the the root and then tapers off to almost nothing at the tip.

Is there anyone who knows any more about these propellers and whatever became of them?