So, I came across this propeller with tip fins on ebay. Seemed kinda strange. The ad said to look up "increasing propeller efficiency with tip fins". Made me wonder if it actually works and, if so, why ACME wouldn't already be doing this. Anybody seen this? Is it just a gimmick? Or is the difference so slight that it is just not worth the cost to produce? If someone posted this on April 1 I would be laughing.

https://www.ebay.com/itm/Acme-537-13...QAAOSwALhaXrX1

https://www.researchgate.net/publica...gh_Tip_Loading

https://www.nap.edu/read/5870/chapter/64