I could use the prop calculator for that but I'm not sure how it compares to real world data. According to the calculator the Mej 18x8 prop at 8500 rpms should do 18lbs of static thrust. That would be tasty on my 12 pound bird. I am sure it would be different airframe to airframe. For example if you have a Extra 260 with a big mouth of a cowl intake. Wouldn't that affect the thrust? We can throw the thrust numbers in if guys list it.