Wow -- I've been away for a week & this very interesting debate is still raging. Congrats JohnW on doing that lazy susan test. It is something that I was pondering, but you actually bothered to do it -- not to mention the more obvious tuft test.

It would appear that the effects of spiral slipstream are empirically confirmed. [sm=thumbup.gif] I guess that the fixation on full scale engineering has caused a few blindspots. Big planes need really big lazy susans so why bother with all of that costly, messy & unprofessional full-scale empirical testing when we can confirm numerically that P-factor is the culprit.

Hmmmmm. I bet that there is more comming.