"John" wrote in message

Nope, those four fans were running at a pretty good clip. No wind
involved there. Besides, with the size of those things, it would take
a hurricane to keep them turning for two hours.

Rotor sections are *extremely* finely balanced, else they would vibrate the
engine right off the wing at operational speeds. What this means is that
the blade wheels will turn freely with very little force applied. A light
breeze will suffice, no hurricane required. In my experience, more often
than not you'll see these things turning (at least with large fan engines)
if there's any breeze exposure at all.


Regards,

John Gaquin
B727, B747