Originally Posted by
FH1100 Pilot
” but FOREVER we Yanks have called SWP "a condition in which the rotor is re-ingesting its own tip vortices."
Which is why the FAA uses the VRS and SWP terms interchangeably: For all intensive purposes they are the same thing in our book. To hijack one of the term (SWP) and make it mean something else is just...I dont' know...weird.
FH1100 has just helped me understand something - I was just about to make a smart Alec comment about “but Sir we’ve always said that the earth was flat” but then an epiphany; my understanding while following this thread was that the FAA was not differentiating between VRS & SWP because they didn’t acknowledge the difference, but reading FH1100’s post I now realise that the FAA understands that the rotor disc is reingesting it’s own vortices, they just call it SWP. Yes the disc is in a vortex ring state, they get that, but they refer to the condition
based on what the aircraft is doing, not what the rotor disc is doing.
Did I get that right FH1100? It all makes sense to me now, I can relax & feel better knowing that the FAA aren’t aerodynamically challenged.