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Old 28th Nov 2017, 14:55
  #105 (permalink)  
FH1100 Pilot
Join Date: Nov 2006
Location: Pensacola, Florida
Posts: 670
In Post #41, TC writes a fixed-wing analogy to SWP:
You are landing your jumbo jet at Heathrow and for that given AUM you decide to apply maximum reverse thrust to prevent yourself running off the runway. But all the reverse thrust available is not sufficient to arrest the AUM in time to keep it on the runway. Your engines aren't powerful enough (IN THE REMAINING DISTANCE OFFERED) to arrest your particular AUM.

It is an engine thang! Nothing to do with little green arrows/updraft/alpha.
And see, this is why we Americans seem to be confused. Our FAA would not attempt to put a silly name on such a thing other than "Pilot Stupidity." Running off the end of a too-short runway doesn't deserve it's own term of excusability, if you will. You exceeded the performance limitations of your aircraft, simple as that, next!

Getting into a situation in which you're making too steep of an approach or too fast of an approach and the engine does not have enough power to stop you at the bottom is *not* a phenomenon worthy of its own category. It's just a dumb thing to do. You might want to call it "settling with power," and that term certainly seems to fit because blaming things on an invisible boogeyman makes you feel better, 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.
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