Breath deeply and count..............................
OK..........mindfullness over.
Rotorbee - you disappoint me.
Bobakat:
When an a/c develops VRS or IVRS, 'stuff' happens inside the lift drag curve where big green arrows and vectors and angles of attack all start moaning and complaining they aren't happy and as a result of this quiet revolution going on around your rotor disc, the aircraft says F-u-*-k it, I'm outta here and goes into freefall.
No one else has come along and spoilt the party - it's all down to that nasty neighbourhood and bunch of trouble makers the "aerodynamic gang".
When an a/c develops SWP, you're in a different neighbourhood. You're in the engine neighbourhood - the hot gas clan - those nasty individuals who spend all day hitting that huge compressor at the back of the class.
The a/c needs to stop as it ends its decent to land or is approaching an obstacle and the hot gas clan come out in force until all of them that are available are hitting the compressor kid as hard as possible, to the extent where the engine says to hell with this excessive violence in my classroom, enough is enough, we cannot continue to produce the output you require from this compressor to bring the MASS of this a/c to a stop (before it hits the ground/obstacle).
Look at it another simplistic way:
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 sufficent 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 particulr AUM.
It is an engine thang! Nothing to do with little green arrows/updraft/alpha.
Learn the difference guys and don't show your ignorance in basic helicopter theory FFS.
Calm..............close my eyes.....relax........
