Seeing as everyone's talking about VRS & SWP (and i've got nothing to do right now) - I thought i'd chip in...
Many people use the phrases "Settling with power" and "Vortex ring state" interchangably - personally I think that they are two seperate but linked phenomena:
Imagine you come to a hover at 100ft above a point, you notice you are using 80% torque. To initiate a descent you have to reduce a bit so you go down to 78% and get a nice 100fpm descent rate. Easy.
Now imagine you approach the same hover but you can only pull 78% max - not enough to hover, but enough to give a stable 100fpm descent. As you slow down you hit the power limit and start to descend - "settle" - with power, but not out of control, you just dont have enough power to stop the descent.
This is what I would call "Settling with power" To stop it you still have to 'fly away' and get ETL to recover, but it is not uncontrolled or accellerating - indeed you'll almost certainly stop when you get ground effect again. Put simply, SWP is only having enough power to descend.
Anyone who's flown powerlines in a 300 will be familiar with what i'm talking about - all you need is an extra 1/2 inch to stay up, but you just don't have it...
Of course, should you allow yourself to settle at too high a rate - usually through bad power management (don't USE enough power) or exceeding the A/C's capabilities (don't HAVE enough power) then you'll experience VRS and the ATW (Associated Trouser-Washing) that follows...
Do you think i'm on to something, or talking bollocks?
Last edited by rudestuff; 9th Feb 2007 at 11:50.
Reason: spelling