So, I mess up my pre-flight planning and make an approach to a OGE hover a few hundred pounds above my RFM MAUM for OGE hover at that temp and pressure. I am aiming for a 70' hover to confirm my ground position before descending vertically into a smallish LS with some obstacles around it.
As I get to 70' in a level decel and start to lose translational lift, I raise the lever and pull as much power as the engine will give me but the aircraft starts to sink - I raise the lever some more but the engine has topped out and I hear the Nr start to decay and I keep going down - I am clearly going to hit the ground but why?
Is the answer
a - I have settled with power because I don't have enough to hover OGE but tried it anyway?
or b - I have entered VRS because aerodynamics weren't on my side today?
I have ended up in an overpitching state trying to arrest the descent but I am going down with full power applied and the Nr decaying. I haven't caught up with my downwash because the RoD is fairly low and I might just be saved from a hard impact by ground effect.
On a different day, I have done my pre-flight planning perfectly and I know I have OGE hover performance plus some in hand for the wife and kids. I make my approach with a slight tailwind that I didn't notice and I end up a bit steeper on finals to my OGE hover point than I intended. I have some forward speed when I look out of the window so I accept the higher rate of descent thinking that a combination of flare effect and power will sort things out near the bottom. I feel a sink and some vibration I don't much like so I grab a handful of lever - the aircraft shakes some more and sinks a bit faster so I add more collective. Suddenly I feel as though I am falling out of the sky and the ground is coming up really fast. I am clearly going to hit the ground but why?
Is the answer
a. I have run out of power and am therefore settling with it?
or b - I have entered VRS because I didn't realise I was downwind and let the external references fool me into thinking I still had forward airspeed on? I allowed a high RoD to develop with very low airspeed and tried to recover with lever. I may or may not end up with max power applied and I might even get to the point where I get Nr decay as well but that is a symptom a long way down the list and not the cause of my problem.
There may still be some who can't tell the difference and all I can say is I don't want to go flying with you.
This first one is called Full Throttle, which if you continue pulling, will lead to Low-rpm Rotor Stall, which would most likely happen before you reach settling with power (vortex ring state)!
In the second one you have clearly induced settling with power (vortex ring state) because you chose to ignore the warning signs and began settling into your own downwash!
Perhaps if we gave you all a Full Throttle Lite that would end your confusion?
