CFI: Brian W.
Aircraft: Robinson R22 Beta II
Aircraft ID: N2223P
Duration: 1.5hrs
Cumulative Time: 83.0hrs
Well, not a total failure, but I have to retake it. Pretty big let down, and I'm pissed. I want to fly well, and today was certainly an off day. The mistakes I made were stupid, plain and simple.
Mistake 1) Made a poor weather decision.
This time of year, in Oregon, is rather odd - weather wise. You swing from perfection to total crap in an hour. It just so happened that I was on the down swing for this progress check. Morning started out nicely and it turned crappy fast.
Skies were overcast at 4000ft (more than enough for this check) and wind was 9knots. A little bit of wind is not bad, but this was about where I start to think... "eh... maybe a pain". Not anywhere near problematic, but not a calm day either. The biggest issue with wind is gusts, and changing wind direction. Radar did show a storm brewing about 12+ hours away, so I decided to go for it.
Mistake. Not that it was unsafe, but why should I shoot myself in the foot? I should have just called it off and waited for a better day. Stupid.
Mistake 2) Selection of a bad helicopter.
2223P sucks! Well, not really, but the radio is crap and it pulls a LOT of power in a normal hover.
First, the power. Since I'm still pretty heavy, and you can't pull too much power in flight (for safety reasons), you need to keep an eye on your gauge. In most helicopters a casual glance down at your manifold pressure gauge is enough... in 2223P... you have to STARE at it. It is always on the edge. I spent a lot of my brain cycles on this gauge... and I needed them elsewhere.
Next, the radio. I literally had to make 30% of my calls twice... the tower could not hear me. Again, it happens from time to time, but having to do things twice in a testing situation is rather unnerving. Time for a new radio, 2223P.
Mistake 3) Was not completely aware of wind.
The first two... luck of the draw.
This one... my real and honest errors. The wind changed on me by 180º, mid flight. It happens, but I'm supposed to be able to recognize this. Not only from the behaviors of the helicopter, but the fact that there are windsocks and other wind indicators out there.
See, a helicopter can deal with almost any wind from any direction - in flight. At takeoff and landing, wind is a very big deal. Since a helicopter generates its own down-wash turbulence, you get the best lift if you are moving in such a way where your motion moves (or if the wind blows) the down-wash out of your way. If the wind is head-on, your down-wash is blown away... a nice thing - out of your path of travel. If you have a tail wind, it blows it right into the air you need to be in a few seconds. Making your point of greatest lift farther away and, therefore, take-off harder. If you know it is there, you can deal with it... sometimes you will just have to deal with it. But it makes things difficult and potentially dangerous.
Same thing for a landing. I've talked before about settling with power - the condition where the helicopter gets caught in it's own down-wash... and loses lift quickly. This is really the most dangerous and common thing out there.
Anyway, the red/yellow/green diagram above is literally what I think of when making wind decisions.
Green, is good news. If the wind is coming from any of those directions, you are good to go. You'll get into ETL easier (get maximum lift here), and you don't have to worry about the helicopter being blown around.
Yellow is iffy. When the wind blows from this direction you can, potentially, lose some of your tail rotor effectiveness; LTE - Loss of Tail-Rotor Effectiveness. The wind blows the rotor-tip turbulence vorticies into your tail rotor. This, in turn, reduces the force generated by the tail rotor and you will yaw right. It is easy to compensate for this... you just have to be aware and ready for it. Otherwise you yaw to the right abruptly.
Red... red is bad news and should be avoided whenever possible. Couple things can happen from the different areas.
If a strong wind is blowing from 270º you are in a settling with power state in the tail rotor. The tail rotor's job is to produce thrust away from the blades and to the left... thus counteracting the torque from the main rotor. The main rotor is turning counter-clockwise, and therefore the helicopter wants to turn clockwise to counteract that. The tail rotor is pushing the opposite direction - keeping you straight. If a strong enough wind forces the turbulent air back into the tail rotor blades... it "falls" through the turbulent air it just created and you start yawing to the right.
If wind is coming from behind, pretty much at any angle between 270º and 90º your helicopter acts like a weather vane and tries to flip around and point into the wind. Makes it very hard to maintain your heading.
If you have wind from behind, and are trying to take off it is quite hard to find ETL, or the point where you have increased lift. If you happen be taking off with a tail wind... and you do get into ETL and start to climb... then a gust of wind appears out of nowhere you drop out of ETL and lose that lift. Bad.
If you are trying to land in a tailwind, you are very susceptible to settling with power. You just don't know where ETL is and not having that information is very dangerous.
During my flight, the wind literally flipped around on me... full 180º change. So, I was coming in for a landing with a headwind on one approach... all was good. Took off, went back around, and all of a sudden it was a tail wind.
My real mistake... is not checking the wind sock constantly. To my credit, I was watching a smoke plume about 1 mile north of the pattern. But, apparently the wind shift was a local phenomenon and my smoke plume had no bearing on where I was flying.
Back on the horse...
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