CFI: Kristie H.
Aircraft: Robinson R22 Beta II
Aircraft ID: N7526S
Duration: 0.9hrs
Cumulative Time: 9.8hrs
Could not get a pattern today... again, so we had to head up to SPB (Scappoose airport code) for some flight time. SPB is an uncontrolled airport - which means there is no air traffic control tower to regulate flights in, around, out. This is primarily because the airport is low use and is used mostly by private pilots with their own planes. This also means, that you have to be on your toes and constantly be on the radio telling everyone what you want/plan to do. You also need to listen for the same communication. By far the most important thing at this airport is your visual sweep... apparently there are quite a few pilot that use this airport that are not up on their radio communications - some don't even have them turned on. So, very important to keep an eye open for them.
Flight to SPB was normal, but there was some low level clouds coming over one of the ridges along the way. We were at 2000ft, with plenty of visibility, so this was not a proble, but it was amazing to see the clouds spill over and into the small gorges in the area.
After some good pattern practice and even better hovering practice we did some "quick stops". This is the act of "coming in hot" (fast) towards your landing spot and landing in much less of a distance than would be necessary for a normal approach. (BTW, airplanes can't do this... obviously... only us. :) The procedure is basically this - aft cyclic to flare up a tad and lower collective pitch while applying right pedal. Kind of like sliding to a stop in wool socks on a kitchen floor. Or a sliding stop on skis. You are "leaning back" to direct as much force in front of you to slow down. As you sink down you ride ETL (Effective Translational Lift) to the ground and at the last few feet you raise collective and apply left pedal to come to a nice clean hover. That is the theory anyway. My first few were a little less graceful. Mainly in the hover at the end. I could come down, raise too much collective too quickly, yaw right and bounce back up in the air. Towards the end I think I figured it out, maybe B-?
One thing which I can take a way is that helicopters are dynamic beasts... they change their operation under various situations. Not just a little... significantly. So, what feels right at 3knots, no longer feels right at 10knots, etc. You need to adjust and anticipate what is about to happen so that you are ready to correct for it.
For example, when you are in your car... accelerating from 0 to 60 over a mile. You hold on to the wheel... keep it straight... and press on the accelerator.
Pretty simple. In a helicopter you start in a steady hover, transition to forward flight. If you remain at this speed you are taxiing and things are pretty much constant.Above a certain forward speed, say 10knots, you enter ETL. This is the state where the froward motion of your rotors is such that you are entering clean and undisturbed air... not just chopping up your own rotor wash.
This causes you to get more lift and reduce drag. As a result, you pop up... and I mean pop up rather quickly. The helicopter yaws left because not not only does the MR (main rotor) have better efficiency, the TR (tail rotor) does as well.
Since this always will happen, you need to correct for it if you want to stay in flight. Lower collective, forward on the cyclic and right pedal.
Kristie is good at it... I did not know there was even an effect of ETL like that... because she always anticipated it was coming and corrected instantly. That is, of course, until she told me that it was there and that she would stop correcting this time. Popped up, like a cork, flared back and spun 45ยบ left. Rather quickly, I may add.
I've gotten to the point where I can correct it pretty quickly... just not anticipate it yet.
It will come with time, I know.
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