Sunday, August 21, 2011

Crabby Crosswind Blues

Although conditions were pretty good at Sterling this morning, the weather at Spencer was bad and Ed couldn't fly out in time for our 8 am flight. So we rescheduled for 1 pm. When I got to the airport, a storm was on the way, winds were a bit gusty and variable, and Ed said "it's not going to be an easy day up there." He was right. We also had the less familiar (for me) runway 16 in use rather than the typical 34. Plus there were a few gliders around, so the gliders and the Piper Pawnee tow plane would be in the pattern with me. None of this should be a big deal, but I especially wasn't ready for the crosswind aspect, and I was a bit apprehensive. In retrospect I should have asked Ed to review and brief me on the situation, talk through what we would be seeing, and maybe even fly the first pattern and landing as a demo. I hadn't seen gusty crosswinds in a long time (maybe 2004!), but the weather was coming in, and if we waited, we wouldn't have much time to fly. So we flew.

I tried to use proper stick technique when taxiing out (no taxiway for 16 so you have to back taxi on the runway), stick forward when taxiing with a tailwind, plus some left or right stick into the wind as needed. Crosswind seemed to mostly be coming from the right on the approaches (maybe from due south) but the runway windsocks were variable and mostly down the runway. Takeoffs were mostly normal and mostly OK, though I was never really quite sure what I should be doing with the stick since the crosswind wasn't steady. The correct answer is "make corrections based on what you see and feel," so on the initial climb, I established a crab to the right, but I don't think I held the runway heading too well, and I didn't consciously adjust for it again until final. I should have been thinking about this both for the timing and the angles of my turns (e.g., when you turn left "crosswind leg" with a right crosswind with respect to runway heading, you have a tailwind on that leg and need to start your turn to downwind sooner). So without proper wind correction, my patterns ended up very wide and not very square.

With a (mostly) tailwind on the downwind leg, I should have started the turn for base earlier than usual, so I ended up quite far from the runway when I turned final (which I tried three different ways on the three landings, none of them lined up too well). But I finally got established on a crabbed final approach as shown in the hat cam video frame above (75 mph, 760 feet, 300 feet AGL). Due to the gusts, I probably should have flown the final a bit faster than the normal 65-70 mph, and I probably did since I tend to be fast on final. But the gusts were still a problem (aka "wind shear") and on the first approach, the right wing dropped pretty hard, and I was not quick enough to respond ("behind the airplane") and Ed added power and made the correction.

Once we were over the trees and coming down on the grass, we should have transitioned from the crab to a slip with the right wing low, and I think I did, though the crosswind was not very strong at the surface and it seems like the wings were mostly level on all three touch-downs. On the first landing, Ed said, "that was not bad, but you are still behind the airplane, you have to be quicker with the needed corrections." On the third landing I inexplicably released the back pressure just after touchdown, something you just can't do in a tail wheel airplane. Duh! We quit after three landings.

Overall an anxious but instructive session. Although you can't execute a fixed "crosswind plan" when the winds are changing, you do need to notice the trends, see what the airplane is doing, and proactively correct for it, and at least have in mind things like "hmm, from this drift it seems we have a crosswind from the right," and with this info in mind, make appropriate corrections on the rest of the pattern. On the first pattern, I should have figured out why I was so far from the runway compared to what I usually do - wind effects! Plan for them on the next one! The novelty of runway 16 meant that I didn't have familiar horizon and ground references for my pattern, though of course you shouldn't rely on such things since every runway is different. Crosswinds are always tough and I haven't really worked on this in years, but I really do need to get back to the "pilot in command" attitude and make the airplane do what I need it to do (which means noticing when it's not!).

Ed also commented post-flight that he has seen professional pilots (that ain't me) do more than one go-around on a windy, gusty day, not even attempting the landing until they have figured out what's going on and are satisfied they can make the landing safely. At least one of my three landings should have been a go-around. Aeronautical decision making!

0.7 hours dual in Citabria (8/21/11)