Sunday, August 10, 2008

Steep turns

One of the requirements on the Practical Test Standard for the Commercial certificate is demonstration of steep turns. That means turns at a bank angle of up to 60 degrees. One trick that has been suggested to help gauge the angle of bank is to pick two screws on an instrument, diagonally opposite each other, and make them line up on the horizon. Using that measure, I realized some time ago that I usually don't bank very steeply, usually only up to 35-40 degrees even when thermalling. It just does not feel comfortable to bank more steeply.

So today that's what I planned to work on. Shortly after release I found a suitable thermal and intentionally banked steeper and steeper. I thought I remembered feeling that I would fall sideways toward the low wing, but that was not an issue today. This time I found two things that I needed to work on:

* The G force gets really noticeable beyond 45 degrees or so. If I recall correctly, it's 1.4 G at 45 deg, and 2.0 at 60 deg. When thermalling, we keep on circling for many turns, unlike when we turn just to change heading. So the G force is with us for a long time. Not a problem, but it takes some getting used to.

* I initially had some problems with speed control. In the PW5, at 60 deg, the optimal speed is 56 knots. It kept wanting to creep up to 62 kt or so, and it took a lot of effort to bring it back down. After some practice, I seemed to be more consistent.

After working a couple of thermals up to about 6800' MSL, I headed over to the hills to see if I could find some to take me higher. No luck - a lot of sink - and I ended up with just a 40-minute flight.

Earlier in the day, I spent some time briefing another pilot who's hoping to fly the PW5 soon. He's flown a single-seat glider a few times before, but it was quite a while ago. I recommended he work through Bob Wander's book "Transition to Single Seat Gliders", a terrific little book that really helps you get prepared in advance and suggests some maneuvers to practice in the air before your first landing.

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