Saturday, December 18, 2010

Landing practice under low clouds

Friday I went to Crystalaire to work with an instructor to prepare for my Commercial practical test. Although it was raining on the south-facing foothills as I drove up from Orange County, Crystal is in the "rain shadow" of the San Gabriel mountains and only had clouds. But very low clouds - so low it was not possible to do anything but pattern flights, and even on those we could not get above about 800 feet. (Fortunately in Class G airspace we just need to stay clear of clouds.) So that's what we did: seven low flights. This was our first time working together, and he's going to need to see if I'm flying to Commercial standards, so we would need to do this sometime anyway.

We did a mix of standard patterns, rope breaks, and abbreviated patterns. Sometime he gave me a target touchdown point and/or stopping point just after we released from tow, so I had to quickly plan my pattern and glideslope. (This may not sound like a big deal to readers who are power pilots, but remember that in a glider you can neither add power nor go around). The runway is a mile long, and there was very little traffic, so we could touch down at either end and roll to the far end if desired.

All my previous preparation for the Commercial test had been in our Blanik L13's. The Grob 103 is a slipperier ship, and has no flaps, so the energy management is different. I've flown it a lot, and have done some short-field landings in it at Hemet, but lots of my flights in it have been at Tehachapi where we also have a long runway. And many of my flights in it have been dual with other pilots, so I have fewer landings in it than I'd like. So I really have not done many "accuracy" landings in the Grob, nor have I ever slipped it very much.

I'd never done a rope break in the Grob before... this day I did two. Both went fine, except that my turn was not steep enough on the first one. In a high-L/D ship like this, you can really do a 180-degree turn from about 200 feet AGL and get back to the runway with excess height that you need to lose either with spoilers or a slip.

The final flight was a "no-drag-devices" approach. That means flying the whole pattern with no spoilers, only using a slip to bring it down. Again, I've done it in a Blanik before but not in the Grob. It really did not want to come down! I was in a full slip, giving it all the aileron and rudder that I could, and was still too high about 1/3 of the way over the runway. (It didn't help that I was letting my speed get way too high.) He took over and demonstrated that it's possible to get it into a deeper slip if you kick the rudder all the way over abruptly. Somehow that gives the fuselage enough momentum to carry it into a more extreme yaw than if you apply the rudder just as far but more gradually.

By the time I had put the ship away, had a debrief, and ate my lunch, the clouds were breaking up. But I don't think anyone else was around to fly. And the drive back down to the basin was again through heavy rain and fog. You can see it creeping over the mountains in this pic.

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