Wednesday, July 27, 2005

Fell off a Tractor in Tennessee, part II

After lunch, we made a plan that would take us from Lonesome Pine, first to Lee County, VA, then down into Tennessee to Hawkins County, then several other airports there, then back up toward home. We wanted to be reasonably careful about terrain, because the clouds had forced us down to 1,500 feet above ground for most of the flight since Hot Springs.

By this time, we were beginning to wonder if we'd ever find a calm wind at an airport. Every landing had been gusty. Lee Co. did the same. I had thought Lonesome Pine was in the middle of nowhere, until I found Lee Co. It is in the farthest southwestern part of the state, only a few miles from Kentucky to the north and Tennessee to the south. You know the picture of a standard "redneck" type of homestead (not that I'm trying to stereotype or claim it is bad)- old junk cars in the yard, tires, random other parts and junk sitting around. That's about all we saw from the air as we approached. This is an area that is truly a long way from home, in more ways than one. We made the landing, with the winds as gusty as we had come to expect that day, then took off toward Tennessee.

From here, the terrain began to come down a bit, allowing us a little extra room beneath the clouds. Hawkins Co. was not far away, and we entered the pattern for the left downwind on runway 25.

Here is where things changed a bit. Before I get to that, let me explain about that plane. The CT-SW is not the easiest plane to fly. DC had been flying a Diamond Eclipse from the beginning of his training, which is docile and very predictable. The CT was a different beast altogether. My first flight in it, when we got it from the dealer, was that it was amazingly touchy, and unpredictable. It is the only plane I have ever not been truly comfortable flying after ten hours.

One of the first things I noticed about it, after getting a little practice, was that it handled fine with 30 degrees of flaps, but going to 40 degrees made it a little less stable. The reality is that 40 degrees is simply too much for a plane of that size. At that point, the flaps cause so much drag, that the extremely low inertia of the plane causes it to try to stop flying. You really have to pitch nose down to keep your airspeed. Practicing stalls, I had been able to get down to 25 knots indicated airspeed with 30 degrees of flaps, but with 40, it wasn't possible.

This is not a new type of issue. Before the early 1970's (approximately), some of the smaller Cessna models came with 40 degrees of flaps. The 1966 Cessna 172H that I used to own was that way. The last bit of flaps was a great speed brake, allowing you to drop in from a very steep approach angle. But Cessna did away with that, turning out models that only went to 30 degrees, largely because of some accidents. An underpowered Cessna 150 flying on a hot day with 40 degrees of flap, might not be capable of even staying level with full power. And it is an accident waiting to happen if you are forced to abort the landing in that configuration.

Anyway, having played with the characteristics a bit on the CT, I decided that 40 degrees were really only beneficial for steepening the descent, but that my procedure would be to retract to 30 degrees before landing. The landing isn't difficult with 40, but it is more difficult than with 30.

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