Wednesday, November 4, 2009

Navigational Error

Well, this is embarrassing. I got all the kids to bed and Charlotte wasn't feeling well, so she went to be as well. I figured I'd get a short flight in before I turned in myself and decided to repeat an earlier flight from Dalton to Chattanooga, land, taxi to the end of the runway, turn around, take back off and fly back to Dalton. To make things a little more interesting I decided to do it with the current time (night) and with real world weather downloaded from the internet.

I selected my usually trainer plane, the Cessna Skyhawk, and the Dalton airport and started it up. Boy, was it dark. Looking around you could only see the runway lights blinking but I figured I could see more once I got in the air. I learned something the other day that makes take-offs easier. I've mentioned how you trim the airplane for a certain speed so you don't have to constantly hold the stick back during a climb for instance. It had not occurred to me before, but since you know the take-off is going to involve a long climb, why not trim the airplane BEFORE you head down the runway? In fact, there's a "Take Off" marker on the trim wheel that even tells you the ideal trim setting for the initial climb-out. I spent a minute adjusting the trim and then throttled up and headed down the runway.

I quickly got airborne and then only had to make slight adjustments to trim to get my climb just right. After that, I started looking around, but where I expected to see the big city lights of downtown Dalton, all I saw was darkness. Are we having a blackout or something, what gives? As I climbed higher, I got into the cloud cover which reduced visibility further. I could sort of see out the right side of the plane and started scanning for another airport that is off to the east on the route from Dalton to Chattanooga, but couldn't find it anywhere. I decided that if I descended from my current 4000 feet down to say 2000 feet, which should still be high enough to clear the ridge just east of Chattanooga, I could see better. Well, I tried that, but once out of the clouds I still could not see Chattanooga, but instead could see a ridge-line ahead that looked higher than it should.

At that point, it occurred to me for the first time to check the compass. Instead of flying a heading of approximately 330 degrees (NNW), I was flying the opposite heading of 150 degrees (SSE). Every other time I've taken off from Dalton, the computer has positioned me at the end of runway 33, heading north, but not this time. Probably on the earlier flights I had "fair weather" which meant no significant wind, which meant take-off direction didn't matter and the northward direction was the default. This time, with real weather and I guess a northward blowing wind, it put me on runway 15, heading south (same physical runway, just at the other end of it). In the real world, I would have taxied from the hangers to the runway and would have known where I was, but in the simulator I just took off assuming I was heading northward.

I quickly went to full throttle to avoid hitting the mountains (same range as Fort Mountain only farther south, just below Carter's Lake actually), and made a quick 180, heading back towards Dalton on my original intended course, but now with no intention of going to Chattanooga. I decided if I could get the plane back on the ground in Dalton I would call it a night.

After a few minutes I finally saw the lights of Dalton ahead and spotted the airport off to my right. I adjusted course, flew around south of the airport and then flew the "downwind leg" parallel to the runway to position for landing. Since I had taken off southward, presumably into the wind, I figured I'd better land into the wind as well since that results in a slower ground speed and thus a safer touch-down.

I flew out over Dalton, did another 180, made some more adjustments to line up on the runway, lowered flaps and headed in. One advantage of flying at night is that you can see the landing lights a lot better. At the end of the runway they have two sets of lights which can turn red or white. If you're on the proper glide slope, the top set (furthest away) will be red and the lower (closer) set will be white. "Red over white, you'll be all right". If you're too low, it's "red over red, you'll soon be dead", and if you're too hight, it's "white over white, you're out of sight" or something like that.

Anyway, I was red over white when I lined up, but then it went red over red so I had to throttle up, level off and even climb a bit to get back in the zone. I cut throttle again, added more flap and tried to bring it on in but then I got white over white, so I was too high. I slowed down more and probably over-compensated again as I ended up landing a little hard and right at the end of the runway. Since I only need about half the runway to coast to a stop, "too high" is a relative term. It really means too high if you need the whole runway to stop. I should have just ignored that white over white and continued the descent rate I was on and I would have been fine.

Anyway, I lived to fly another day, and as the saying goes, "a good landing is one you can walk away from; a great landing is one where you can still use the airplane again afterwards". I guess I'll file this one under great landing then and go to bed.

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