Landing is one of those skills that people find hard to describe. Like many motor skills, it's not just about remembering some rules. It's like building a new "circuit" in your brain: being able to judge the situation and respond almost mechanically.
The landing is usually described as having several phases: the approach, the hold-off, the flare, and the roll-out. The approach we've discussed before: it's getting into a stable descent in line with the runway. If you keep doing the approach, you'll fly straight into the runway threshold nose-first; so before you do that, you pull up so that you're flying level a few feet above the ground. People describe this in different ways, because they fly it in different ways. Some say you should start to level off at the height of the hangars, or the height of a double-decker bus: both of these are pretty high, so you'd have to level off very gradually to land safely from there. One of the Group instructors says you should start when you start to see the texture in the grass. He's getting on a bit, and maybe his eyesight is worse than mine: I found that following that advice left me always too high.
As you've already closed the throttle, once you're level, you start losing speed, so you have to keep gradually raising the nose to maintain height. This is the "hold off" phase: you're trying to hold the aircraft off the ground as long as possible. Up until now, everything is pretty much the same as a tricycle aircraft.
As you lose more speed and your attitude is increasingly nose-up, the increase in drag makes you lose speed at an increasing rate, so you progressively pull the stick further back. This is where the "hold off" turns into the "flare". From passing the runway threshold to flaring takes maybe 10 seconds: less if your approach speed was slow to start with. Now the stick is right in your belly, the nose is so far up that you're in the three-point attitude (with the mainwheels and the tail skid all level), and you can't do anything to avoid losing height. You "plop" down gently onto the runway: you're not flying any more, you're taxying, the same way you did before taking off.
It sounds like a lot of stuff: different phases, judging your height and sink rate, and at the same time keeping track of how much runway you have left and making sure you're on the centreline. But it's actually quite simple: it's just the transition from flying to taxying.
When you start your turn onto final, you're at the best-glide speed, you have the right attitude for a descent, and you have some height above the ground (but the height is decreasing). You want to end up moving slowly (too slowly to fly), with a constant height of zero, and in the three-point attitude, taxying along the runway centreline. All of the sequence of events I described above falls out logically from that change:
- You need to be on the runway centreline, so you get in line with it, turn towards it, and hold that track.
- You need to reduce your height to zero, so you fly almost into the ground.
- You need to reduce your sink rate (rate of descent) to zero before you hit the ground, so you raise the nose to the level flight attitude.
- You need to reduce your speed, so you keep flying level, letting the drag take energy away from the aircraft until it can't fly any more.
- You need to be in the three-point attitude, so once the attitude can't make a difference (you're too slow to climb regardless of your pitch), you pull the nose up to adopt that attitude.
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