Sunday, January 20, 2008

Dumbest Argument in Aviation

One of the more meaningless debates in aviation concerns how to land tailwheel airplanes. I’ll get to why in a little bit.

As I mentioned in an earlier post, airplanes that have nosewheels are supposed to be landed at (or near) a full stall. As the airplane slows just over the airport boundary, you come back on the control wheel and keep coming back, “flaring” over the runway. Ideally, you end up being a few inches over the runway at the time the airplane is slow enough to quit flying, so you land at the slowest possible speed. That then means you use the least amount of runway to stop and, if you can, you may not even need to use the brakes to slow by the time you reach the taxiway turnoff.

Tailwheel airplanes can land like that, in what is often called a “three-point” landing, because you touch down on the mail wheels and the tailwheel at the same time. The other technique is known as a “wheel landing.” In a wheel landing, as you come in to the flare, you bring the airplane level to the ground and touch the mainwheels only. You then move the control wheel (or stick) forward so that you raise the tail just a little. As you slow down, you then bring the stick back and bring the tailwheel onto the runway.

Some say that wheel landings are just wrong. Others point out that in a properly-executed wheel landing, you can maintain control in a crosswind a bit better than you may be able to maintain in a “stall it out” 3-point landing.

I think the argument is bogus. First off, there are airplanes that can (or should) be landing only one way. A lot has to do with the geometry of the landing gear. Some models of the Pilatus Porter have the main wheels so far forward that it probably isn’t a good idea to try a wheel landing on them. A Grumman Bearcat has such a large propeller that if you try wheel-landing one, you may smack the prop.



On the other hand, old hands at flying the DC-3 say that while you can try to land a DC-3 in a 3-point landing, the airplane eventually will bite you, hard. Some models of Cessnas and Citabrias can be devilishly hard to wheel land. The main gear legs are one piece of spring aluminum; if you plunk it down hard on the main gear, it will bounce impressively.

Second, it’s often a matter of pilot preference and technique. Some airplanes don’t care. Some pilots don’t.

The bad thing about wheel landings, though, is that they can be executed at much higher speeds. Landing on a runway faster than you need to is usually not a good idea; the faster you are moving when you touch down means the faster things can go sour and, because you have more energy to dissipate, if they do go sour, the more likely you are going to seriously bend the airplane and possibly yourself. I have seen pilots land way too fast in wheel landings, to the point that they have to raise the tail a lot to stay on the runway.

That’s a recipe for disaster. You really don’t need to be going much faster to execute a wheel landing and in some airplanes, you don’t need to be going any faster at all. The primary thing, though, is to know your airplane and know how to land it. One size does not fit all, one technique is not necessarily better. A good tailwheel pilot knows both methods.

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