First, let’s back up to what you as an instructor already know – 1. There are a lot of things happening between the turn from downwind to base and the rollout after touchdown; 2. Events seem to be changing more and more dramatically as the process continues; 3. Events are occurring faster than you can explain them to your student, and one change seems to affect everything else; and 4. The airplane is lousy conference room. I have a few “givens” which I am guessing that you already know, and we will go from there.
In order to perform consistent, successful landings, we need to start from the same point in space at the same airspeed every time. We know that this point in space differs with airplanes and with the wind, and I will let you determine what works for you. For me, in an aircraft the size of a Cessna 172 or Piper Cherokee or smaller, that point in space is 800 – 1,000 AGL, about ¾ of mile offset from the runway, and about ¾ of mile past the end of the runway. And the airspeed is roughly the top of the white arc. See what works for your situation, and then make whatever changes are necessary. Some instructors like their students to carry power through the entire approach, and adjust as necessary; some teach that the power should be retarded to idle and then added as necessary. There is nothing wrong with either approach, but consistency is the key. And while it is definitely possible to make bad landings after a perfect downwind-to-base turn, it is very difficult to make consistently good landings if this point in space is incorrect or inconsistent.
Second, I spend a good deal of time on the ground with my toy airplane, explaining what I am doing. I also often draw a runway and traffic pattern on the ground, big enough to walk on, and I “walk” the pattern.
Now, here is what I perhaps explain differently. You as a pilot and as an instructor, are continuously looking at two things from the point that you pull the power back to turn base until you touch down – runway, and the airspeed indicator. And you are probably saying to the student, “Runway, airspeed. Runway, airspeed.” And the student is saying the same thing back. But trust me here, the student doesn’t have the slightest idea of what you mean. Because you have compressed so much of your own thought processes into these two words, you do not realize what you really mean. Here is what is really going through your own mind, which is what you want the student to understand.
When you say “airspeed” you are asking yourself – What is the current airspeed, and how does that compare to what I want? (And the student has to know what airspeed you expect her to fly.) What is the trend of that airspeed? Whether or not it matches my desired airspeed, is it increasing, decreasing, or stable? And if it is changing, how fast is it changing?
And “airspeed” is the easy word. When you say “ runway”, you are asking yourself three times as many questions. Are you on the glide slope you want, or are you above or below that angle? And what is the trend? And how fast are you changing from desired glide slope? Are you lined up with the centerline, and what is the trend and speed of change? And is the airplane aligned with the runway, and what is the change and speed of change.
After I talk about this a bit, I point out a fact that you know as an instructor. Even though you may have three of those four situations stable, changing the fourth one is going to affect the other three. And then it is all going to change when you bring the nose up to flare. No wonder the student says, “ARRGH!”
So I will explain this to the student, and then I will tell him that we are only going to work on parts of these at a time initially. And this is an iterative process. The first time you discuss these concepts, you will see a vague nod. It is only after the student sees what is happening, and then hears you discuss them again, will they start to sink in.
For the first few patterns, we may work only on runway alignment and keeping the aircraft straight with the centerline. Most pilots can see when they are off centerline, or when their nose is not straight down the runway, but they don’t really become aware of the condition until very short final. Our challenge is to get them to see that even as they are rolling out of the base-to-final turn. And here is how I do that.
I emphasize that when I am talking about looking at the runway, there are really two runway “pictures” that I am talking about. And in this phase, the runway picture I am talking about is the entire centerline. (Later, I will talk about aimpoint) I tell the student that I want them to visually line up the far of the runway with the near end of the runway. Then I show them the point on the airplane nose that is in front of their eyes (not the center of the cowling) and help them see that they will be on the runway centerline when the far end, near end, and point on the cowling are all on a straight line. It is nonsensical to talk about lining up with the approach end of the runway. No matter where you are in space, if you are flying to a point, you are lined up with that point. You are only lined up with the centerline if you have all three points lined up.
Now, as you know, when the student corrects for the crosswind with rudder and aileron, the increased drag is going to cause an increased sink rate. For this point in the training, I just help the student add a little power and I don’t worry too much about that.