You don't have to watch many landings before you can spot those pilots who are out of the groove and are likely to have to take it around. You know that because, after you've watched awhile, you begin to associate the airplane's position in the air with the point where it will touch down-and you know where it has to touch down if the pilot expects to get stopped with only polite braking.
When you're watching other folks touch down, you begin to associate the amount of runway they leave behind on touchdown, or their speed, with the likelihood of their having an exciting rollout. The more runway they leave behind, the greater the likelihood that there will be tire smoke and histrionics at the other end. On a longer runway, of course, the only consequence of landing long is having farther to taxi back. Still, it's bad form to land longer than you need to-especially if you get in the habit of doing so, and then have to fly into an airport with shorter runways.
Of course, there has to be some sort of definition as to what is considered "long" and what is "short." At the same time, we need to understand that we're not using "short" in the same way that we do when discussing short-field landings. That kind of short isn't necessary.
The airplanes that most of us fly take a similar amount of distance to decelerate to a stop after touching down, and it's shorter than most people think. The pilot's operating handbook for a Cessna 172N, for instance, shows that at sea level and with zero wind, it takes about 550 feet of runway after touchdown to stop. That's an optimum distance, as flown by one of Cessna's test pilots, but even we mere mortals can come close to that. In fact, practically all of the more commonly available light aircraft will roll to a stop with only moderate braking in a thousand feet or less. Usually much less.
If that's the case, then why is a 2,000-foot runway (one of the more common shorter-runway lengths) considered by many to be such a challenge? The answer goes back to the amount of runway left behind on touchdown, and that goes back to the issue of putting the airplane where you want it on the runway rather than blindly accepting what gravity hands you.
Remember that we're not talking short-field approaches here. What we're addressing is simply trying to put the airplane on, or near, a given point in a normal landing. We're not talking about landing on the numbers every time. We're also not talking about putting the tires on the same crack in the pavement time after time. What we are talking about is consistently being able to put the airplane down in the first 500 to 600 feet of the runway regardless of the conditions or the runway environment. (Well, we could make an exception for badly deteriorated pavement near the runway end, and we must make an exception in the case of a displaced threshold.)
The concept of making a competition-style spot landing every time is good in theory, but what we're really talking about here is nothing more than flying the airplane with a reasonable level of precision which then results in touchdowns in the first part of the runway. If you touch down within the first 500 feet in most light airplanes, you'll easily stop by the time 1,500 feet of runway is behind you, and that's our goal-1,500 feet. Not many of us will be using runways shorter than that.
Why use 1,500 feet? If most airplanes will easily stop in 1,000 feet, why not always land in that distance?
The answer is one of personal choice. If you want to put the mains on the numbers and raise the level of precision to the point that we must land within 20 feet of a given mark, then that's great. It's better than great; it's terrific! But that's not for most folks, and in some situations may not even be safe.
This is especially true if the aiming point selected is the threshold.
If you're putting yourself right on the threshold then that means you're dropping through 10 feet just off the end of the runway. In most situations, that's no big deal, but it doesn't take much of a gust factor or turbulence to eat up that 10-foot margin. Air can be unpredictable, and there's no practical reason to put the airplane right on the threshold unless you're working a runway that's really short-1,500 feet or less-or you're flying a faster airplane for which the available runway length is marginal, which of course raises other questions.
If your goal is to use less than 1,500 feet of runway and you're flying something like a Cessna 172 or Piper Warrior, you don't need to hit the numbers. You just have to be down, rolling, and decelerating before there are 500 to 600 feet of runway behind you. If you really want to land short, leave only 300 feet behind you. Or 150 feet. Besides, once you raise your skill to the point that you're always down in the first 500 feet, then trimming that down to 200 feet occasionally will be a no-brainer.
So, what are we doing wrong that makes us miss that first 500 feet, and how do we fix it? There are a number of reasons too much runway is left behind, but the number one reason is that we aren't being specific about where we want to touch down. On top of that, even if we do have a mark on the runway picked out, we're not able to predict where our glideslope will take us in relation to that point.
Most pilots are approximate-not specific-about where they want to touch down, and they look at the runway, not a given point. They'll watch the numbers until they get fairly close, and then they'll shift focus and look at the entire runway. This is like removing the front sight of a rifle. Your accuracy goes downhill because you don't have something finite to use as a reference all the way to touchdown.
Pick a point
So, rule one in putting the airplane down in the first bit of the runway is to pick a reference point. That point should be the numbers. Whoa-didn't we just say that we weren't going to land on the numbers? That's exactly what we said. And we aren't. We're going to use the numbers to control our glideslope knowing that even though our glideslope is pointed at the numbers, when we break the glide and start the flare, we're going to float past the numbers at least 300 feet.
If we actually want to hit the numbers, we have two choices of technique: We can bleed off speed at the end of the approach, like a short-field landing, or we can pick a reference point short of the end of the runway and let our float carry us to the numbers. Both require careful monitoring of the airplane's attitude and speed so we don't drop on like a sack of potatoes or land short. This is not necessary for normal landings.
We're going to control our glideslope by using a tried and true reference technique: "If the numbers are coming toward you or going down in the windshield, you're high. If they are moving up or moving away, you're going to be short." This is the same technique you were taught at the very beginning of your flight training. The real question becomes, how do we make those corrections on final? We certainly can't raise or lower the nose to climb or dive off altitude because we're trying to hold a specific airspeed. So, what tools do we have to control the angle of our glideslope and either go up or down?
If we're high on glideslope we have three specific tools depending on the situation:
- If you're carrying power, obviously reduce it, but monitor the movement of the numbers carefully. Don't wait until they stop moving to add power or you'll sink through the optimum glideslope that will take you to the numbers. Ease the power back in while still a little high and creep down to the proper glideslope, where the numbers are stationary in your vision.
- If you don't have all the flaps out, drop the rest of them and see if that's enough to get you down to glideslope.
- A slip can be used anywhere in the approach to lose excess altitude, but make sure your airplane's POH doesn't carry a restriction against full-flap slips.
If you're low and the numbers are moving up, or away from you, then your options are limited.
- If in a slip, take out all or part of the slip.
- Use power, but use it sparingly, and don't wait too long. Better to use a little power early in the approach than have to slam the throttle to the firewall at the end to save your bacon.
A few paragraphs back we said there were a number of reasons why there's a tendency to land long, and number one is lack of a specific reference point on the runway. However, tied with that for the number-one position is poor airspeed control. Even if you do everything right in controlling the glideslope and the runway numbers look as if they are painted on your windshield, you can't expect the airplane to land where you want it to if you aren't holding the right airspeed.
If you're slow on approach, when you start to break the glide and try to settle into ground effect, you'll find that there isn't much ground effect to catch you and the airplane wants to settle on immediately. If you carry this to the extreme and get really slow at the end of the approach, you'll hit hard and maybe even land short of the runway.
Everyone who has ever flown has been cautioned against getting too slow on final. The universal response has been, "if slow is bad, then fast must be good and faster must be better." This is a major reason we see so many airplanes landing halfway down the runway, especially in crosswinds where some sort of old wives' tale must have pilots convinced that they are better off if they are really fast. Fly a fast approach and you can count on a long landing, period.
Simple physics dictate that airplanes that are flown fast will float forever. There is, for instance, no more delicate a dance in aviation than trying to get a 172 with full flaps to land when you're 10 or 15 mph fast. You play that hold-it-off-but-don't-balloon game as if you're teetering on a fence and trying not to fall off. It may take 15 seconds to get the airplane slow enough to settle on, and all that time runway is zipping under you at approximately 70 feet a second. So, a seemingly benign 10-second float causes 700 feet of runway to slither past.
If you're fast on final and carry that speed into the flare, you'll be lucky to touch down with anything less than 1,200 feet behind you. That can make a 2,500-foot runway look scary.
If you're going to put an airplane on the runway with any precision, you have to fly the final leg with precision. There are bound to be readers who feel as if we're making too big a deal out of landing on the first 500 to 700 feet of the runway (with allowances made for the approaches). Few general aviation pilots see runways much shorter than 3,000 feet, so where's the crisis? The crisis is this: If you get in the habit of landing long and fast, some day you're going to be forced into landing on a runway that is shorter than you're used to, and even though that runway isn't really short, your technique will make it short. Even with trees off the end of the runway, any Warrior or Skyhawk-type airplane can land with ease on a 2,500-foot strip. However, come over those trees even 10 mph fast and the other end of the runway will be in your face in nothing flat.
Although it is the amount of runway in front of you that counts, that is determined by the amount of pavement left behind you. Have you heard the expression, "There's nothing more useless than altitude above you, runway behind you, or fuel left behind in the truck"?
If you make it a rule to land with a minimum amount of runway behind you, you'll always have a maximum amount where you need it-out in front.
Budd Davisson is an aviation writer/photographer and magazine editor who has written approximately 2,200 articles and has flown more than 300 different types of aircraft. A CFI for 36 years, he teaches about 30 hours a month in his Pitts S-2A Special. Visit his Web site.
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Links to additional information about landing techniques can be found at AOPA Online.
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