How to Land an Airplane

by Philip Greenspun, ATP, CFI; December 2009

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This is intended for airplane students trying to master the approach and landing flare.

You're probably working much too much too hard

Are you chasing airspeed down final, yanking the nose of the airplane up into a flare, pushing the nose back down and adding power, and putting in dozens of other flight control inputs during a landing into a steady wind? If so, you're working too hard.

Suppose that it were actually difficult to land an airplane; what would you expect to see? The answer is dozens of wrecked Boeings and Airbuses at the end of every runway at every big airport. Not every airline pilot is a hero and not every hero can be a hero every day. If it required heroic airmanship to land an airplane, the TV news would feature an airliner crash every day.

What's the secret? Flying a stabilized approach, i.e., doing less.

Example Stabilized Approach

Suppose that you're landing on Runway 10 at the St. Thomas, Virgin Islands airport (TIST; photo). For any non-pilots reading this article, let me explain that an airplane landing Runway 10 would be on a magnetic heading of approximately 100 and be approaching from the west. The approach is over the open ocean and then over a beach that is lower than the runway. Let's ignore any rocks or other islands and assume that we can start from 70 nautical miles away at 123' above sea level.

Let's plan our approach. The airport is 23' above sea level, which means that our airplane is 100' above the runway. We are in a trainer aircraft with an approach speed of 70 knots, which means that it will take one hour to reach the runway 70 miles in front of us. If we trim the airplane to hold 70 knots and set the power for a 100' per hour descent rate, i.e., very nearly level, we will have descended to 23' above sea level exactly upon reaching the runway threshold.

How hard would it be to do this landing? We set the trim and power an hour beforehand. We change nothing until we feel the wheels touch the pavement. Then we reduce power, apply the brakes, and turn off before the end of the 7000' runway.

Did we need to chase airspeed? No. We had a whole hour ahead of time to get the trim exactly right. The airplane flew itself to the runway. Did we need to flare? Not really. Our vertical descent rate was 100 feet per hour, less than 2 feet per minute. The landing gear for a typical trainer aircraft is stressed for a roughly 500' per minute impact. Did we land on all three wheels at once, possibly stressing the nosewheel? We only had 2' per minute of downward velocity so the stress on the nosewheel was no worse than running over a small bump.

Why was this operation so easy? It was a stabilized approach. There were no changes in aircraft configuration, power, or attitude shortly before landing. Nor were there big changes required after landing, other than pulling back power and smoothly applying the brakes.

What is a Landing Flare?

The landing flare is a maneuver that enables a pilot to reduce an airplane's vertical speed without applying engine power. The reduction in vertical speed is achieved by reducing forward speed. This releases kinetic energy that has to go somewhere and one of the places that it goes is arresting the plane's descent (if done from straight and level flight, the result is a balloon upwards).

How dramatic and precise must the flare be? It all depends on the vertical speed of the airplane. In our sea level approach to St. Thomas we had a descent rate of less than 2 feet per minute so we did not need any flare. If you can figure out a way to approach the runway with a low vertical speed then you won't have to do much of a flare.

The FAA is here to help

Can you get any guidance from experts in approaching with a reasonable vertical speed? The FAA has installed VASI, PAPI, and electronic glide slope systems at nearly all of America's larger airports. These are generally set up to guide the pilot down a 3-degree slope to the runway. This is the approach angle that the FAA considers safest for the most capable airplanes flown by the most experienced crews. If flown in your trainer at 70 knots of airspeed with a 10-knot headwind, that's 60 knots of ground speed, and you will need about 300 fpm, a very gradual descent rate, to hold the 3-degree glide slope (more).

My primary instructor, an ATP with 9000 hours, when I asked whether it might be a good idea to follow the PAPI on Runway 29 at Hanscom Field (KBED) said "The PAPI is a powered approach. If the engine quits, we wouldn't make it to the runway." The engine never did quit on any of those trainers and he never was able to teach me how to land, though. (In "Learning to Fly", I explain how I finally did learn (with a much younger and lower time instructor in the right seat).)

What do High-time Piston Flight Instructors Teach?

The most experienced primary instructors in piston aircraft often teach students to hold pattern altitude until they've turned base. Then while banking the airplane in a base-to-final turn (destabilization #1) they have the student chop the power to idle (destabilization #2), which results in a 900 fpm descent rate that would destroy the airplane if not checked prior to ground contact. The landing flare becomes destabilization #3 and must now be a dramatic change in attitude, precisely timed, so that the airplane arrives about 5' above the runway with a modest 50-300 fpm descent rate.

Why would an experienced instructor encourage beginners to attempt something so much more challenging than what airline pilots typically do? Ask and they will say that the steep power-off approach is to make sure that the airplane could still make it to the runway in the event of an engine failure during the landing approach. If you weren't using any power to land then the failure of your only power source won't be too bothersome.

Does this make flying safer? It certainly makes flying safer for the instructor, who spends 90 percent of his or her flying time in the pattern at an airport. What about for the practical pilot? You are getting a license because you want to take friends and family on 1.5-hour trips. The time spent on a landing approach is an insignificant portion of the total flight time. If the engine is going to quit it is very unlikely to quit during the landing; it just ran for 1.5 hours without a hitch! The destablized power-off landing will not make your flying safer. Your passengers do not want to experience a terrifying plunge towards the Earth (power-off descent) followed by a last-minute save (flare) by their heroic pilot. They want the flight to be as smooth and stable as possible.

A standard pattern

Before flying a stabilized final approach it helps to fly a standard pattern. At a typical airport with a piston pattern altitude of 1000' AGL, reduce power and begin descending when on downwind abeam the numbers of the landing runway. Turn base at roughly 800' AGL, which should put the numbers at a 45-degree angle behind you. This sets up the plane for a final turn at approximately 500' AGL. Due to all of the turns we can't call this pattern "stable" but we can make it standard.

Attitude Flying: Look out the window

The typical flight school these days operates very slow airplanes at airports with very long runways. In the owner's manual, the manufacturer will report that a test pilot was able to land the plane in 500' of runway. You have 5000' or 7000'. You do not need precise technique to make a comfortable and safe landing. The technique described here will always work. If done imperfectly the result will be a longer landing, but still well within the 7000' of runway available. (What if you don't have 7000' of runway at your training airport? When practicing landings for the first time, why not go to a nearby airport with the longest possible runway? Learning to fly need not include the fear of running off the end of the runway. If you want to learn how to land on short runways, you can do that after you learn to land.)

Work with your instructor to pick some reasonable power settings. In a plane with a constant-speed propeller this will be measured in inches of manifold pressure. Perhaps 20" is good for the downwind and then 13" when abeam the numbers and for the remainder of the pattern. On downwind, find a pitch attitude that will result in the airplane holding level. This might be 2 or 3 degrees nose up and might result in an 85-knot airspeed. After reducing power, trim for a lower airspeed, perhaps 80 knots. After turning final, trim for your final approach speed, let's say that it is 70 knots for your trainer. With full flaps applied the correct attitude might be 1 degree nose down. Whatever it is, once you are sure that the airspeed is reasonable, let's say 67-80 knots, ignore the airspeed indicator. Look out the window and concentrate on preserving the pitch attitude. Take your hands off the yoke or stick and see if the airplane will fly itself towards the first third of the runway (the "touchdown zone").

What if you miscalculated the downwind-to-base turn or the power setting and you're too high? Should you chop the power and try to set up the airplane for a steeper approach to the numbers? No. Go around and try again to set up something like the 3-degree glideslope that the big airplanes use.

With the airplane flying itself to the runway, you're spending 5 percent of your energy applying minor pressures to the stick or yoke so that the airplane stays at your desired attitude. The other 95 percent of your energy is available to enjoy the view, make sure nobody else is on the runway, conciously avoid fixating on the portion of the runway towards which your plane is hurtling, and notice that you've arrived within about 15 feet of the ground. Smoothly pull the power back to idle. Simultaneously, gently and slowly pull the airplane from its 1 degree nose down approach attitude to its 3-degree nose up flared attitude.

Assuming that you're flown a stabilized powered approach, that's all you have to do to land an airplane: pull the power back and pull the nose up 3 or 4 degrees.

Comparison with book numbers

If you or your instructor were watching you might have noticed that you chewed up quite a bit of runway. The owner's manual, pilot's operating handbook, or "book", said that at this weight and altitude and under these wind conditions, the plane could land with just 450' of runway. You consumed 3500'! Should you be ashamed? Absolutely not. First, if you buy aviation gasoline, the tax you paid on that fuel paid for the long runway. You paid for 7000' of pavement; why not use it? Second, the hero test pilot who generated the book numbers did not go to an airport with a 450' runway and trees at the end. He or she tested the tiny little airplane at an airport with a 10,000' runway. Ten landings were accomplished, ranging in length from 450' to 700'. As the best demonstrated landing was 450', that's the number that was written in the book. Even the test pilot could not replicate this performance on every landing.

Comparison with Conventional Stabilized Approach Criteria

In the world of jets and airlines, stabilized approaches are often required by FAA-mandated operating rules. For example, in visual conditions, the approach must be stabilized at 500' above the runway or the pilots will initiate a go-around. What does stabilized mean to the jet crowd? The airplane is fully configured, with whatever flaps and gear settings are used to land. The engines are at a low-to-medium power setting and won't have to be adjusted until just before the flare and landing. The airplane is lined up with the runway and on a 3-degree glide path.

Implicit in this concept of stability is a requirement that the landing flare not be too dramatic. The pilot should be able to "fly the airplane onto the runway" with a resounding but not damaging thud. This is indeed how the "autoland" systems on airliners work. Following a stabilized and powered approach, a landing flare shows good pilot technique and is gentler on the equipment but it not necessary for safety.

The concept of stability in this article explicitly extends to one more phase of flight: the landing roll. The landing will be easier and safer if there are few changes from final approach to landing roll. The only changes should be a slight increase in attitude, a reduction in power, and the application of brakes.

Landing Higher Performance Airplanes

If you expect to move on to faster airpanes, such as the popular Cirrus SR22 or one of the new very light jets, learning how to land a trainer from a stabilized powered approach is much better preparation than dead-sticking a slow forgiving airplane.

Improving Your Landings

If you didn't touch anything for the last 500', arrived in the touchdown zone, stopped before the end of the runway, and didn't break anything, your landings don't need improvement. If you went around when you weren't properly set up for landing in the touchdown zone, your judgement doesn't need improvement. Through simple repetition your flares will become more consistent and there will be less of a thud when you hit the runway. Your landings can't get any safer, though, because you have already achieved all of the critical elements of safety for landing a light plane at a big airport.

If you want to visit smaller airports with confidence, you'll need to work on two skills: better control of arrival point and better control of airspeed. Superior control of arrival point comes naturally with experience. You aim at a spot just before the runway numbers, try to keep that spot in the same place on the windshield of the airplane (using power adjustments), and you will tend to touch the wheels down just after the runway numbers rather than "somewhere in the first 2500'". Most student pilots attempt airspeed control by staring at the airspeed indicator and making rapid pitch adjustments in response to airspeed changes. This is called "chasing the needles" and leads to massive attitude excursions. Try to remember that the instruments lag the airplane's attitude by at least a few seconds. The right way to control airspeed is by looking out at the airplane's nose against the horizon, not by looking at the airspeed indicator. Almost every student pilot learns this for flying around at 3000' above the ground but then forgets it when on final approach to a runway. Hold a constant attitude for 5 seconds and then glance at the airspeed indicator to see if you should consider making a small adjustment in attitude. If you can arrive on the runway numbers at the manufacturer's recommended airspeed, +/- 3 knots, you will have the airplane stopped in a remarkably short distance.

Remember that this a refinement, something to worry about when you're ready to take your Private checkride, not something to obsess over during your first hours of instruction.

How do the nation's best and most experienced pilots do this? They work for airlines, which are required by FAA regulation to plan flights only to those runways where the plane can be stopped in 60 percent of the available runway. I.e., they give themselves a huge margin for error. When you get your pilot certificate and are considering taking friends to a tiny airport, try to remember that!

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Text and photos (if any) Copyright 2009 Philip Greenspun.
philg@mit.edu

Reader's Comments

I am sure Philip is right that a low angle of approach is safest for the recreational pilot. There is no question that this is the easiest way to land a plane.

As someone who learned to fly gliders first, this mode of landing takes does however take the fun out of it. Much more entertaining is to approach the numbers at 1000' AGL on final, then turn to exclaim to your passengers, "Oh my, it looks like it is time to drop this puppy." Then dial in full flaps and enter a steep dive with fully crossed controls approaching 100 knots if flying a 172. The angle and speed of the descent (2,000 fpm?) ensures that the ground will loom up in a way that results in paralyzing fear in most passengers, especially those experiencing a light plane ride for the first time. Many will never fly in a small plane again and thus measurably improve their life expectancy. Small planes are indeed rather dangerous.

-- Bruce McHenry, September 14, 2010

Hi there, my name is Marcos and I am a FI. I want to say that I really enjoyed reading your review about flying.

But I'm not writing to congratulate you, just to clarify that there are more things involved when I teach my students how to fly... Think about how scared you were on your first approach??? It's true and old RAF pilots will teach to fly in such a manner that if your engine fails your chances of "making it" are the best for you and your pax. And at least me, if that is what I teach my conscious would be ok.

Have you been during your training short on final, very high, short on speed or too fast and your instructor had to take control ???? Well , that's what is about, better with me than on your own.Learn to fail or fail to learn.

I felt a bit offended(joking), there is more behind that what you think, at least in my case. Also your approach at 100 fpm to make it more comfortable is good only if there is no terrain ( u come flatter),

being honest with you a 70 % or more of the instructors I know are not looking after students (so you are right), 15% don't know how to instruct and the rest are good. If you think you don't fly enough time as it to happen to you it's your choice. Look, putting your nose down shouldn't scare you having a good understanding on momentum " altitude is money in your bank , speed is cash in your pocket" , but you like me are humans and it's scary like your first approach but then becomes no scary anymore. I am teaching single engines and prob. it is what most private pilots fly; well there isn't much too say S.E. .... Won't talk about Murphys law !!! Haha never happened to me but... I will be ready if...! I mean , it's not dangerous, doing aerobatics isn't dangerous either. Well hope no one will get offended and... Good flight gentelmen !

-- Mark DF, March 25, 2013

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