Five peculiar things you didn't know about landing a plane (TRAVEL)
Landings are by definition a transitional experience. We’re guiding a fast, powerful vessel from one unique realm, the air, onto the ground, which is quite another.
It’s not surprising, then, that the task of landing a plane has so much to teach us about flying in general. Nor is it surprising that one of the biggest challenges of writing a book like How to Land a Plane is that there are far too many fascinating details to share than there is space on the page.
Here to get you started, is my A-list — the five remarkable facts about landings that most amazed me when I trained to be a pilot. These facts are something to think about anytime you’re in the window seat and gazing out at the wonder of your approaching world. They might be of interest, too, if there’s a professional flying lesson in your not-too-distant future. As someone who loves to fly, I hope there is.
1. Planes are pointing upwards when they’re flying downwards
To new pilots, one of the most surprising facts about flying is that to get to where you want to go, you typically must aim the aeroplane somewhere else. Consider that the nose of a plane is usually pointing upwards even when a plane is in level flight, which is why it’s usually harder to walk toward the front of a plane than it is toward the back, and also why cabin service trolleys need good brakes.
How can this be? The easiest way to imagine it is to think about wings as if they’re water-skis. When a water-skier is moving absolutely level across the surface of a lake, his or her skis are nevertheless inclined upwards. It’s the same for wings. In fact, on an aeroplane like the 747, pilots may be pointing the nose slightly skyward even when the aircraft is descending in the final stages of the approach to a landing.
2. And pointing left when they're moving right
This may sound even more confusing than the upwards-downwards conundrum. But it won’t to those of you who are sailors, nor to those of you who may remember those maths problems from school, in which you had to calculate the exact angle at which you’d need to swim in order to cross a fast-flowing river.
In the sky, of course, the river we’re talking about is better known as the wind. When a plane is landing in a crosswind, pilots will commonly aim the plane into the wind, a manoeuvre that will ensure that the aeroplane’s path over the ground takes it directly to the runway. This technique is effective but challenging.
The required angle depends on the speed and direction of the wind, which may change throughout the approach, especially in gusty conditions. In strong winds and thick, low cloud, it also means that when the runway finally appears in the cockpit windows, it can be markedly off to the left or right of the nose.
3. Runway illuminations are incredibly complex
Runways, you’ll be glad to hear, have remarkably complex lights built into them (and around them). These lighting systems form well-defined patterns and can start hundreds of metres before the runway itself. The definitions and drawings of the lighting patterns fill whole pages of our manuals (or whole screens, I should say, on the iPads that hold our manuals now).
Perhaps you’re lying awake at night wondering about, I don’t know, ‘ALSF-2’ lighting? Why, that’s ‘Standard 2400’ high-intensity approach lighting system with sequenced flashers (Category II configuration)’. But the snazziest lighting system, and one of the most useful, is one called ‘the PAPIs’, or Precision Approach Path Indicators.
PAPIs are sets of red and white lights that show pilots our position with respect to the ideal vertical path that slopes from the sky down to the runway. Three white lights and one red light means you’re slightly above that ideal path; three reds and one white indicates you’re slightly below it. Two reds and two whites? That’s spot on. The geekiest pilots (i.e., me) might even use that expression—‘yeah, two reds, two whites’—to indicate that something we’re working on far from any airport or aeroplane—such as the timings for a complicated meal, or the budget for a home renovation—is looking good.
2. And pointing left when they're moving right
This may sound even more confusing than the upwards-downwards conundrum. But it won’t to those of you who are sailors, nor to those of you who may remember those maths problems from school, in which you had to calculate the exact angle at which you’d need to swim in order to cross a fast-flowing river.
In the sky, of course, the river we’re talking about is better known as the wind. When a plane is landing in a crosswind, pilots will commonly aim the plane into the wind, a manoeuvre that will ensure that the aeroplane’s path over the ground takes it directly to the runway. This technique is effective but challenging.
The required angle depends on the speed and direction of the wind, which may change throughout the approach, especially in gusty conditions. In strong winds and thick, low cloud, it also means that when the runway finally appears in the cockpit windows, it can be markedly off to the left or right of the nose.
3. Runway illuminations are incredibly complex
Runways, you’ll be glad to hear, have remarkably complex lights built into them (and around them). These lighting systems form well-defined patterns and can start hundreds of metres before the runway itself. The definitions and drawings of the lighting patterns fill whole pages of our manuals (or whole screens, I should say, on the iPads that hold our manuals now).
Perhaps you’re lying awake at night wondering about, I don’t know, ‘ALSF-2’ lighting? Why, that’s ‘Standard 2400’ high-intensity approach lighting system with sequenced flashers (Category II configuration)’. But the snazziest lighting system, and one of the most useful, is one called ‘the PAPIs’, or Precision Approach Path Indicators.
PAPIs are sets of red and white lights that show pilots our position with respect to the ideal vertical path that slopes from the sky down to the runway. Three white lights and one red light means you’re slightly above that ideal path; three reds and one white indicates you’re slightly below it. Two reds and two whites? That’s spot on. The geekiest pilots (i.e., me) might even use that expression—‘yeah, two reds, two whites’—to indicate that something we’re working on far from any airport or aeroplane—such as the timings for a complicated meal, or the budget for a home renovation—is looking good.
4. Aeroplanes tell you to decide - out loud - just seconds before landing
An approach to a runway typically features what’s called a ‘decision altitude’ or a ‘decision height’. When pilots reach this decision point, we need to be able to see the runway or its associated lights in order to continue the approach, if not, then you must prepare to ascend again and perform a go-around. This decision point is so important that a computer may announce it out loud in the cockpit.
On many aeroplanes, such as the Boeing 747, the voice says just one word, loudly and clearly: ‘Decide!’ It’s so memorable (and important) that any pilot can probably reproduce its intonations and pitch exactly. It’s even on YouTube: ‘Deee-CIDE!’ And if you’re not a pilot but you like the sound of a ‘decide’ call in life, you’re not alone. When I tell my friends in other professions about it, they often lament that their meeting rooms don’t have a ‘Decide’ announcement, one that would be made automatically at a pre-determined point in a meeting—eg, after 30 minutes of discussion.
5. Even when you’re flying, you can be resting on the ground
The phenomenon known as ‘the ground effect’ is one of the most remarkable things a pilot can experience. A wing can be thought of as a tool for pushing air downwards (think again of those water-skis…) When a plane is at high altitude, there’s an awful lot of airspace between the wing and the ground. But as a plane descends, the air between the wings and the ground becomes increasingly compressed. Why’s that? The classic way to think about ground effect is to imagine that as you get closer to the ground, the air below the wings can no longer ‘get out of the way’ in time. The result is called the ground effect.
It’s often compared to descending onto a soft cushion of air, and pilots must be prepared to lower the nose a bit in order to maintain our rate of descent as we enter it. The ground effect isn’t something you can usually feel in the passenger cabin, but it’s nevertheless something amazing to ponder. The next time you’re sat in the window seat, look down at the earth about 15 or 20 seconds before touchdown. In one sense, at least, you’re already resting on the earth; you’re already home.
Mark Vanhoenacker is a Senior First Officer for British Airways and the bestselling author of Skyfaring. His latest book, How to Land a Plane, is published 21st September.
An approach to a runway typically features what’s called a ‘decision altitude’ or a ‘decision height’. When pilots reach this decision point, we need to be able to see the runway or its associated lights in order to continue the approach, if not, then you must prepare to ascend again and perform a go-around. This decision point is so important that a computer may announce it out loud in the cockpit.
On many aeroplanes, such as the Boeing 747, the voice says just one word, loudly and clearly: ‘Decide!’ It’s so memorable (and important) that any pilot can probably reproduce its intonations and pitch exactly. It’s even on YouTube: ‘Deee-CIDE!’ And if you’re not a pilot but you like the sound of a ‘decide’ call in life, you’re not alone. When I tell my friends in other professions about it, they often lament that their meeting rooms don’t have a ‘Decide’ announcement, one that would be made automatically at a pre-determined point in a meeting—eg, after 30 minutes of discussion.
5. Even when you’re flying, you can be resting on the ground
The phenomenon known as ‘the ground effect’ is one of the most remarkable things a pilot can experience. A wing can be thought of as a tool for pushing air downwards (think again of those water-skis…) When a plane is at high altitude, there’s an awful lot of airspace between the wing and the ground. But as a plane descends, the air between the wings and the ground becomes increasingly compressed. Why’s that? The classic way to think about ground effect is to imagine that as you get closer to the ground, the air below the wings can no longer ‘get out of the way’ in time. The result is called the ground effect.
It’s often compared to descending onto a soft cushion of air, and pilots must be prepared to lower the nose a bit in order to maintain our rate of descent as we enter it. The ground effect isn’t something you can usually feel in the passenger cabin, but it’s nevertheless something amazing to ponder. The next time you’re sat in the window seat, look down at the earth about 15 or 20 seconds before touchdown. In one sense, at least, you’re already resting on the earth; you’re already home.
Mark Vanhoenacker is a Senior First Officer for British Airways and the bestselling author of Skyfaring. His latest book, How to Land a Plane, is published 21st September.
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