为什么起飞和降落如此危险Why Takeoff And Landing Are So Dangerous

You are much more likely to die

eating a nice meal

than you are in a plane crash.

That being said, it happens.

At a rate at about one fatal accident

per 2.5 million flights.

And half of those accidents occur

during one very short phase of the trip.

Wanna know when you should be

the most nervous on your next flight?

Keep your seat belts fastened

and get ready for a bumpy ride.

Takeoff and landing are widely considered

the most dangerous parts of a flight.

But that's only partially true.

Let's take a look at this chart.

Boeing keeps track of fatal

commercial jet accidents every year

and categorizes those accidents by

when they occurred during the flight.

Boeing breaks down the average

one-and-a-half-hour

flight into eight phases.

But we'll just be looking at these five.

Starting at the beginning,

the takeoff and initial climb.

This phase takes up only

2% of the entire flight,

but it accounts for

14% of fatal accidents.

Which might not seem like a lot,

until we look at the cruising phase.

A plane cruises for more than half

of the one-and-a-half-hour trip,

but only 11% of fatal accidents

happen during this chunk.

So that leaves the final

descent and landing.

They take up about 4%

of the average flight,

lasting twice as long as

takeoff and initial climb.

But a whopping 49% of fatal accidents

occur in this short window,

making the final descent and landing

the deadliest part of an average flight.

So what's going on here?

Anthony Brickhouse: Typically

on takeoff and typically

on landing, the aircraft is

what we would call low and slow.

And when problems happen,

you don't have a lot of

time to actually react.

Narrator: When they're

cruising at 36,000 feet,

a pilot has the luxury of time

and space to course correct.

Even if both engines go out,

the plane won't just fall out of the sky.

It becomes a glider.

In this state, a typical airliner

loses about a mile in altitude

for every 10 it moves forward,

giving the pilot a

little over eight minutes

to find a place to land.

But if something goes wrong on the ground,

that window shrinks considerably.

For a typical commercial jet,

takeoff lasts only 30 to 35 seconds.

If an engine fails or

the landing gear jams,

the pilot has almost no time at all

to decide whether to take off anyway

or to try and wrestle a 175,000-pound

metal beast to the ground.

Rejected takeoffs are rare.

Brickhouse: Because when you're

blasting down that runway

at over 100 mph, things are

happening really quickly.

The decision to reject a takeoff

is a very intense decision

because you have to do

it below a certain speed,

otherwise, via physics,

you're not going to get stopped.

Narrator: If the plane

hasn't taken off or stopped

by this point, it's going

off the end of the runway.

Which, depending on the airport,

could mean sliding into an open field

or off a literal cliff, like at Colorado's

Telluride Regional Airport.

Its runway is terrifyingly sandwiched

between two 1,000-foot drops.

For dangerous runways like Telluride's,

airports will install

an engineered materials arrestor system.

An EMAS is a bed of materials

at the end of a runway

designed to collapse under

the weight of an airplane,

gripping its tires and

ideally bringing it to a stop

before it plummets 1,000 feet off a ledge.

It works similarly for

a landing gone wrong.

So, what is it about touching down

that makes it so much more

dangerous than taking off?

Oversimplified, it's

easier to make a plane fly

than it is to make it stop.

Brickhouse: We're slowing

down, and we're getting

the aircraft down to the ground.

And since you're already slow,

any wind effect or anything like that

could have more dramatic impact

than it would on takeoff.

Narrator: During a normal landing,

the pilot is communicating

with air traffic control,

lining up with the proper runway,

and informing the crew.

Similar to takeoff, but all while flying

toward the ground instead of away.

Brickhouse: Sometimes

it's a normal landing

where everything is going well

and something happens at the last second,

and it leads to an accident.

In other situations, there's already

an emergency on board the aircraft,

which has already complicated the landing.

And then they land, and something

unfortunately goes wrong.

Narrator: Statistics can be scary,

but they still say flying

is the safest way to travel.

And even if an accident were

to happen on your next flight,

you'd have a 95.7% chance of surviving it.