【高级听力】（文末附视频）Why Takeoff and Landing Are So Dangerous
Why Takeoff and Landing Are So Dangerous
《文 末 附 视 频》
This may not be a word-for-word transcript.
Narrator: 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 to [be] 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.
Anthony 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…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.
Anthony Brickhouse: We’re slowing down, and we’re getting the aircraft down to the ground. And since you’re already slow, any…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.
Anthony 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.
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