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When Flying, Why is Taking Off More Dangerous Than Landing?

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Why is taking off more dangerous than landing?

Tom Farrier:

Landing is generally considered quite a bit more hazardous (and requires a bit more exacting handling), but both takeoffs and landings can have their challenges. Still, aircraft like to fly; sometimes it can be a little tricky to encourage them to stop doing so at the end of a flight, especially in the presence of unpredictable winds or slippery runways.

This is a graphic from my favorite go-to reference on commercial aircraft accidents, updated annually by Boeing but including all airliner accidents:

The shaded area under the aircraft silhouette shows the amount of time an aircraft spends in each “phase of flight.” At the top, there are two numbers worth looking at carefully. Final approach and landing is when 48 percent—essentially half—of all fatal accidents that have occurred from 1959 through 2016. By contrast, taking off and starting to climb is only about a quarter as hazardous (13 percent). These ratios used to be somewhat different; takeoffs used to see their share of accidents a lot more frequently than today.

The biggest challenge with taking off in the early days of jet airliners was the rate at which they could accelerate during their takeoff roll. Often, a lot of time was required between when the aircraft passed the speed at which the pilots were committed to taking off (V1) and when the jet actually could get into the air with a positive rate of climb. When an emergency would suddenly present itself in that window of vulnerability, sometimes there were no good options, and sometimes the pilots picked the wrong one.

One of the biggest ways pilots (and flight engineers in aircraft that use them) have to earn their paychecks is when something bad happens during a takeoff roll and they have to decide whether to continue the takeoff and deal with the problem in the air, or if the situation is critical enough that it’d be preferable to wrestle the fuel-laden beast on the ground and risk going off the end of the runway.

To try to address the need for added clarity in such situations, some of these early accidents led to recognition of the need for establishing a second speed benchmark (V2), which is the point at which the aircraft is going fast enough to make a successful takeoff with one engine out. Bear in mind that a lot of the biggest early jets had four engines, none of which was nearly as powerful as the current generation (some actually used water injection systems to boost their thrust during takeoff), and which suffered failures a lot more often.

“Rejected takeoffs” are pretty rare occurrences these days, and airport design has gotten better at minimizing the consequences of an aircraft running off the end of a runway if circumstances conspire to make things exciting for its inhabitants. For example, "engineered material arresting systems” are basically long slabs of pavement designed to collapse under the weight of an aircraft, grabbing hold of it and bringing it to a fairly enthusiastic stop.

This may not sound desirable, but some of the places EMAS has been installed (including Boston’s Logan and New York’s LaGuardia Airports) have seen more than their share of aircraft in trouble winding up in bodies of water during what are euphemistically (but accurately) referred to as “runway excursions.”

Such departures can happen either during takeoff or landing emergencies, and it’s nice to know that the chances of surviving both have been improved significantly with one ingenious invention.

This post originally appeared on Quora. Click here to view.

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Big Questions
Why Does Turkey Make You Tired?
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Why do people have such a hard time staying awake after Thanksgiving dinner? Most people blame tryptophan, but that's not really the main culprit. And what is tryptophan, anyway?

Tryptophan is an amino acid that the body uses in the processes of making vitamin B3 and serotonin, a neurotransmitter that helps regulate sleep. It can't be produced by our bodies, so we need to get it through our diet. From which foods, exactly? Turkey, of course, but also other meats, chocolate, bananas, mangoes, dairy products, eggs, chickpeas, peanuts, and a slew of other foods. Some of these foods, like cheddar cheese, have more tryptophan per gram than turkey. Tryptophan doesn't have much of an impact unless it's taken on an empty stomach and in an amount larger than what we're getting from our drumstick. So why does turkey get the rap as a one-way ticket to a nap?

The urge to snooze is more the fault of the average Thanksgiving meal and all the food and booze that go with it. Here are a few things that play into the nap factor:

Fats: That turkey skin is delicious, but fats take a lot of energy to digest, so the body redirects blood to the digestive system. Reduced blood flow in the rest of the body means reduced energy.

Alcohol: What Homer Simpson called the cause of—and solution to—all of life's problems is also a central nervous system depressant.

Overeating: Same deal as fats. It takes a lot of energy to digest a big feast (the average Thanksgiving meal contains 3000 calories and 229 grams of fat), so blood is sent to the digestive process system, leaving the brain a little tired.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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Big Questions
How Are Balloons Chosen for the Macy's Thanksgiving Day Parade?
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The balloons for this year's Macy’s Thanksgiving Day Parade range from the classics like Charlie Brown to more modern characters who have debuted in the past few years, including The Elf On The Shelf. New to the parade this year are Olaf from Disney's Frozen and Chase from Paw Patrol. But how does the retail giant choose which characters will appear in the lineup?

Balloon characters are chosen in different ways. For example, in 2011, Macy’s requested B. Boy after parade organizers saw the Tim Burton retrospective at the Museum of Modern Art. (The company had been adding a series of art balloons to the parade lineup since 2005, which it called the Blue Sky Gallery.) When it comes to commercial balloons, though, it appears to be all about the Benjamins.

First-time balloons cost at least $190,000—this covers admission into the parade and the cost of balloon construction. After the initial year, companies can expect to pay Macy’s about $90,000 to get a character into the parade lineup. If you consider that the balloons are out for only an hour or so, that’s about $1500 a minute.

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