What Do Pilots Use to Detect Turbulence?

iStock.com/Maravic
iStock.com/Maravic

by Joe Shelton

I think the concept of "turbulence" has gotten a bad reputation.

Just like the wind, turbulence isn't an on or off thing; it's a spectrum.

Step outside one day and a light breeze might be hard to feel, while the next day you might have trouble holding onto your hat because the wind is so strong. But most of the time it's somewhere in between those extremes.

Turbulence is exactly the same. Some days, some places, nothing. Some days it can rattle your teeth (or turn your stomach). But most of the time when turbulence exists, it is light or at worst case slightly annoying.

How do pilots detect turbulence?

Weather forecasts provide estimates when there might be turbulence. The thing to remember is the noun forecast: It's not a guarantee that it will be turbulent, nor is the lack of mention of turbulence in a forecast a guarantee that there won't be turbulence.

In addition, turbulence can be widespread as well as very localized.

I typically detect or expect serious or widespread turbulence as well as local turbulence in one of three of ways:

  • Cumulus clouds: If the clouds are tall and vertical and/or getting taller, then there is a good chance there is turbulence around. The taller the clouds and the faster they are growing, the worse the probable turbulence. Especially in the clouds. The worst example of that would be a thunderstorm. The turbulence within a thunderstorm can tear an aircraft apart.
  • Hot days: Also known as convection, warm and especially hot days mean that the hot air is rising and the reciprocal, cold air is descending. That's a recipe for turbulence. Depending upon the temperature and the aircraft's altitude the turbulence can be irritating or it can be very uncomfortable.
  • Wind: Wind can "tumble," especially downwind of mountains—often for many miles downwind—and it can even be turbulent over mountains, as winds are encouraged to rise following the upwind mountain side.

With very few exceptions, for the most part turbulence isn't dangerous. At least to aircraft. Pilots know how to manage turbulence, often simply by slowing the aircraft's airspeed and/or changing altitude.

However, clear-air turbulence (CAT)—severe turbulence that happens in what otherwise seems to be calm, clear air—can cause injuries to passengers who aren't wearing seat belts or, worse, are walking. And CAT is very difficult to detect until you experience it.

(By the way, clear-air turbulence got its name because although turbulence is often accompanied by clouds, this particular form isn't. Hence the name.)

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

Why Do We Eat Pumpkin Pie at Thanksgiving?

gjohnstonphoto/iStock via Getty Images
gjohnstonphoto/iStock via Getty Images

While it’s possible—even probable—that pumpkins were served at the 1621 harvest festival that’s now considered the predecessor to Thanksgiving, attendees definitely didn’t dine on pumpkin pie (there was no butter or wheat flour to make crust).

The earliest known recipes for pumpkin pie actually come from 17th-century Europe. Pumpkins, like potatoes and tomatoes, were first introduced to Europe in the Columbian Exchange, but Europeans were more comfortable cooking with pumpkins because they were similar to their native gourds.

By the 18th century, however, Europeans on the whole lost interest in pumpkin pie. According to HowStuffWorks, Europeans began to prefer apple, pear, and quince pies, which they perceived as more sophisticated. But at the same time pumpkin pie was losing favor in Europe, it was gaining true staple status in America.

In 1796, Amelia Simmons published American Cookery, the first cookbook written and published in the New World colonies. Simmons included two recipes for “pompkin pudding” cooked in pastry crust. Simmons’s recipes call for “stewed and strained” pumpkin, combined with a mixture of nutmeg, allspice, and ginger (yes, it seems our pumpkin spice obsession dates back to at least the 1500s).

But how did pumpkin pie become so irrevocably tied with the Thanksgiving holiday? That has everything to do with Sarah Josepha Hale, a New Hampshire-born writer and editor who is often called the “Godmother of Thanksgiving.” In her 1827 abolitionist novel Northwood, Hale described a Thanksgiving meal complete with “fried chicken floating in gravy,” broiled ham, wheat bread, cranberry sauce, and—of course—pumpkin pie. For more than 30 years, Hale advocated for Thanksgiving to become a national holiday, writing regular editorials and sending letters to five American presidents. Thanksgiving was a symbol for unity in an increasingly divided country, she argued [PDF].

Abraham Lincoln eventually declared Thanksgiving a national holiday in 1863 (to near-immediate outcry from Southerners, who viewed the holiday as an attempt to enforce Yankee values). Southern governors reluctantly complied with the presidential proclamation, but cooks in the South developed their own unique regional traditions. In the South, sweet potato pie quickly became more popular than New England’s pumpkin pie (mostly because sweet potatoes were easier to come by than pumpkins). Now, pumpkin pie reigns supreme as the most popular holiday pie across most of the United States, although the Northeast prefers apple and the South is split between apple and pecan, another Southern staple.

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What's the Difference Between Stuffing and Dressing?

iStock
iStock

For carbohydrate lovers, nothing completes a Thanksgiving meal quite like stuffing—shovelfuls of bread, celery, mushrooms, and other ingredients that complement all of that turkey protein.

Some people don’t say stuffing, though. They say dressing. In these calamitous times, knowing how to properly refer to the giant glob of insulin-spiking bread seems necessary. So what's the difference?

Let’s dismiss one theory off the bat: Dressing and stuffing do not correlate with how the side dish is prepared. A turkey can be stuffed with dressing, and stuffing can be served in a casserole dish. Whether it’s ever seen the inside of a bird is irrelevant, and anyone who tells you otherwise is wrong and should be met with suspicion, if not outright derision.

The terms are actually separated due to regional dialects. Dressing seems to be the favored descriptor for southern states like Mississippi, Tennessee, South Carolina, and Georgia, while stuffing is preferred by Maine, New York, and other northern areas. (Some parts of Pennsylvania call it filling, which is a bit too on the nose, but to each their own.)

If stuffing stemmed from the common practice of filling a turkey with carbs, why the division? According to HuffPost, it may have been because Southerners considered the word stuffing impolite, and therefore never embraced it.

While you should experience no material difference in asking for stuffing or dressing, when visiting relatives it might be helpful to keep to their regionally-preferred word to avoid confusion. Enjoy stuffing yourselves.

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