Why Do Planes Climb So Steeply at Takeoff?

iStock
iStock

Ron Wagner:

I’m going to guess that you mean commercial airliners on which you ride “go so steep.” Obviously, you feel they go steep, but “steep” is a relative term—one person’s “steep” is another person’s “boring.”

I’LL SHOW YOU “STEEP”

I had the good fortune to get taxpayer-funded pilot training through the U. S. Air Force, which included flying the Northrop T-38 Talon supersonic jet. When it was first introduced, it was the fastest-climbing aircraft in the world and set the world time-to-climb record.

The specific jet they used to set that record had the tail number of 10849. After that record-setting flight, 849 went to the regular training fleet at Webb AFB in Big Spring, Texas, which is where I went to pilot training. The folks at Edwards AFB, where the record was set, painted a list of the various records it had set on the nose, but otherwise, that jet was just a regular member of our fleet at Webb.

Eleven years later, I got to fly 849. Unfortunately, back then there was no such thing as smartphone cameras. If I’d had one, I would have gotten someone to take a pic of that list of records on the nose with me sitting in the cockpit—but, alas!

The records were set in meters, and they ticked off a bunch of them, but the easy one to remember is the climb to 9000 meters because that’s 30,000 feet.

The climb record must be measured from the moment the aircraft first moves on the runway, all the way through takeoff, gear up, and then start climbing. That whole process—from dead-stop on the runway to 30,00 feet—took 62 seconds ... and here’s a photo taken that day, like a scalded angel trying to get back to heaven.

A plane takes off at a steep incline
Quora

Now that’s what I call a “steep” takeoff.

Airliners do not take off “steep.”

BUT AIRLINERS DON’T HANG AROUND AT LOW ALTITUDE

Jet aircraft are most efficient at high altitudes. The most fuel efficient profile any jet can fly on a cross-country trip would be to climb at its maximum rate all the way to cruising altitude, level off and pull back to cruise power, and stay there until the precise moment the engines can be pulled to idle and descend to a landing.

Due to traffic and passenger comfort, the airliners don’t fly that maximum efficiency profile, but they try to get close.

And that’s why it seems to you that jet airliners climb “relatively steep,” but trust me, they do not fly steep. That T-38 climbed steep!

JUST FOR THE RECORD

A few years later, the F-4 broke the T-38′s record. I haven’t followed the latest, but I clearly recall in 1975 when the F-15 brought the 9000 meter record down to 48.8 seconds.

I just watched a video of an airliner takeoff and saw that it broke ground at about 50 seconds after brake release and they raised the gear at about one minute after brake release.

And so, to simplify this: From brake release, the F-15 can be at 30,000 in the time that a typical airliner is just raising its nose on the runway. Forty. Eight. Point. Eight. Seconds.

The F-15 has a thrust-to-weight ratio of greater than one, which means it can accelerate going perfectly vertical, like a ballistic rocket.

Now that, my friends, is the ultimate in “steep.”

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

Where Did the Term Brownie Points Come From?

bhofack2/iStock via Getty Images
bhofack2/iStock via Getty Images

In a Los Angeles Times column published on March 15, 1951, writer Marvin Miles observed a peculiar phrase spreading throughout his circle of friends and the social scene at large. While standing in an elevator, he overheard the man next to him lamenting “lost brownie points.” Later, in a bar, a friend of Miles's who had stayed out too late said he would never “catch up” on his brownie points.

Miles was perplexed. “What esoteric cult was this that immersed men in pixie mathematics?” he wrote. It was, his colleagues explained, a way of keeping “score” with their spouses, of tallying the goodwill they had accrued with the “little woman.”

Over the decades, the phrase brownie points has become synonymous with currying favor, often with authority figures such as teachers or employers. So where exactly did the term come from, and what happens when you “earn” them?

The most pervasive explanation is that the phrase originated with the Brownies, a subsect of the Girl Scouts who were encouraged to perform good deeds in their communities. The Brownies were often too young to be official Girl Scouts and were sometimes the siblings of older members. Originally called Rosebuds in the UK, they were renamed Brownies when the first troops were being organized in 1916. Sir Robert Baden-Powell, who had formed the Boy Scouts and was asked to name this new Girl Scout division, dubbed them Brownies after the magical creatures of Scottish folklore that materialized to selflessly help with household chores.

But the Brownies are not the only potential source. In the 1930s, kids who signed up to deliver magazines like The Saturday Evening Post and Ladies' Home Journal from Curtis Publishing were eligible for vouchers labeled greenies and brownies that they could redeem for merchandise. They were not explicitly dubbed brownie points, but it’s not hard to imagine kids applying a points system to the brownies they earned.

The term could also have been the result of wartime rationing in the 1940s, where red and brown ration points could be redeemed for meats.

The phrase didn’t really seem to pick up steam until Miles's column was published. In this context, the married men speaking to Miles believed brownie points could be collected by husbands who remembered birthdays and anniversaries, stopped to pick up the dry cleaning, mailed letters, and didn’t spend long nights in pubs speaking to newspaper columnists. The goal, these husbands explained, was never to get ahead; they merely wanted to be considered somewhat respectable in the eyes of their wives.

Later, possibly as a result of its usage in print, grade school students took the phrase to mean an unnecessary devotion to teachers in order to win them over. At a family and faculty meeting at Leon High in Tallahassee, Florida, in 1956, earning brownie points was said to be a serious problem. Also called apple polishing, it prompted other students in class to shame their peers for being friendly to teachers. As a result, some were “reluctant to be civil” for fear they would be harassed for sucking up.

In the decades since that time, the idiom has become attached to any act where goodwill can be expected in return, particularly if it’s from someone in a position to reward the act with good grades or a promotion. As for Miles: the columnist declared his understanding of brownie points came only after a long night of investigation. Arriving home late, he said, rendered him “pointless.”

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

Grocery Stores vs. Supermarkets: What’s the Difference?

gpointstudio/iStock via Getty Images
gpointstudio/iStock via Getty Images

These days, people across the country are constantly engaging in regional term debates like soda versus pop and fireflies versus lightning bugs. Since these inconsistencies are so common, you might have thought the only difference between a grocery store and a supermarket was whether the person who mentioned one was from Ohio or Texas. In reality, there are distinctions between the stores themselves.

To start, grocery stores have been around for much longer than supermarkets. Back when every town had a bakery, a butcher shop, a greengrocery, and more, the grocery store offered townspeople an efficient shopping experience with myriad food products in one place. John Stranger, vice president group supervisor of the food-related creative agency EvansHardy+Young, explained to Reader’s Digest that the grocer would usually collect the goods for the patron, too. This process might sound familiar if you’ve watched old films or television shows, in which characters often just hand over their shopping lists to the person behind the counter. While our grocery store runs may not be quite so personal today, the contents of grocery stores remain relatively similar: Food, drinks, and some household products.

Supermarkets, on the other hand, have taken the idea of a one-stop shop to another level, carrying a much more expansive array of foodstuffs as well as home goods, clothing, baby products, and even appliances. This is where it gets a little tricky—because supermarkets carry many of the same products as superstores, the next biggest fish in the food store chain, which are also sometimes referred to as hypermarkets.

According to The Houston Chronicle, supermarkets and superstores both order inventory in bulk and usually belong to large chains, whereas grocery stores order products on an as-needed basis and are often independently owned. Superstores, however, are significantly larger than either grocery stores or supermarkets, and they typically look more like warehouses. It’s not an exact science, and some people might have conflicting opinions about how to categorize specific stores. For example, Walmart has a line of Walmart Neighborhood Markets, which its website describes as “smaller-footprint option[s] for communities in need of a pharmacy, affordable groceries, and merchandise.” They’re not independently owned, but they do sound like grocery stores, especially compared to Walmart’s everything-under-the-sun superstore model.

Knowing the correct store terms might not always matter in casual conversation, but it could affect your credit card rewards earnings. American Express, for example, offers additional rewards on supermarket purchases, and it has a specific list of stores that qualify as supermarkets, including Gristedes, Shoprite, Stop & Shop, and Whole Foods. Target and Walmart, on the other hand, are both considered superstores, so you won’t earn bonuses on those purchases.

And, since grocery shopping at any type of store can sometimes seem like a competitive sport, here’s the ideal time to go.

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

SECTIONS

arrow
LIVE SMARTER