"Wendover Productions has entered the chat"

As an Aerospace Engineer and fluid dynamicist I had super low hopes for the explanations SciShow would give for induced drag, but all I can say is "bravo, Sci-Show, bravo!" Well done here. I wish you mentioned the awesome engineer who helped invent Winglets, Richard Whitcomb. A super amazing Aerospace engineer working for NASA who never deposited his paychecks.

Children were folding winglets into paper airplane designs in the 1960's to get more distance.

I work as a professional pilot and I had no idea I was categorized as a radiation worker. Wtf.

Hank: I am sorry you live in Phoenix. *Phoenix will remember that*

Scishow, Joe Scott, and Veritasium needs WAAAAAYY more love from the algorithm.

Today's episode, bought to you by Wendover Productions

February: "Tens of thousands of aeroplanes fly around the world every day" April "Bahahahaa! Lol that is funny!"

Me: Ooo a 25min scishow! Hank: Compliation Me: I have seen every scishow since the beginning! *skip*

The discussion of hypersonics had sufficient caveats and details to satisfy me. This is the area of my PhD research. My biggest pet-peev is the definition of hypersonic as anything above Mach 5, but you guys did a decent job adding a caveat and talking about how it's really about temperature. The metric that determines whether or not something becomes hypersonic is whether or not the air (or other working gas, say if you're on a different planet, like Mars) gets so hot that the gas molecules start to get excited in ways that they normally don't at lower temperatures (i.e., vibrational excitation and possibly electronic excitation) or start to chemically react or break down. The important metric for this is called "Total Temperature" AKA "Stagnation Temperature". This quantity is derived from the energy equation and is really just a different way of expressing the total enthalpy of the flow. Total enthalpy is the internal energy (temperature) plus the gas' stored ability to do work (pressure, basically) plus the kinetic energy. This total enthalpy is a conserved quantity so if the kinetic energy goes to zero and you extract as much pressure work as you can from the gas, you'll be left with only internal energy (heat causing a temperature rise). And this temperature determines whether the air/gas molecules start behaving in a way where their internal energy is no longer stored in just rotation and translation (bouncing off other gas molecules) but may also include the length of the chemical bonds vibrating or knocking electrons into higher energy orbitals or even causing molecules like N2 and O2 to dissociate and undergo other chemical reactions. The total temperature or stagnation temperature describes how hot the flow is capable of getting. And if it can get hot enough to cause these other modes of internal energy to become important or dissociation, then the flow is hypersonic. It is completely possible to create Mach 10 (or higher) flows in a lab that are *NOT* hypersonic if the total temperature is less than ~ 500 degrees C. But for atmospheric flight, hypersonic conditions do tend to start at around Mach 5 because the total temperature is a function of the static temperature (how warm the air outside is) and the kinetic energy caused by the speed of the vehicle. In a lab, when you accelerate the flow the static temperature drops because you've converted the stored energy (total enthalpy) into kinetic energy. This comment is way to looooong but I started typing and couldn't stop myself. I have other things I should be doing instead of this, so I'm not going to bother proofing it or correcting minor errors, which I'm sure there are plenty of.

22:04 "Even though other types of electric vehicles are taking off- haha." Me, 3 seconds later: HAHA.

I've lived almost my entire life in the NYC metropolitan area. Back when the Concorde was still flying, I often found myself on the highway driving past JFK airport on Sunday mornings, around the time when the Concorde would be taking off for Paris. When they shoved the throttles forward into maximum takeoff power, they created an indescribable blowtorch roar that seemed to fill the entire sky from horizon to horizon - sound like godzown Bernz-O-Matic. And occasionally I'd be in the right place at the right time to hear the sonic boom as the Concorde went overhead; it wasn't really all that traumatic, just a fast double thud that was over before you understood what it was. Now we have planes that allow a passenger to TAKE A SHOWER during the flight! That just blows my mind!

This video was just plane interesting!

“The airline is trying to move 162 people from Minneapolis to Orlando as quickly and safely as possible” - nope, not quite accurate, they’re trying to move passengers safely and as quickly as profitable

Aaayyy im in school to be an aviation mechanic, so I'm super stoked to see how much of this i already know

*WENDOVER PRODUCTIONS WANTS TO KNOW YOUR LOCATION*

An airplane video that isn't Wendover Productions? What's happening.

Oh man, I hate when there's too much drag on a plane. All that hairspray choking up the cabin ... someone always breaks a nail trying to open those little bags of peanuts ... and don't get me started on all the sequins.

"If you live in Phoenix, I'm sorry" You and me both, bro.

I love the Engineering Explained shirt. Jason is awesome. Love this show and his. Anything that keeps me interested and learning is what I love.

You need more Micheal Aranda,Hank! Guys got the voice of an angel, even though we all enjoy how excited you get when something cool happens in the Physics world haha

I lived in Phoenix when that happened... in a car with no A/C. Also the pavement softens which doesn't matters either.

One man shouts across a room to his friend, "Hey! Air is incompressable!" But his friend never heard him.

I trust SciShow not to do this maliciously, but not labeling a compilation episode as such is a bit misleading.

18:30 Can confirm. There was one time (mid- to late 1990s) when a plane went supersonic over my town (north Texas, so quite a bit inland) and the resulting sonic boom caused everything in our living room to jump a few inches. Nobody was quite sure what happened, but I would assume that the pilot flying that plane at least got his license suspended. This only happened once, so I guess the lesson was learned. We did have an Air Force base in the area, but I'm pretty sure the place had been decommissioned by that point so I think the culprit was flying to or from the local airport.

Loving these types of episodes. Keep being awesome.

@2:54 I've been told (by aircraft maintenance people) it's more about room to maneuver on the ground at airports than structure. Winglets add the same weight penalty as extending the wingspan. You don't have to add structure to hold a wing up. The structure is there to hold the fuselage up.

0:29 Even more incredible is that one of those tubes of metal, the Boeing 737, weighs over 60 tons ON ITS OWN (so no fuel, and no payload)

“Air, which is a fluid” Sir? Sir?! I guess I was edumacated

21:40 _Then_ the X-43 launches a tiny Y-97 out of its nose cone's rail-gun.

Hank: if you're an airline the thing you hate the most about flying is drag Ru paul: exuuuuse me honey!!??

And today on Scishow: Hank likes squared shirts

Very interesting and fluid transitions between topics. Simply excellent

Terrific video Hank & company. I always learn something from watching one of your videos. Keep up the good work.............. 👍👍✈✈✈✈👍👍

This episode was amazing. Thanks guys.

Loved this video, never realised how (relatively) recent the discovery of incompressibility was!

Great work hank and crew, that was really interesting, informative, intertaining (mis spelled INtentionally lol) and funny as usual. 😀 p.s. i was in phoenix that day, and it was HOT! 123 yuck.

Love the longer format

Kindly mention in the title when these are rehashes of old episodes. I love your program, but I don't need to see it twice.

1:33 this is actually wrong. Drag is the component of that total that points in the direction opposit to the movement of the object. So drag is only the part responsable for slowing you down. The rest is lift

Love these compilations. Learn some things while painting cabinets

Now I don't have to worry about something I didn't worry about until now. Literally how I feel watching this channel 😂

4:19 reminds me of something funny: when i was going through radiation treatment for cancer (i got better) i had to carry around a special card saying _why_ I was radioactive and was advised against flying anywhere or going to major government buildings since i could set off their gieger counters. That radiologist clinic even had a couple patients get temporarily detained at an airport because the TSA got alerted when someone radioactive tried boarding a flight.

This is, by far, my favorite channel. I always learn something new. Thank you for all the hard work and research you do in producing these videos!

Thank you! I've been flying a lot lately and usually fly right arouns the wing, and have been super curious about those flappy wing things.

Pretty interesting stuff for sure. I was wondering about those supersonic passenger planes and what happened to them. How they work and all of that jazz :)

25min episode ?! YES PLEASE MORE

I love aeroplanes ! I'm currently a student pilot in Canada. Thank you Sci-show

I want to make a joke about planes, but the joke would fly over your head.

I enjoyed this compilation.

Winglets can also be a tasty poultry based treat. When I hear the phrase "Mach 5", I immediately think of Speed Racer.

Seems they are out of ideas because they just winged it with this video.

The creators of Nebula: Is he one of us??? 🤔

Dude that Engineering Explained shirt is awesome!

Hank have you ever thought you need to go camping and do some bush crafting to get away from all the stress?

Excellent!

By the mid 70s we were flying R/C gliders with curved wingtips. It didn't seem to matter if they were curved up or down. But they were flying at very low speeds. Still the tips helped. I built one and left the tips off for a set of flights before putting them on. Was able to 10-20% longer flight times with them on.

The Valley gets hot, I remember 123f when I landed there from St. Louis, left there at about 49f. Also, air is stated as being a fluid and gas interchangeably throughout this video.

RE: Airline staff exposure to Cosmic Rays - I used to work for a research institution that maintained a network of ground-based neutron detectors designed to monitor the after effects of cosmic rays hitting the earth. By seeing how the influx of cosmic rays changed over time they were able to study the solar winds. But related to this topic, the Air Force was one of the recipients of our data so they could calculate the exposure rates of their pilots and flight crew based on an empirical measurement of cosmic rays every hour.

Currently a freshman in aerospace engineering , loved this video and you are awesome as always 👍🏼

There was an experiment done at Adelaide airport which might help with that heat issue, they watered the ground at night and found that that watering kept the air temp down which had the added benefit being that planes could take off even in hotter temps

That's super, man!

6 MILLON Subscribers!

Planes. Submarines with wings.

This is just plane awesome!

Yaa I have read about it. Winglets basically (hypothetically) increases the wingspan infinitely. Mind blowing 😄

Wow 101 years before I was born the Wright Brothers first airplane flew, that's pretty cool

(00:20) Flying "tubes of metal" sounds like a mash-up of the definitions for snakes ("muscle tubes") and planes ("metal snakes with wings"). Some similar snake similes: Trains - "metal snakes on tracks", Submarines - "sea snakes with props", Bobsleds - "snakes on skates" and finally, although currently in the realm of science fiction, Teleportation has been dubbed "the snake-less transportation of tomorrow."

19:14 “but maybe that’s not enough, maybe you want to go faster. The Concorde ii would be very close to going beyond supersonic and into an even faster category,” Lightspeed.

Hello from the surface of the su..... Phoenix!

Hey I live in Mpls and I would love to fly to Florida! Avoid tomorrow's deep freeze ;)

Awesome

My friend: Hey wanna go eat Pizza? Random kid names Pizza: **cries**

I thought to get to Hypersonic you had to use the Super Emeralds.

I’m watching this as my best friend is on a plane!

Like before even watching. That’s a Scishow fan.

Hey SciShow! This is GOD lovin Merica and we don’t use no mamby-pamby metric system.

This better not be a compilation. Damn it!

About energy density... practicality might be an issue but hydrogen has about 3 times the amount of energy per kg that jet fuel has.

i don't think there's anything "normal" about airplanes. actually i wonder how people can just go and watch a video on a tiny screen when something so amazing is happening. i've flown a lot already but every time it amazes me. not only the plane itself, but the world outside of the window. i just cannot take my eyes off. and i keep measuring all kinds of stuff with the sensors in my cellphone

Shivkar Bāpuji Talpade was an Indian scholar who is said to have constructed the first unmanned airplane in 1895 (before Wright brothers). Talpade lived in Mumbai and studied Sanskrit literature and the Vedas.

"Winglets? that's like, your opinion, man" Boeing 777, 787 and 747-8 with their raked wingtips

Surprised You Haven't Mentioned Aliens etc. ! Nice One plus Cheers

One annoying misconception ( at least partial) is that myth that Wright's flyer went 10 mph on its first flight. It's not completely wrong but it gives that notion that it could go super slow . The thing is the flyer was going around 40mph or 70 km/h to lift off. They just chose a day for the first flight with ideal conditions (quiet common with worlds first) . They flew into 30mph headwind which gave them ground speed of several mph but actual air speed of 40. They also picked (I heard this was actual lucky chance rather than conscious decision) a day with extremely high air pressure and low temperatures which both increased lift and power of their engine. That's actually why centennial reenaction failed to get off the ground . They simply didn't have the ideal conditions. That of course gave birth to conspiracy theories that the actual flier was a hoax.

Currently in Phoenix enjoying the sunny 72° weather in January

The hypersonic planes sound like they'd need three sets of engines, one for each level of sonic (sub, super, and hyper) with at least two of the sets being on top of the wings. All three, as well as the body of the plane being either made of or coated in titanium. Obviously there is a lot more to it, and I'm sure every aerospace engineer has thought of this before me. But it seems like a good base at least.

An aircraft compilation is just plane cool.

Nice compilation 👍✈️ps I'm an aircraft engineer and found it a fun subject if a little in layman's terms for me 😎

hi, Concorde wasn't that noisy. In fact, we loved it as primary school students, see the supersonic bang was at 11:15AM, indicating that there were only 15 min left before lunch hour (ok, two hours, we are in France aftet all, we have a reputation to defend! 😜). cheers

"It's a BIRDPLAAANEEE, a motherf*ckin' birplane!" - ladies and gentlemen, the Axis of Awesome

23:20 Jet fuel is very energy dense, but it would have been good to point out that about 50% of the energy in that fuel gets wasted due to thermal inefficiencies. Internal combustion engines are even worse, two thirds of the energy in gasoline is wasted right out the tailpipe as heat. Electric motors on the other hand can be more than 95% efficient at converting the energy into motion. Electric energy storage still has a long way to go, but not quite as far as the video makes it seem.

Hey scishow, I should probs be able to tell from the length but id love if y'all marked your compalation vids in the title

I'm more than a bird, I'm more than a plane, I'm a bird plane, a mother****ing bird plane. (Credit to Axis of Awesome)

Most modern day aeroplanes actually don't have winglets; these are mainly found on airliners and cargo planes.

Awesome video! Do helicopters now! ; )

I work right next to an airport and was having exactly the thoughts of "how strange are planes" all day. Coincidence I think so

Not that it makes any difference to the point you were making about the noise problems associated with supersonic flight, but New York to London was not the only route the Concorde flew. I know from personal experience they also flew from D.C. to London, and I think there were other such routes that were almost totally over water at the end points.

I am getting on a plane to Phoenix in like 6 hours for a doctoral interview. If I get in I will be living there Hank! Don't dash my dreams of living in Phoenix before it even happens! How rude lmao

I’m amazed that an incredible feat of human ingenuity has become a humdrum, stressful, dull as dishwater form of transportation, when it should be celebrated as an exciting, ingenious way to travel. We take too many things for granted, we really do....

It's a robot. It's a plane. It is both cause it's Lord Starscream.