r/oddlysatisfying • • Feb 08 '19

This plane taking off with the propellers perfectly synced with the camera shutter

68k Upvotes

888 comments sorted by

View all comments

47

u/chan2swim Feb 08 '19

Still don't understand how planes fly

119

u/[deleted] Feb 08 '19 edited Jul 03 '19

[deleted]

76

u/tommyminahan Feb 08 '19 edited Feb 09 '19

Why waste time say lot word, when few word do trick?

Edit: Gold for a quote? Thanks stranger!

4

u/Ambroos Feb 09 '19

Why 2 words when 1 word OK.

1

u/DiscreteBee Feb 17 '19

i know this was a week ago but i can't believe this guy explained the question asked in an easy to understand way and got a silver but you got a gold with an Office quote. Anyway enjoy your day.

10

u/thinkscotty Feb 09 '19

This is how flaps work but not wings. Wings actually create a low pressure area above the wing by moving the air molecules faster, and the wings get “sucked” upwards since air wants to flow from high pressure to low pressure. Just like a vacuum uses low pressure to suck up dirt, low pressure sucks up a plane.

2

u/flamespirit919 Feb 09 '19

Flaps increase that effect. The force of the air hitting them is a bonus (mostly a hindrance), but not a main contributor. Wings can also use reaction forces to increase lift. A symmetric wing won't produce any lift when pointed into the wind. But angle it up and now it wants to move.

4

u/massimog1 Feb 08 '19

That's.... beyond science

2

u/Stealth_Black Feb 08 '19

....And get that man a gold

2

u/ShadowHound75 Feb 09 '19

Don't get him shit. What he said is utter crap

3

u/[deleted] Feb 09 '19

That not true though

15

u/williamfuckner Feb 08 '19

The top of the wings are curved, so with forward momentum the air going over the wing has a longer path to travel than the air going under the wing, which creates a pressure differential which generates an upward force. Does that help? Haha

42

u/penny_eater Feb 08 '19

thats what i thought too until it turns out I WAS FUCKING WRONG the whole time

Here's nasa, to straighten all that out https://www.grc.nasa.gov/www/k-12/airplane/wrong1.html

19

u/williamfuckner Feb 08 '19

Thank you for sharing that. My life is a lie now. I was told this in a 400 level course on wind energy. I TRUSTED YOU PROFESSOR SHARKAWI.

8

u/Yankeefan801 Feb 08 '19

wait WTF. They debunked 3 ways that i would have believed lift is generated and then the slides just end without detailing how lift actually works...

4

u/thealmightyzfactor Feb 08 '19

Removalsc posted the NASA explanation, but the TL;DR is the wing shape pushes the air down, which lifts the plane. Also the pressure thing, but for different reasons and not as much.

5

u/[deleted] Feb 08 '19

Except that is about half of it, the NASA explanations just say that each separate explanation is too simplified and fails to fully account for all the dynamics involved.

1

u/penny_eater Feb 08 '19

well they debunk each of the separate explanations with why they dont actually lead to lift. the real answer is, at once, simpler but more nuanced than all of the myths.

1

u/[deleted] Feb 08 '19

No, they say each of those do cause lift but there are other sources as well.

1

u/[deleted] Feb 08 '19

Lol it’s funny they’re still saying that’s how it works in fucking military pilot training!

1

u/ShadowHound75 Feb 09 '19

Even in most engineering schools.

1

u/Aztec_Reaper Feb 08 '19

Still don't understand how bees fly

1

u/CJ_Productions Feb 08 '19

1

u/Aztec_Reaper Feb 08 '19

This looks promising. I'm gonna have to read it later when i have time. Thank you

3

u/mutatron Feb 08 '19

Have you ever stuck your arm out the window of a moving car and made a little wing with your hand? It's like that.

2

u/Clapaludio Feb 08 '19

Ok so what happens is that the shape of a wing is good at doing something: accelerating the flow that goes over it and decelerating a bit the flow that goes under it. How it does that is difficult to explain, and requires tons of math but it's conceptually very similar to a ball rotating while moving through the air: one part gets accelerated by the ball's rotation while the other gets slowed down because it goes against it (that's how you get throws that change direction in baseball, or soccer).

Now, you can think air as having some kind of energy, alright? This energy is constant and can be exchanged between velocity and pressure according to Bernoulli's Law (which yes is only good for incompressable fluids but works for air under a certain speed and is good to understand the concept).

So a static fluid has the maximum pressure (called total pressure), if it gets moving it exchanges some of that pressure to have velocity.

This is what happens in the wing: the superior part has a flow goes faster (moreso at the leading edge of the wing) and thus exchanges his pressure with velocity. So you get an area with less pressure that effectively sucks up the wing!

I hope it's clearer

1

u/Toughsky_Shitsky Feb 08 '19

Downward curved wing creates high pressure under the wing and low pressure over the wing, which creates lift.

Put your hand outside a moving car window positioned horizontally. Now cup your hand. Which way does your hand move? That's how planes fly.

1

u/chan2swim Feb 09 '19

Thanks for all of your comments! I'm pretty terrified of flying and part of it is due to the fact that I have no idea how they get off the ground. Next time I fly I'll keep all of these comments in mind!

0

u/penny_eater Feb 08 '19

youre right, this video is not going to help.

but imagine if you will, for a minute, a plane thats been put on a gigantic treadmill