2678: Wing Lift

2022-09-30T11:57:07Z

CorrectHorseBatteryStaple:

{{comic
| number = 2678
| date = September 28, 2022
| title = Wing Lift
| image = wing_lift_2x.png
| imagesize = 679x358px
| noexpand = true
| titletext = Once the air from the top passes below the plane of the wing and catches sight of the spooky skulls, it panics, which is the cause of turbulent vortices.
}}

==Explanation==
{{incomplete|Created by a SPOOKED OUT BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic is a parody of the often erroneous explanations given to physics students on how wings produce lift.

Specifically, it parodies the Equal Transit Time fallacy, which states that the air flowing above the wing and the air flowing below the wing have to travel from one side of the wing to the other in equal time, so the air above the wing has to travel faster to keep up with the air below. This assumes that the air above the wing is somehow conscious of what the air below the wing is doing.

This assumption of consciousness is taken to extreme parody by the comic - it implies that the bottom air can be frightened by skulls, that the top air is curious to see what's going on, and that air can panic.

***

Wings can produce {{w|Lift (force)|lift}},<ref name="Prandtl & Tietjens (1952)">Tietjens, Oskar Karl Gustav; [https://en.wikipedia.org/wiki/Ludwig_Prandtl Prandtl, Ludwig] (1957). [https://books.google.com/books?id=4KtFcuCZ3VsC&pg=PR1 ''Fundamentals of Hydro- and Aeromechanics'']. Courier Corporation. ISBN 978-0-486-60374-2</ref> i.e. an upwards force with which an aircraft is held in the air.

Three reasons are often given as to why airplane wings produce lift:
* {{w|Bernoulli's principle}} (which is the most frequently cited)
* The airplane wing is angled up at the front so that air hits the bottom and is pushed downwards (The ski effect or {{w|Newton's sine-square law of air resistance}}).
* {{w|Coandă effect}} (The top is curved, so air going over the wing must curve downwards in order to avoid creating a vacuum above the back of the wing, and by Newton's third law, this results in an upwards force on the wing.)
The comic references all three of these reasons. Airflow splitting references Bernoulli's principle, while the air at the bottom being scared and fleeing downwards is similar to the actual effect, which is caused by air hitting the angled bottom of the wing. The air going over the top curving down references the Coandă effect, although the comic claims that this effect is instead caused by the top-air noticing the bottom-air fleeing downward and goes down to investigate why the bottom-air is fleeing. The mention of Newton's third law is indeed correct, even if the movement of the air is for the wrong reasons. In the title text, it additionally suggests that the top-flow also end up glimpsing the printed skulls, causing it to also chaotically flee, generating a wing's classic turbulent wake.

Randall previously dealt with explanations of wing lift in [[803: Airfoil]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[Caption at the top of the panel:] How a wing produces lift

[A diagram of the cross-section of a plane wing. It is large and rounded on the left end and flat on the bottom while the top curves down to meet it at a sharp point. There are many small arrows indicating the flow of wind, as well as captions.]

[The arrows come from the left of the panel, point towards the wing, and then half begin to go over and half begin to go under. A caption in the middle of this flow reads:] Airflow splits around the top and bottom of the wing

[A circle underneath the diagram is connected to an arrow which points to the underside of the wing. A repeating pattern of small black (simplified) skulls fills the circle and arrow. The caption to the right of this is:] Spooky skulls microprinted on the bottom of the wing frighten the air, which flees away downward

[The arrows begin to curve downwards after this caption, and are joined by the top arrows which have also begun to curve downward. In these arrows is a caption:] Top air goes to see what's wrong

[Both streams of arrows have joined and are pointing to the bottom right of the panel. In front of them is a caption:] By Newton's third law, downward deflection of air pushes wing upward

{{comic discussion}}

[[category:Engineering]]
[[category:Physics]]
[[category:Aviation]]

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2678: Wing Lift