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The viral YouTube video, (over 1.1m views at the time of positing), How To Make A Paper Airplane Fly Forever - INFINITY PAPERPLANE purports to show a basic paper plane being flown in continuous circles over a stove, presumably using the updraft of hot air rising to drive the plane to continue.

While I guess the basic idea of using an updraft to keep a glider in the air seems plausible, the video looks hinky to me: The loops are too even, I can't perceive the height changing as it moves in and out of the air above heat source. It looks to me like it is being held up by fishing wire.

Is this a true representation of a cool physics demonstration, or a cheap stunt?

hiergiltdiestfu
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Oddthinking
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1 Answers1

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I call shenanigans.

See how the person folds the flaps to make the plane turn:

I came across this article, with another picture of the plane in mid-flight. The flaps are in the same positions (their red circles in the following picture, not mine):

Quoting the article,

Pilots might be more inclined to buy into the idea if the builder did not proceed to fold the airplane's elevons in a manner that would cause a traditional aircraft to bank to the right.

A NASA article says the same thing, using an actual airplane. The plane will bank and turn on the side with the aileron that is tilted up. This video shows the plane turning in the direction that has the aileron down.

HDE 226868
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    Additionally - and I hesitate to insert this into the answer because I don't have a source for it - the airplane moves away from the burners during its closest approaches to the camera. At that point, only the left wing is being lifted by the updraft, meaning that it should be higher up - which it isn't - which would make the plane turn to the right, which it doesn't. – HDE 226868 Sep 26 '15 at 00:01
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    It's not perfect clear to me, but from the knobs on the stove... are any of those burners actually on? – Dan Bron Sep 26 '15 at 19:54
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    @DanBron it doesn't matter if they are on, they just need to be hot... – Sklivvz Sep 26 '15 at 22:41
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    @Sklivvz Very hot (that plane got some *serious* updrafts), and retain their heat for at least the duration of the demonstration (the plane got some serious updrafts *consistently*; I didn't notice any dampening between the first loop and the last). – Dan Bron Sep 26 '15 at 22:43
  • @DanBron I can't tell. I've seen plenty of stoves (including my home's stove) that have burners going on high but show no visual signs of being on. – HDE 226868 Sep 26 '15 at 23:56
  • However, when the burners are supposedly turned on, they are closer to 1 than to 5, leading me to think that they are hot but no longer on. – HDE 226868 Sep 27 '15 at 00:02
  • @HDE Assuming that the knobs are oriented vertically such that "12 o'clock" is "up" in the photo and "6 o'clock" is "down" (I can't make out the numbers): those bad boys are off. Otherwise there'd be an angle between the knob's gnomon (?) and 12 o'clock. Even at the highest temp you'd expect to see, I dunno, a 12* angle? – Dan Bron Sep 27 '15 at 00:02
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    @DanBron I agreed. – HDE 226868 Sep 27 '15 at 00:03