1. Mick West

    Mick West Administrator Staff Member

    Source: https://www.youtube.com/watch?v=icLNtF_ehwo

    When I sat in the exit row of a plane from Sacramento to Denver. I saw what looked like a glitch in the matrix. A weird spike in the fabric of reality! Turns out it was refraction, the high-pressure shockwave over the wing was acting as a lens and distorting a bit of the image, as well as projecting sunlight in a streak on the wing.

    They got quite interesting at times, sometimes with multiple refraction spikes
    Metabunk 2019-10-21 15-40-13.

    (The second leg was from Denver to New York)
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  2. Mick West

    Mick West Administrator Staff Member

    The refraction is really interesting. It looks like the image is being raised up into a spike.
    Metabunk 2019-10-21 17-49-09.
    But it's not, it's mostly just being shifted forward (towards the front of the plane). This means the light is bend towards the back of the plane, which makes sense as light is bent towards high pressure (high density)

    I'm curious about what role this shock wave has in the formation of aerodynamic contrails.

    Also there's this thread:

    Source: https://www.youtube.com/watch?v=j4JHVEig2Tw
    Last edited: Oct 21, 2019
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  3. Mechanik

    Mechanik Member

    Thanks, Mick. Fascinating. More than once, I’ve thought I saw odd, momentary glitches along the edges of the winglets, but my vision is so poor that I dismissed them as artifacts of my own perception. I’m going to have to look more closely next time.
  4. Fin

    Fin Member

    Wow! What a wonderful catch. Nice one, Mick.
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  5. Mick West

    Mick West Administrator Staff Member

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  6. Mick West

    Mick West Administrator Staff Member

  7. Mick West

    Mick West Administrator Staff Member

    Some details of my flights, on October 16, 2019

    I first noticed it at 9:44 AM PDT (16:44 UTC) on flight UA2285 (an Airbus A319) from Sacramento to Denver. The last video on that leg was taken at 9:58. This was at 37,000 and 39,000 feet, and 580 mph (ground speed). I remember seeing on the seat-back screen that we had a quite significant tailwind (maybe 100+ mph). I was sat on the left, so looking north, with the sun behind me.

    Next flight was United 749, a Boeing 757-200, from Denver to Newark, NJ. I was sat on the other side this time, looking South. Images at 3:57 MDT. 37,000 feet, 550 mph ground speed.

    I'd mistakenly thought that both planes were 757s, but it was just the second one. The A319 is a short-bodied plane. but has the same basic cross-section as a 757 (and similar planes like the A320, A321, an B737)

    Attached Files:

  8. Antithesis

    Antithesis New Member

  9. cloudspotter

    cloudspotter Senior Member

    This has popped up on Youtube for me. Seems to show the shadow/projection @Mick West mentions more clearly, this time on a 737

  10. Mick West

    Mick West Administrator Staff Member

    Yeah, YouTube's algorithm seems like it's trying to draw me down a "Transonic shockwave" rabbit hole :)
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  11. Agent K

    Agent K Active Member

    I'm disappointed it's not a glitch in the Matrix. Always wanted to meet Agent Smith.
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  12. Leifer

    Leifer Senior Member

    So....if this exhibits that parts of the plane that are both flying at subsonic and supersonic (transonic)....at the same time.....then.....
    Is part of the plane (aircraft) flying faster than the other parts ?
    Last edited: Oct 26, 2019
  13. Spectrar Ghost

    Spectrar Ghost Senior Member

    I mean, obviously not, because it’s not falling apart. Remember that one of the sources of lift on aircraft is the Bernoulli effect, where faster moving air has lower air pressure. To employ this, air moving over the top of an airfoil has further to travel than air moving over the bottom. Even if this is only a 10% difference, there exists a flight regime where the air on top of the wing is moving supersonically, and that under moves subsonically.

    More specifically, this type of recompression shock appears to be what is being viewed.
    Last edited: Oct 26, 2019
  14. TWCobra

    TWCobra Senior Member

    Critical Mach number is the mach number where some part of the airflow over an aircraft is moving at Mach 1 or greater. It happens more than you think, particularly when an aircraft is flying a bit faster than normal, usually trying to catch up on schedule. (were any of these flights running late, Mick?)
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  15. Mick West

    Mick West Administrator Staff Member

    The second flight was a couple of hours late.
  16. some_guy

    some_guy New Member

    One of my profs in undergrad told us about this, I've never been lucky enough to see it myself though. Great pics & video.