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So, I flew above the speed of sound today...

  1. abrod520 Aug 5, 2016

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    .... at least according to the in-flight info panel!

    image.jpeg

    Good soundtrack for it too, though I think if our Airbus 321 was actually travelling at 800mph, the vibrations would have been decidedly bad. :eek:

    I wonder if it was tracking ground speed, and our westward flight path + the rotation of the Earth fooled it somehow?
     
    ahartfie, Mad Dog and noelekal like this.
  2. Foo2rama Keeps his worms in a ball instead of a can. Aug 5, 2016

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    Where on the west coast are you moving to? Or maybe just visiting?
     
  3. CanberraOmega Rabbitohs and Whisky Supporter Aug 6, 2016

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    CTS-V, ahartfie, Mad Dog and 5 others like this.
  4. abrod520 Aug 6, 2016

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    Took a job in San Jose, gonna be interesting... Unfortunately moving right after Monterey weekend otherwise I'd have totally been there!
     
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  5. WatchVaultNYC Aug 6, 2016

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  6. Foo2rama Keeps his worms in a ball instead of a can. Aug 6, 2016

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    Good luck with the move. I used to spend a lot of time up there.
     
  7. bronxbomber252 Aug 6, 2016

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    Earths rotation wont impact any aircraft speed indications. There are three basic aircraft speeds:

    Indicated airspeed: basically the pressure difference across the aircraft converted into a speed. This determines aircraft performance such as some speed limits, stall, etc... At sea level, with no wind, this will be close to ground speed. This can also be understood as how many air molecules are passing the aircraft per amount of time.

    True air speed: this is basically how fast you move through the air mass. At any altitude, with no wind, this will equal ground speed. At altitudes above sea level, this will be faster than indicated air speed because the thinner air results in reduced pressure differentials and fewer air molecules passing the aircraft. This speed can also be understood as how fast the air molecules pass the aircraft.

    Ground speed: same as your car speedometer, how fast you are moving relative to the ground.

    Because the earth's air mass moves with rotation, the earth's rotation does not significantly factor into these speeds. Typically you see faster ground speeds flying east than west because the prevailing winds at altitude are from west to east.

    This said, the right combination of a hot day, high altitude, and a very strong tail wind can result in subsonic airspeeds being higher than a no wind, supersonic ground speed.
     
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  8. Tony C. Ωf Jury member Aug 6, 2016

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    @bronxbomber252 In future, I'll be targeting any aviation questions in your direction. :thumbsup:
     
  9. al128 unsolicited co-moderation giverer Aug 6, 2016

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    That! And his bucket full of coffee was running low and he panicked, took the nose down and stepped on the loud pedal on his way DD
     
  10. abrod520 Aug 6, 2016

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    Yeah - thought maybe the DirecTV system got fooled by it somehow though :) Don't know if the airspeed displayed in the TV console comes from the instrumentation (in this case, I'd hope not) or from satellite signals
     
  11. bronxbomber252 Aug 6, 2016

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    DirecTV doesn't have location services. The speed is likely ground speed and likely comes from GPS
     
  12. Pvt-Public Aug 6, 2016

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    It was tracking ground speed the maximum operating air speed for the A321 is .82 mach (542 knots, 624 mph). And these figures change with altitude, temperature, barometric pressure, and probably a few other things.
     
  13. ulackfocus Aug 6, 2016

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    I have hyperdrive on my Toyota, so it's no stretch for a passenger jet to fly above Mach 1 to me. :p
     
  14. Mad Dog rockpaperscissorschampion Aug 6, 2016

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    Ummm...no...I can't [don't] fly planes that play Marky Mark & The Funky Bunch. ;)

    image.jpeg
     
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  15. chadpowe11 Aug 6, 2016

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    Correct
     
  16. Perseus Aug 8, 2016

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    You never whats going to happen then they pump some Marky Mark!

    [​IMG]
     
  17. RegF Aug 8, 2016

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    Was there a "boom"?

    Or only a "tish"? ::rimshot::
     
  18. Pvt-Public Aug 8, 2016

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    Oh yes I do ! !
    ::puke::::puke::::puke::::puke::::puke::
     
  19. abrod520 Aug 8, 2016

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    Only sound I heard was this



    Thankfully, it was only the audio, no video :D
     
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