1. Trailspotter

    Trailspotter Senior Member

    It's called 'distrail'.
    • Agree Agree x 1
  2. Clouds Givemethewillies

    Clouds Givemethewillies Active Member

    Not cirrus, but a supercooled water cloud. eg. altostratus.
    • Agree Agree x 1
  3. Leifer

    Leifer Senior Member

    Thanks for the clarifications.
  4. Trailblazer

    Trailblazer Moderator Staff Member

    Lots of contrails over the French Alps on Tuesday, including several loops. I didn't get a good look at what was making them as it was was often hidden behind the mountains. Maybe Airbus test flight again? In the first pic if you zoom in you can see the more distant loops to the left of the mountain.

    There were circles and spirals in the sky for much of the middle of the day.

    IMG_0637.JPG IMG_0662.JPG
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  5. Skaredstiff

    Skaredstiff Member

    Nice day at Sierra at Tahoe today. Good day for contrails at various altitudes. Been up the last two days with very few visible contrails. Weather has been crystal clear and warm. Seems like a pressure change and some temp drop on the way. Weather forecasted in the next few days. Hope you aircraft trackers have fun identifying these flights. Mostly just air traffic on a day where conditions make it look sinister?
    Last edited by a moderator: Mar 16, 2017
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  6. Trailblazer

    Trailblazer Moderator Staff Member

    Lots of contrails this morning, and some striking shadows where the trails lined up with the rising sun.

    IMG_1150.JPG IMG_1162.JPG IMG_1174.JPG

    Edit to add screenshot showing the high humidity over much of the UK this morning. I'm in the red circle:

    Last edited: Mar 30, 2017
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  7. Trailblazer

    Trailblazer Moderator Staff Member

    There was an almost identical photo (bottom left) posted on Chemtrails Global Skywatch yesterday from someone living in Bracknell:


    Interesting to see the same trails from a slightly different perspective:
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  8. Trailblazer

    Trailblazer Moderator Staff Member

    Contrail shadow from my back garden a few minutes ago. The clouds are moving quite fast so it was only aligned to make the "beam" for 20-30 seconds.


    Aligned perfectly with the sun:

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  9. Clouds Givemethewillies

    Clouds Givemethewillies Active Member

    Some stonking great trails the evening! baw85q.PNG DSCF4534 baw85q.
    • Like Like x 6
  10. Trailblazer

    Trailblazer Moderator Staff Member

    Stopped on the way to the station this morning to grab this photo of two long trails and a short one:


    I didn't have time to ID the flights there and then but have just checked it out:


    The photo was taken from the red dot in Farnborough, looking just south of west (the front of the house faces pretty well due east). The two persistent trails are BY1360 and DY4275, at 35,000ft and 34,000ft respectively, and the non-persistent one is DL411, at 37,000ft.


    Not much height difference needed for a big change in the appearance of the contrails.
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  11. deirdre

    deirdre Moderator Staff Member

    I think this is a distrail ?? on the edge of some clouds. the sun is setting so I think if it was a shadow it is on the wrong spot ?? (the dirt smudges are either my window or something with the camera up against the window)


    • Like Like x 1
  12. Mick West

    Mick West Administrator Staff Member

    Looks like a distrail, but there's also a contrail there - so it's more like the gap left by a contrail (probably aerodynamic) forming in or above a layer of clouds. It's in a very thin layer round the sides, so it gives the illusions of looking like it forms one edge of the cloud layer.
    • Like Like x 2
  13. Trailblazer

    Trailblazer Moderator Staff Member

    This contrail last night spread out in quite an unusual way.


    • Like Like x 6
  14. Radapox

    Radapox New Member

    IMG_20170805_122654_HDR. Got meself a neat distrail just now. (Western Netherlands)
    • Like Like x 7
  15. Whitebeard

    Whitebeard Senior Member

    Spent the weekend at a music and astronomy festival in Builth Wells, mid Wales, snapped some nice trails and clouds while I was there.
    P8120067.JPG P8130078.JPG P8120068.JPG P8130081.JPG
    • Like Like x 4
  16. Joe

    Joe Senior Member

    DSCN0339.JPG DSCN0337.JPG LA to Orlando . Over Arizona
    • Like Like x 3
  17. JFDee

    JFDee Senior Member

    That's a textbook thunderstorm anvil ... An exhibit for the WMO cloud atlas perhaps.
    • Like Like x 1
  18. deirdre

    deirdre Moderator Staff Member


    Attached Files:

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  19. derwoodii

    derwoodii Senior Member

    not the most persistent contrail but the skiing was good at Mt Baw baw Victoria Oz looking east a plane on way to new zealand

    • Like Like x 1
  20. Trailblazer

    Trailblazer Moderator Staff Member

    One plane with a contrail and one with none at all this evening. (You might need to open the full-size pic to see the other plane: its almost exactly level with the one with the contrail, and one third of the width of the photo to the right.)


    On the left, BY1124 at 37,000ft, on the right, FR5209 at 35,000ft.

    IMG_4917.PNG IMG_4918.PNG IMG_4919.PNG
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  21. cloudspotter

    cloudspotter Senior Member

    Halo plus Lufthansa A340 Chicago - Munich

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  22. Trailspotter

    Trailspotter Senior Member

    Saudi flight SVA123 to Manchester today was put on a high-altitude hold over England due to thick fog at the destination. It was flying an unusually big racetrack pattern at 37,000 ft for nearly two hours:
    Screen Shot 2017-09-19 at 09.45.06.
    The racetrack was to the west of my location with the closest point some 20 miles away. Below are a few frames from the video that I've taken before clouds arrived:
    Screen Shot 2017-09-19 at 15.18.01.
    Screen Shot 2017-09-19 at 15.19.20.
    Screen Shot 2017-09-19 at 15.16.47.
    Sadly, the plane (Boeing 787 Dreamliner) was leaving only short contrail at the time :(

    PS The full video can be watched here.
    Last edited: Sep 19, 2017
    • Like Like x 2
  23. Trailblazer

    Trailblazer Moderator Staff Member

    Very heavy contrail coverage this morning. A rain-bearing front is due to arrive this afternoon.

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  24. Trailblazer

    Trailblazer Moderator Staff Member

    As predicted there was heavy rain yesterday afternoon, and 24 hours after that last picture there's not a trail (or cloud) in sight.


    Here's a GIF showing how the relative humidity at 250mb changed in that time, at my location (circled):

    Last edited: Sep 22, 2017
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    • Informative Informative x 1
  25. M Bornong

    M Bornong Senior Member

    I think I caught a fuel dump. FedEx #9000 out of Los Angeles. It was on for about 2 minutes, then stopped. The trail was visible for just a couple of minutes.
    Dumping1. flightradar.

    I thought it was a little strange when it made a few low passes over Sacramento, then finally landed back at LAX, it was shadowed by FedEx9043 the entire Way. They must have been testing something or other.

    multiselect. Landing.

    Were 9000 and 9043 the same plane with a glitch? I could clearly see 1 before the trail started, I never saw 2 planes, and they were always right on top of each other showing pretty much the same altitude and speed..

    Attached Files:

    • Informative Informative x 2
  26. Trailspotter

    Trailspotter Senior Member

    They almost certainly were the same plane, DC10 N307FE. I've seen similar FR24 'glitches' before on passenger flights, where two flights were merged (due to cancelation or other reasons). BTW, planefinder.net playback shows only one flight, FDX9000:
    Screen Shot 2017-09-25 at 07.48.02.

    There are no reports on any incidents with this plane yesterday (yet), e.g., in http://avherald.com/.
    From the recorded track, the plane attempted to land in Sacramento, missed approach and then returned to LAX. Or all this was just a training exercise, including fuel dump.
    Last edited: Sep 25, 2017
    • Informative Informative x 1
  27. M Bornong

    M Bornong Senior Member

    I'd also think that if a plane was in distress they'd put the other planes coming into and out of Sacramento into a hold while it was attempting to land. While it did it's 2 circles several other planes did land.
  28. Trailspotter

    Trailspotter Senior Member

    It could be a minor incident thad did not require emergency landing. I gathered that not all minor incidents are reported promptly, if reported at all. The plane in question had a reported incident earlier this year. Keep checking Aviation Herald for the next few days, or report your observation to them, they may check themselves whether it was an incident or training exercise.
    • Like Like x 1
  29. Clouds Givemethewillies

    Clouds Givemethewillies Active Member

    FlightAware GE track.

    Attached Files:

  30. Trailblazer

    Trailblazer Moderator Staff Member

    Did the trail spread out like a contrail before it disappeared?
  31. M Bornong

    M Bornong Senior Member

    After the initial pluming, seen in the first half of the trail, it pretty much held the same same shape as what you see towards the right hand side of the photos, it did expand to maybe double what is shown. It never developed any little puffs or tendrils. It was just a continuous fade out.

    This is the full sequence with the times taken from the exif, we are 7 hours behind UTC, the clock in my camera is 2 minutes ahead of the flight radar clock. It happened quicker than I thought, the only delay from when it started dumping was the reflex time to raise my camera and get a decent lock on it. These are not cropped and no enhancement.

  32. A pair of contrails this afternoon above Missoula Mt. The planes flew over next.to each other about 5:20 MDT. I think there are 2 sets of shadow pairs, one far lower right. 20171005_172659.
    • Like Like x 3
  33. Here's a horizon to horizon shot. 20171005_172854.
    • Like Like x 3
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  34. Clouds Givemethewillies

    Clouds Givemethewillies Active Member

    Quite a high persistent contrail, but some way off the record. shcc.PNG Capture2.PNG mst 24 10 17.
    Last edited: Oct 25, 2017
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  35. Trailblazer

    Trailblazer Moderator Staff Member

    Is that a GPS altitude? The reported altitude (ie flight level) was 40,000ft according to FR24.


    The sea-level pressure is only about 1021mb so I wouldn't have thought that would account for such a difference in pressure altitude, although it is quite a warm airmass which would make the levels higher.
    • Like Like x 1
  36. Clouds Givemethewillies

    Clouds Givemethewillies Active Member

    It is the ADSB reported altitude, based on pressure. SHCC was set to an offset of 1847 ft. to track.

    Edit: I will check whether I add this offset to the reported altitude to get geometric altitude, or just move the dot.

    Yes, it includes the offset. I think I should change that as it depends on fitting as well as the barometric offset.
    Last edited: Oct 25, 2017
  37. Clouds Givemethewillies

    Clouds Givemethewillies Active Member

    A bit higher, subtract 2.300ft Capture.PNG Capture2.PNG
  38. Trailspotter

    Trailspotter Senior Member

    GLEX G-XXRS contrails.
    TAG Aviation UK Bombardier Global Express G-XXRS flying non-stop a 6,800 NM route from CJC, Calama, Chilie to KBP, Kiev, Ukraine on October 22, 2017 passes over the Strait of Gibraltar at 43,000 ft at 15:40 UTC, leaving a long persistent contrail. A close up of the plane and its contrail and a relevant segment of the route are in the video.
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  39. Trailblazer

    Trailblazer Moderator Staff Member

    Noticeable colour difference (reddish/blueish) between these two backlit trails. Presumably down to the angle of the sunlight.


    Edit to ID the planes. Delta DL84 (37,000ft) is the reddish trail (as seen on the screenshot) and United UA53 (32,000ft) is the other. Both Boeing 767s.
    Last edited: Oct 31, 2017
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  40. Marin B

    Marin B Active Member

    Over British Columbia - Fortress Lake, I believe.
    Not sure if there are contrails in this shot or just regular cirrus. But thought it was too pretty not to share.
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