1. A380

    A380 Member

    Yes and the most photos from planes and weather. But it was not so bad für the camera: http://olegkikin.com/shutterlife/nikon_d60.htm


    Back to topic - this is, what also use skywriter:

    [​IMG]

    [​IMG]

    The weather was unhappily not so good …
     
    Last edited by a moderator: Nov 20, 2013
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  2. Here are couple of shots of a halo with edge shadows. I should have taken video. 431935_10151450110083932_1889036780_n (1). 179189_10151450110208932_52435717_n (3).
     
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  3. Pete Tar

    Pete Tar Moderator Staff Member

    Wow it looks like a Star Trek logo!
     
  4. Brandon

    Brandon New Member

    What's the science behind those contrails that don't involve a heat source? Instead of looking it up, I'm going to guess. Tell me if I sound right, Mick, eh?

    With an engine, you inject so much energy into the individual air molecules that they can no longer involve water in their structure. They separate and the water comes out gaseous and hits cold air. Poof. With just a wing, any moving object, the low pressure systems created by an object zipping through air (Bernoulli), they must create a vacuum, or a near vacuum, and the air that rushes to fill it accelerates too hard for the structure to contain water, water comes out gaseous, etc..

    Or is it just friction? Friction creating heat, just like an engine. I don't know, but I know airplane wings don't get hot. I'm just guessing here. It's not static. Static looks

    [Admin: moved sub-discussion to]
    https://www.metabunk.org/threads/1681-The-Kopp-Etchells-Effect-(Helicopter-Light-Halo)

    How's my science sound, Mick?
     

    Attached Files:

    Last edited by a moderator: Nov 20, 2013
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  5. Mick West

    Mick West Administrator Staff Member

    Heat-less contrails are aerodynamic contrails, it's simply the reduction in pressure lowering the saturation point of the air so that water condenses out. It can leave a longer trail in the middle of a vortex (often at the end of flaps when landing), or very short trials (regions) on the tops of wings. In rare circumstances they can freeze and persist.
     
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  6. Brandon

    Brandon New Member

    Two low pressure zones facing each other, water freezes out. Gotcha.
     
  7. Joe

    Joe Senior Member

    AIR+SHOW+068.JPG

    AIR+SHOW+072.JPG

    stuart air show
     
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  8. Mick West

    Mick West Administrator Staff Member

    As for "Two low pressure zones facing each other, water freezes out." I'm not even sure what you mean by that. All you need is one region of low pressure, and water will condense.
     
  9. A380

    A380 Member

    The A380 has condensations above the engines:

    [​IMG]

    [​IMG]
     
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  10. Brandon

    Brandon New Member

    I call the contrails two low pressure zones just because there are two sides to the tip of the wing there, and I'm actually amazed that no more than a moving object can do that. I've never seen a contrail from a wing tip before.
     
  11. Jay Reynolds

    Jay Reynolds Senior Member

    An analogous action occurs in water which might be easier to conceive.
    Boat propellers do a similar thing, low pressure areas under water are able actually generate 'steam' at much lower temperatures than you would think. This also happens inside of pumps and eventually will cause metal damage because the vapor collapses and the sudden collapse induces a jet of in-rushing fluid impingement to the surface causing erosion. It is a problem for submarines because of noise generation.

    View attachment 3080
     

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  12. Mick West

    Mick West Administrator Staff Member

  13. justanairlinepilot

    justanairlinepilot Active Member

    http://en.wikipedia.org/wiki/Wingtip_vortices
     
  14. Joe

    Joe Senior Member

    march 2nd 2013 010.JPG march 2nd 2013 013.JPG F-14 tomcat Old Daytona Rd Deland Fl , Being from Long Island married into a Grumman Family The Tomcat is My favorite aircraft , My father in law worked on every Tomcat built from Inception to last Tomcat . Including The Iranian Tomcats which I believe are still used today . I collect anything Tomcat .
     
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  15. pseacraft

    pseacraft Active Member

    Not as good as many of the others posted but this is what I came home to this afternoon. Thankfully the aerial crews are very good as there are no fire breaks for the regular crews below my house.

    Lofou Fire June 2013_01.
    Bell Griffin HAR2 (Bell 412EP Varient) RAF 84 Squadron ZJ706

    Lofou Fire June 2013_02.
    Ayres S2RHG-T65 Thrush Commander, Cypriot Department of Forests FD-2

    Lofou Fire June 2013_03.
    Air Tractor Inc AT-802, Cypriot Department of Forests FD-1

    These are from last August's fire that nearly got my old house. Fire season here really sucks as does cleaning the foam and soot from inside your house.

    Vouni Fire Aug 2012_01.
    Kamov KA-32AO Pankh RA-31571

    Vouni Fire Aug 2012_02.
    Ayres S2RHG-T65 Thrush Commander, Cypriot Department of Forests FD-2

    Vouni Fire Aug 2012_03.
    Air Tractor Inc AT-802, Cypriot Department of Forests FD-1
     
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  16. PCWilliams

    PCWilliams Active Member

    That is an AWESOME shot!!! What a monster!
     
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  17. A380

    A380 Member

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  18. GregMc

    GregMc Senior Member

    I thought I'd post some not so awesome shots as those above, but pictures that show how pedestrian contrails are to the general population. Not a cause of fear but instead more likely of jealousy . These are pictures taken at Sydney Australia's "sculpture by the sea" annual exhibition, where the headlands close to the famous Bondi beach are populated with sculpture artworks. The exhibition attracts hundreds of thousands of visitors. On the day I visited with my family there was a number of large highly visible contrails right in the public's direct eyeline, impossible to miss seeing. Probably many tens of thousands of folk all going about the activity of studying the aesthetic of things would have witnessed the trails. Rather than expressions of fear and horror, I did overhear a few people mention the trails and say things along the lines of "shame for those passengers to be leaving Australia on such a beautiful day" etc. In other words, to the majority of general public the trails are just a normal aspect of passenger aviation exactly as they have been for most people for many decades. It's sad that a tiny minority of the population unfortunately seem to have walled themselves up in a cloister of fear that ruins their quality of life. http://static.ipaustralia.com.au/store3/15/46/1546070.1.high.jpg
    IMG_6155.JPG IMG_6150.JPG IMG_6179.JPG IMG_6154.JPG
     
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  19. TEEJ

    TEEJ Senior Member

    Hi,
    Apologies for the late reply. I would imagine that it is automatic deployment. The pilot selects the wing sweep and the slats deploy accordingly. Some other images of slat deployment during flights at low level.

    [​IMG]


    [​IMG]
     
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  20. captfitch

    captfitch Active Member

    Automatic as it is on many aircraft like this. To decrease complexity the slats are held in aerodynamically and only deploy under high angles of attack when they are most needed. No large aircraft have this.
     
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  21. TEEJ

    TEEJ Senior Member

    Final batch from my archives.

    Swiss F/A-18 Hornet


    [​IMG]


    Belgian F-16. Smoke also features as generated from the wing tip 'smoke winders'


    [​IMG]


    RAF Typhoon


    [​IMG]


    RAF Typhoon


    [​IMG]


    RAF Typhoon - Fuel vent from fin.


    [​IMG]


    French Air Force Rafale


    [​IMG]


    RAF Typhoon


    [​IMG]


    RAF Red Arrows


    [​IMG]


    RAF Tornado


    [​IMG]
     
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  22. MikeC

    MikeC Senior Member

    Are tornado slats held aerodynamically? that seems awfully crude for a modern high-tech a/c - I would have thought the on-board computers might control their deployment.

    the last a/c I heard of having aerodynamic control of slats were WW2 fighters - the Me-109 apparently "snatched" quite viciously (pdf download link) when they popped out if the a/c was not in a co-ordinated turn.

    I think some Soviet fighters had them too.

    In a bit of reading for this post I see that F-86 and Sabreliners apparently also had them.

    Edit: apparently F-16's and A-4's have/had too.....
     
  23. captfitch

    captfitch Active Member

    Yeah, I think it's pretty common. I remember an aircraft I walked up to where I could push the slats in pretty easily. Thought it was an a-4.
     
  24. MikeC

    MikeC Senior Member

    There are 2 types of aerodynamic activation - on the A-4 and others the slats are deployed by spring pressure, and gradually retract as air pressure from forward speed overcomes that and pushes them in.

    On the Me-109 and soviet fighters the slats are normally shut, and it is a low pressure acting on them that opens them - probably at high angles of attack.
     
  25. JRBids

    JRBids Senior Member

    993589_10200841010781864_295423544_n. 1015173_10151622680786702_215419997_o.

    I just thought this was interesting. There was a beautiful sunset tonight. I posted the top photo on Facebook. A little while later a friend posted the one below. It's obviously the same contrails. His photo is on the Hudson River looking west. Mine is on eastern Long Island, looking west. The trails are west of HIM. I am over 100 miles EAST of him. So tell me again how the CTers can tell how far away the trails are, and can smell them "overhead".
     
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  26. TEEJ

    TEEJ Senior Member

    A few more that escaped my final trawl.


    Italian Air Force C-27J Spartan


    [​IMG]


    Privately owned Hawker Hunter venting fuel after take-off.


    [​IMG]


    Hungarian Air Force Saab Gripen venting fuel that ignites.


    [​IMG]
     
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  27. David Fraser

    David Fraser Senior Member

    Wow TEEJ. I have just had a flashback. I am from Hessle not far from Brough. I have a few relatives, and as a kid neighbours, that worked at BAe (then Hawker Siddeley) and I remember sitting in a Hunter at one of the open days. This is back in the 70's mind.

    On a side note I recently made FB contact with an old school friend who went to BAe (a common career choice at my school). He works around but has worked on the Gripen, well the wings.

    When in the army I was airborne but I have very little interest in aircraft. However may I say that I find your photos an absolute joy and pleasure. Thank you :)
     
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  28. TEEJ

    TEEJ Senior Member

    Hi Dave,
    Many thanks for you very kind words. The Hunter a fine aircraft and one of my favourites.

    Cheers
    Tom
     
  29. cloudspotter

    cloudspotter Senior Member

    http://www.bbc.co.uk/programmes/p018t3xg

    A new series just started on the BBC. Interesting stuff. They've just been going through a walk around inspection on an A380 and stopped to look at the heated drain mast.
     
  30. TEEJ

    TEEJ Senior Member

  31. cloudspotter

    cloudspotter Senior Member

    I didn't get to watch the whole show properly but I was hoping some chemtrailers were watching when they were covering the detailed inspections the planes go through.
     
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  32. David Fraser

    David Fraser Senior Member

    I have just caught up on them all. I wonder how many chemtrailers have watched it so far. It has shown some really interesting insights into the maintenance and logistics required at an airport. I wonder if some have had a lightbulb moment and thought "Hang on a minute. That is a lot of people at one airport involved in this".
     
  33. Joe

    Joe Senior Member

    F-14 with contrails DSCF4598.JPG
     
  34. Met Watch

    Met Watch Moderator

    [​IMG]

    Photograph Credit: Ken Lee, a spotter for the National Weather Service in Sacramento. Shared by NWS Sacramento.
     
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  35. Cairenn

    Cairenn Senior Member

    OH NO!!! They are spraying chemtrails on the moon!
     
  36. A380

    A380 Member

    On the way to the moon:

    [​IMG]

    It was a very cold morning, the heat rose from the houses. Therefore, there was strong flickering in the air.

    Here it was better:

    [​IMG]

    And 738 from SunExpress:

    [​IMG]

    Winglet with moon over the Mediterranean:

    [​IMG]
     
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  37. cloudspotter

    cloudspotter Senior Member

  38. cloudspotter

    cloudspotter Senior Member

  39. cosmic

    cosmic Senior Member

    Flickr imagery requires additional steps.

    1) Under the Flickr image you wish to insert here, click on the "more ways to share" button [​IMG]
    2) From the pop-up menu, select "Grab the HTML/BBCode"
    3) Select the desired size from the pull-down menu
    4) Click the radio button for BBCode
    5) Then copy and paste the code into your post, and voila:

    [​IMG]
    IMG_2106 by Mr Thumpy, on Flickr
     
    Last edited by a moderator: Nov 20, 2013
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  40. cloudspotter

    cloudspotter Senior Member