Squiggly Sinusoidal Thin Contrails over Europe

Mick West

Administrator
Staff member
Update: See likely explanation here:
https://www.metabunk.org/threads/si...y-hybrid-contrails-the-rook-instability.4539/


Photo: Christophe EECKHAUT, (c) CAELESTIA/Belgisch UFO-meldpunt




Photo: André DILDICK, (c) CAELESTIA/Belgisch UFO-meldpunt




Via email:

In the course of January and February the Belgisch UFO-meldpunt/Belgian UFO Reporting Centre (please note that this is a group dedicated to explaining mysteries, not promoting them) received two photographs of an unusual “contrail” (see attachments). Both pictures were shot in the morning of January 12, 2014. The first photo was taken by Christophe EECKHAUT with an Apple Iphone 5 while standing at the AF base of Koksijde, not far from the Belgian coast (see map). Time was 08:46:18 CET according to the photo’s EXIF data. The photographer reports that he saw an airplane with a short contrail fly over the base when a second trail formed to the right of the plane. What surprised Mr. EECKHAUT and the five colleagues that were with him, was that this trail was not straight but appeared to be zigzagging (“It remained at the same level as the plane but rocked from one side to another. Suddenly the deformed trail stopped and nothing more was visible”). Both airplane and trail were moving East. The sighting lasted about 15 minutes.


The second photo was taken 7 minutes later (at 08:53:24 to be precise) by André DILDICK from the community of Gistel, 23 km ENE of Koksijde. Mr. DILDICK observed the trail as it moved from the S to the SE. Here too, the duration was estimated at circa 15 minutes. Captured with a Sony HDR-SR11E, this picture is of much better quality. A quick examination of the trail’s wave pattern reveals that it's identical in both shots.


We wonder how this solitary trail may have formed. A "hybrid contrail" is not a good option, I think. If that were the case, we should be looking at two distinct trails with the typical chromosome pattern. Sky writing seems unlikely too because of the smooth and capricious aspect of the trail. Moreover, similar (illegible) trails were photographed over Malderen, Belgium on March 3, 2002 (personal files, photo on request), and over The Netherlands on February 18, 2013 (see https://www.nufoto.nl/fotos/329227/condenssporen-boven-den-haag.html, and http://www.ufomeldpunt.nl/melding/2201-sporen-in-de-lucht), and again on March 4, 2013 (http://www.ufomeldpunt.nl/melding/2313-vliegtuigspoor-met-daarachter-witte-lijnen-letters). Oddly, I found no examples from places outside the Low Countries.

As a regular visitor to your excellent sites, I was wondering if you have any idea how these unusual trails may have formed?
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It should also be emphasized that both photographers indicated that they heard no sound. That would not only rule out a helicopter ejecting smoke or flares, but also a jet and a small plane.
So if I'm not mistaken we envisaged five possibilities already:
- normal contrail (to be ruled out because too smooth and wavery and only one trail instead of two);
- hybrid contrail (not entirely impossible since the photo taken at Koksijde AFB shows an airliner with a short contrail flying parallel to the unidentified trail, whilst the photo from Gistel shows what looks like a smaller airplane with no contrail just "above" the trail, but here too only one trail);
- sky writing (too smooth in appearance and there's no readable message);
- pyrotechnic flare deployed by a military plane or helicopter (such flares are usuallly short-lived and leave a smoke trail, not a vortex-like trail like the one in the pictures);
- relatively small, malfunctioning rocket (best option perhaps)
Could it be a fluid that was dumped by a plane? If so, it must be something quite exceptional considering that such trails are extremely rare.

Note also that on the photo taken from Koksijde there's an unusual object in the bottom centre of the picture. According to the photographer this object also appears in a second picture he took of the phenomenon. As a matter of fact, it now turns out that this AFB employee took not one but three photos. I haven't received the other two yet, but I will forward them to you as soon as I get them myself.

For what it's worth, these are the ground weather data from the meteorological station at Bruges, Sint-Andries (15.3 km ENE of Gistel) between 8:50 p.m. and 8:53 p.m. CET:
Temp.: -0.9°C
Dewpoint: -2.2°C
Pressure: 1023.6hPa
Wind direction: SSE
Wind speed: 1.3 km/h
Humidity: 91%
Balloon soundings are not available, alas.


Wim VAN UTRECHT

www.caelestia.be
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These are very interesting trails, they have the appearance of the hybrid part of a contrail (the portion of an exhaust contrail made more dense and persistent by the wake vortex), which you often see in loops and curls, but in pairs, and broken up. Like:
http://contrailscience.com/hybrid-contrails-a-new-classification/


Yet the squiggly trails are continuous single trails.

They are not just over the Low Country (Netherlands/Belgium), here's a reported example over Poland showing identical structure.
http://projectavalon.net/forum4/showthread.php?45677-interesting-contrail&p=496936#post496936



These photos appear to show a similar phenomenon over Kansas City, USA. With the trail starting squiggly, and getting progressively more so:
http://geekswithblogs.net/jjulian/archive/2007/12/17/117790.aspx
 
There's something fishy about that first photo. I would say that there was a very brightly lit, reflective, jet that they took a long exposure of and moved the camera. The motion looks repetative, there are little flare-ups in the line and it's almost perfectly uniform throughout. It's just too perfect. So they long exposed the jet and then held the camera still to get the background.
 
One theory I have is that this is a contrail that has become entrained in a horizontal rolling mass of air. Essentially a normal contrail that has been "rolled up" and only the dense core survives, and get progressively more sinusoidal.

I don't feel this adequately explains the first photo though, as the curves are so dramatic, and the contrail very solid looking. However, consider the two photos taken seven minutes apart.



Clearly the amplitude of the squiggle has increased greatly in seven minutes. The trail itself also seems to have thickened and spread. This suggest that like the Kansas example it did not start out so dramatically squiggly. Could it have started as a straight line, and then a rotor, or series of rotors in the air have formed it into this type of trail?

[Update] I had the order of the photos the wrong way around. The more compressed photo seems to be more from perspective foreshortening. Wim sent me this photo with a better correction for perspective:


Consider this cloud:


It's a cloud that is twisted inside a rotor of air. Now imagine the cloud is not there, and a plane comes along and leaves a contrail. Could it create the squiggly thin trails we see in the photo?
 
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There's something fishy about that first photo. I would say that there was a very brightly lit, reflective, jet that they took a long exposure of and moved the camera. The motion looks repetative, there are little flare-ups in the line and it's almost perfectly uniform throughout. It's just too perfect. So they long exposed the jet and then held the camera still to get the background.

i don't think so, as it's very similar to other examples, with the little flare-ups (which you see in the hybrid contrails, exactly the same). Compare with the second photo from Poland. This is just an exceptionally nicely lit example.
 
It's a cloud that is twisted inside a rotor of air. Now imagine the cloud is not there, and a plane comes along and leaves a contrail. Could it create the squiggly thin trails we see in the photo?
that would explain the inconsistency. I was thinking propeller but the inconsistency didn't make sense.
 
Could they be contrails spiraling in horizontal atmospheric vortices?

http://journals.ametsoc.org/doi/abs/10.1175/1520-0469(1965)022<0176:LEITAB>2.0.CO;2

Turbulent shear flow generally contains large eddies which appear to be due to a shear instability of the profile of the mean flow. By analogy with laboratory experimental results, it is inferred that large eddies in the planetary boundary layer of the atmosphere should take the form of horizontal roll vortices with an orientation between that of the surface wind and that of the geostrophic flow.
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Could they be contrails spiraling in horizontal atmospheric vortices?

http://journals.ametsoc.org/doi/abs/10.1175/1520-0469(1965)022<0176:LEITAB>2.0.CO;2

Turbulent shear flow generally contains large eddies which appear to be due to a shear instability of the profile of the mean flow. By analogy with laboratory experimental results, it is inferred that large eddies in the planetary boundary layer of the atmosphere should take the form of horizontal roll vortices with an orientation between that of the surface wind and that of the geostrophic flow.
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That's essentially what I meant when I said "a contrail that has become entrained in a horizontal rolling mass of air" above.

"Corkscrew" contrails happen, here's one that's obviously shaped by the rotors that form the row clouds:


 
What do I know but something doesn't fit right with me, the proportions vs how much they've been distorted from their laid-in-a-straight-line original, plus the varied reflectivity and the "positions" of those high points. Looks more like a "special" effect or as mentioned above - a vibrating camera.


Though I've heard some pilots do like a drink or two...
 
What do I know but something doesn't fit right with me, the proportions vs how much they've been distorted from their laid-in-a-straight-line original, plus the varied reflectivity and the "positions" of those high points. Looks more like a "special" effect or as mentioned above - a vibrating camera.

There's far too many different examples of the same thing. I see no reason to suspect any of the photos.
 
What do I know but something doesn't fit right with me, the proportions vs how much they've been distorted from their laid-in-a-straight-line original, plus the varied reflectivity and the "positions" of those high points. Looks more like a "special" effect or as mentioned above - a vibrating camera.


Though I've heard some pilots do like a drink or two...
I think it just got shorter (in viewable length) like if you wrap a hair round your finger.
 
There's far too many different examples of the same thing. I see no reason to suspect any of the photos.

Yeah, probably, just thinking out loud without thinking too hard lol.

I think it just got shorter (in viewable length) like if you wrap a hair round your finger.

Yup, could be, just my feeble mind can't imagine why the high-vis points are where they are.
 
Yup, could be, just my feeble mind can't imagine why the high-vis points are where they are.

Well, note the first two photos are taken from different positions, miles apart. I forgot to add this image, which is Wim's estimate of the position of the trail:
 
Windshear, at altitude.

I know there was a long and scientific explanation....but when people begin to learn about windshear, at altitude, then they will begin to better understand why to keep their seatbelts fastened.

In this case the windshear affected the contrails, after the airplane passed. But, again....in clear air, these sorts of air currents cannot be detected. Unless encountered physically, in some way. OR if they happen to manifest due to condensation, and then become visible due to the clouds that are formed as a result.
 
It sort of looks like a missile/rocket trail. Were there any rocket launches at the time the photos were taken?

European Space Agency astronaut Luca Parmitano captured this shot of a contrail from a Russian missile. The zig-zag shape of the contrail is due to winds at various heights of Earth’s atmosphere. Here’s what bloggers at the Russian Nuclear Forces Project said about the October 10 Russian missile test:
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missile1.jpg
http://earthsky.org/todays-image/russian-missile-contrail
 
I don't think it really looks at all like a rocket trail. It's far too thin, dense, and clean. By the time a rocket trail has got that squiggly, it's broad and fluffy.

And nobody fires rockets over London.
 
I don't think it really looks at all like a rocket trail. It's far too thin, dense, and clean. By the time a rocket trail has got that squiggly, it's broad and fluffy.

And nobody fires rockets over London.

Every experience can be different. Not arguing, just suggesting.

OH, this was over Great Britain? I need to read the thread more fully.
 
Every experience can be different. Not arguing, just suggesting.

OH, this was over Great Britain? I need to read the thread more fully.

There were multiple examples, two were over London, others over The Netherlands, Belgium, the US (Kansas City), and Poland.
 
Update From Wim:

Meanwhile I found a discussion of another sinusoidal contrail over Heathrow, London. This one was spotted on November 19, 2005 (the video you posted on the Metabunk forum was from September 1, 2001). The "new" discussion is from Weather Vol. 61, No. 7 and 12. You will find it at:

http://onlinelibrary.wiley.com/stor...q6&s=b84ede1ef29047b3c8d5528ae60624e012b49bab

and

http://onlinelibrary.wiley.com/stor...iw&s=89facc08a2ecbda95fee77af8601034b4a97d000

What appears to have been the same contrail was also discussed at http://www.pprune.org/spectators-ba...9072-strange-contrail-south-london-today.html.

No definite answers here either.

I also mentioned the Metabunk discussion to my loyal correspondent Martin SHOUGH, UK Research Associate for the U.S. National Aviation Reporting Centre on Anomalous Phenomena (NARCAP). In a mail ofMarch 1st Martin commented as follows:

"Thanks for this. Fascinating! I have never seen quite this effect before. After scrolling through them, my impression is that they are caused by a trail that happens to be left exactly at the boundary of a sharp (narrow) high-level inversion layer. There are two effects operating: one is waves propagating across the surface of the layer, the other is a sharp wind shear across the layer. I think the waves push the trail into a vertical sinus whose amplitude is the depth of the inversion, allowing the wind shear to operate differentially on the peaks and troughs. But another thing is that the trail seems to be affected almost solely by this mass flow, hardly at all by internal diffusion/spreading. Partly this would be because of being in the inversion, which is the definition of stable air having little or no thermal mixing going on. But I don’t think that’s the whole story. It seems to be behaving as if stabilised by vorticity, keeping it tight, and this seems unusual for a single trail of this type. So I wouldn’t say it was properly explained yet. I’ll keep looking and thinking and maybe ask around..."
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That's the way it seems to me. The lower stratosphere is mostly laminar in behavior. Rolling sheets of air (vortices) may be gently squeezed almost flat, until, at least, they exhibit Crow Instability, and form loops at right angles to themselves. It's all very stable behavior. A rotational moment of inertia is another form of stabilization. How counter-rotating vortices become this is still a mystery.

Vortices stick to flat surfaces due to the low pressure on their rotational axis: then maybe the vortices consider the topside of the inversion to be a "surface", and "print" themselves as a sinusoid upon that "surface", to Crow's rules. Maybe…

What a fabulous run of images, Mick. :)
 
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Crow's rules...

Can't help myself, I immediately flashed in my mind, the HBO program "Game of Thrones" (Subtle reference).

But yes, in terms of the 3-D aspect of the atmosphere and the extremely complex interactions that occur, this is a concept that seems foreign to many peoples' understanding. Since they (those people) are most familiar usually with surface travel, which is a sort of "2-D", in a way.

Enjoy this short clip!:
 
Here are some pictures taken in Sofia, the capital of Bulgaria (Eastern Europe).
The pictures are shot at 2010 March 18, around 16:30(GMT+02:00).
The pictures are taken in sequence, they should be covering about about 1 minute interval from 16:27 to 16:28.

The pictures are not mine, the person who shot them doesn't want to reveal his exact location. I asked him and he gave his permission to "show them to whoever 'experts' you want and play with them as much as you want". (I'll try to ask him for a proper release to public domain, if they are important.)

So, here are the pictures he published himself. Please note that they might be with degraded quality by the site he used.

pic_006


pic_007


pic_008


pic_009


pic_010


pic_011


pic_012


I asked the photographer to provide the originals and he gave me this URL onedrive.live.com/file.rar .
These should contain more metadata and exact timing.

Now, he claims that he didn't saw any flying object. That the trail have been condensed and didn't move, until it started to fall apart, as is evident from the last photos.


I'm not very skilled with photo manipulation, but I have managed to cut segments containing the trail, make them into layers, set the background to semi-transparent and overlay them so the trail fits. Even from the last 3 pictures it is evident that the trail parts were moving in different directions and with different speeds. I managed to resize and fit segments from the first panoramic pictures and they followed the same pattern.

Using my eyes only and making few assumptions, I would say that the time this trail have been straight line is about 3-4 times the time between first and last picture, so 3-5 minutes.

I hope you might find more useful information in the photo, despite the lack of landmarks. There is only visible part of a poplar tree, 5-10 meters high.
I also haven't examined the originals yet. I might edit this post if there is relevant information.
 
I've stumbled upon a couple of recent photographs that may help to explain the origin of these squiggly thin trails.

Here is a close-up of rather unusual contrail taken in Washington state on August 9, 2014

Source

and a crop from a wide angle shot of it taken a few seconds earlier:


Source

In the beginning it is a typical double-stranded hybrid contrail, but at the end it breaks down in an asymmetric way with one of the strands waning. Normally, the two strands destroy each other because of Crow instability, so what makes this contrail different? I hypothesise that the two counter rotating wingtip vortices, forming the hybrid contrail strands, interact not only between themselves, but also with an invisible rotor of air, as in #4. The air turbulence would amplify the vortex with the same direction of rotation and curtail the vortex of opposite rotation. I guess that, in the case of a sufficiently strong air turbulence, the second hybrid contrail strand may not form at all.
 
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I've stumbled upon a couple of recent photographs that may help to explain the origin of these squiggly thin trails.

Here is a close-up of rather unusual contrail taken in Washington state on August 9, 2014
View attachment 8594


and a crop from a wide angle shot of it taken a few seconds earlier:
View attachment 8593


In the beginning it is a typical double-stranded hybrid contrail, but at the end it breaks down in an asymmetric way with one of the strands waning. Normally, the two strands destroy each other because of Crow instability, so what makes this contrail different? I hypothesise that the two counter rotating wingtip vortices, forming the hybrid contrail strands, interact not only between themselves, but also with an invisible rotor of air, as in #4. The air turbulence would amplify the vortex with the same direction of rotation and curtail the vortex of opposite rotation. I guess that, in the case of a sufficiently strong air turbulence, the second hybrid contrail strand may not form at all.


I have been looking for some computational results that can support my hypothesis above and found the following link:

http://archive.nrc-cnrc.gc.ca/eng/news/iar/2002/01/30/crash-theory.html

Mokry's analysis of vortex behaviour shows that one of the pair of vortices may not decay initially, but may be strengthened by the wind, contrary to current expectation.
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Screen shot 2014-08-25 at 20.12.00.png

If this theory, predicting the aircraft vortices decouple at certain conditions with one of them getting stronger, is correct, then it seems possible that this vortex can produce a single hybrid contrail strand, which, in absence of the Crow instability effect, would persist for longer time.
 
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Actually, all this pictures are from the Netherlands and all but one are of the same contrail. The last image actually is taken in South Rotterdam, but Google (Chrome) has translated non-capitalised 'rotterdam zuid' as 'london' :p
Another example of the Lorem Ipsum effect: https://www.metabunk.org/threads/lorem-ipsum-of-good-evil-google-china.4248/
 
An update from Wim via email:


But there's more news! Today, Patrick FERRYN, head of COBEPS (http://www.cobeps.org/fr/cobeps.html) and also on the EuroUfoNet list, sent me a new Belgian report, this one from the city of Liège in the French speaking part of the country. I translate from a message the witness addressed to COBEPS correspondent Michel DE NEVE:

"I took two pictures (...). I'm attaching the originals (Canon A70).
They were taken through a window, camera set on 'automatic'. I put myself a bit out of a Sun, I tried to frame as to get a more or less correct shot... The clouds in the background were moving (or forming?) quite quickly. The phenomenon was not visible for a long time. Just long enough for me to to take the picture (Liège, at about 100 meters north of the choir of the Saint-Martin's Church)."

That's all I have about this new incident, plus the fact that the date was March 5, 2015. (according to the EXIF data, the times the photos were taken were 12:19:53 and 12:20:11 local).

Considering that all cases collected so far involve accidental witnesses, it is becoming increasingly strange that all reports date from after 2002. If I'm not mistaken, the earliest one we have was the one from Malderen, Belgium, March 3, 2002 (BTW, did I sent you that one?!). I've been trying to find similar reports from the past, but so far no luck.
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Liège-050315-2-IMG_4297.JPG
Liège-050315-1-IMG_4296.JPG
Photos obtained via Wim van Utrecht of CAELESTIA, who himself received them from Patrick FERRYN of COBEPS (Belgian Committee for the Study of Aerospace Phenomena


Here's a closeup:


Quite a strikingly bright and clean squiggly line. With the contrast enhanced you can see it's very different to the lower clouds - and to what looks like an aged contrail.
 
Photos obtained via Wim van Utrecht of CAELESTIA, who himself received them from Patrick FERRYN of COBEPS (Belgian Committee for the Study of Aerospace Phenomena
Considering that all cases collected so far involve accidental witnesses, it is becoming increasingly strange that all reports date from after 2002.
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In my list, there is one case from 2000, one from 2001 and one from 2002 (Appendix 1):
https://www.metabunk.org/threads/si...y-hybrid-contrails-the-rook-instability.4539/

I think the lack of earlier reports is probably due to digital photography being in its infant stage at the time.

Unfortunately, I do not have Premium FR24 to play back March 5th and to see what plane could have left this trail.
 
Sorry my text seems to have disappeared.

The photo was taken on Sunday 12th at approx 10:20 BST and facing South. The photo was taken from 51.5782°N, 1.1343°W I stopped the FR24 plot over the location.

How do I post the EXIF data? The time/date on the picture will be incorrect as I saw the trail, rushed inside to get the camera and then put the batteries in. I didn't set the time/date.

OK, I found an on-line EXIF viewer.
Make
FUJIFILM
Model
FinePix S9600
Aperture
6.4
Exposure Time
1/400 (0.0025 sec)
Focal Length
21.6 mm
Flash
Off, Did not fire
File Size
7.3 kB
File Type
JPEG
MIME Type
image/jpeg
Image Width
448
Image Height
336
Encoding Process
Baseline DCT, Huffman coding
Bits Per Sample
8
Color Components
3
X Resolution
72
Y Resolution
72
Software
Digital Camera FinePix S9600 Ver1.00
YCbCr Sub Sampling
YCbCr4:2:0 (2 2)
YCbCr Positioning
Co-sited
Exposure Program
Program AE
Date and Time (Original)
2006:01:01 00:00:23
Max Aperture Value
2.8
Metering Mode
Multi-segment
Light Source
Unknown
Color Space
sRGB
Sensing Method
One-chip color area
Custom Rendered
Normal
Exposure Mode
Auto
White Balance
Auto
Scene Capture Type
Standard
Contrast
Normal
Saturation
Normal
Sharpness
Normal
Subject Distance Range
Unknown
Quality
NORMAL
Sequence Number
N/A
F Number
6.4
Exposure Compensation
N/A
Focus Mode
Auto
ISO
80
Color Mode
Standard
 
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I have an image of one of these from 2006 which I observed about an hour after the Transit of Mercury - images here http://www.johnmurrell.org.uk/Transit of Mercury Turbulence V2/index.html near the bottom of the page. The other images show a 'clear air' version of something similar crossing the Sun about an hour earlier. You can see the refraction of the sunlight and the distortion caused by the 'turbulance'. There is an animated gif linked to this page or else just step through the individual images.

John Murrell
 
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