Photos of Planes and Contrails (That you took yourself)

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?
 

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

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.
 
But 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.

The A380 has condensations above the engines:



 
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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.
 
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.

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march 2nd 2013 010.JPGmarch 2nd 2013 013.JPGF-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 .
 
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.jpg
Bell Griffin HAR2 (Bell 412EP Varient) RAF 84 Squadron ZJ706

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

Lofou Fire June 2013_03.jpg
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.jpg
Kamov KA-32AO Pankh RA-31571

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

Vouni Fire Aug 2012_03.jpg
Air Tractor Inc AT-802, Cypriot Department of Forests FD-1
 
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.JPGIMG_6150.JPGIMG_6179.JPGIMG_6154.JPG
 
Slats out in a hard turn...very interesting. Do you think this was automatic or intentional based on speed?

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.




 
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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.




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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Final batch from my archives.

Swiss F/A-18 Hornet





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





RAF Typhoon





RAF Typhoon





RAF Typhoon - Fuel vent from fin.





French Air Force Rafale





RAF Typhoon





RAF Red Arrows





RAF Tornado


 
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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.

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.

The Bf 109’s automatic leading-edge slats popped out of the wing when the Bf 109 was flown at slow speed – making a clanging noise so loud that pilots could hear it above the roar of the engine. The slats increased lift and drag but were not for the faint of heart. Oberleutnant Erwin Leykauf said, ‘For us, the more experienced pilots, real manoeuvring only started when the slats were out.’1 Less experienced pilots could put a Bf 109 into a stall and spin when the slats deployed on one wing and not the other in a tight turn. When slats deployed unevenly in tight turns, they would disrupt the airflow, causing the ailerons to ‘snatch’ enough to shake a Bf 109, spoiling the pilot’s aim.
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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.....
 
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.
 
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.
 
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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".
 
A few more that escaped my final trawl.


Italian Air Force C-27J Spartan





Privately owned Hawker Hunter venting fuel after take-off.





Hungarian Air Force Saab Gripen venting fuel that ignites.


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

Cheers
Tom
 
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.

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".
 


Photograph Credit: Ken Lee, a spotter for the National Weather Service in Sacramento. Shared by NWS Sacramento.
 
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OH NO!!! They are spraying chemtrails on the moon!

On the way to the moon:



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

Here it was better:



And 738 from SunExpress:



Winglet with moon over the Mediterranean:

 
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(Insert image doesn't seem to be working or I'm doing it wrong)

Flickr imagery requires additional steps.

1) Under the Flickr image you wish to insert here, click on the "more ways to share" button
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_2106 by Mr Thumpy, on Flickr
 
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