Sequence of Aerodynamic Contrails, Gap, Exhaust contrails. At 25,000ft over the UK

Trailblazer

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Staff member
This one caught my eye on a bike ride this morning. As you can hopefully tell from the phone photo it appears to be a short section of aerodynamic trail, then a short gap followed by engine contrails.

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What was surprising is that the plane was only just over 25,000 feet.

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Both the aerodynamic and engine contrails persisted for quite a while.

There's quite a deep low pressure over the UK at the moment with relatively cold air, -55C at 300mb

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Planes at higher altitudes were mostly leaving very short trails, and the RH forecast at 300mb was very low, so there must have been quite a shallow layer of cold and humid air.

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(My location is about 35 miles west-southwest of London)
 
This one caught my eye on a bike ride this morning. As you can hopefully tell from the phone photo it appears to be a short section of aerodynamic trail, then a short gap followed by engine contrails.

Just annotating that, as it's not clear from your description which is which
 
The plane appears to be climbing fairly rapidly, getting up to 35,000 feet before it hit the channel. Perhaps of slight note is that it was two hours late, and sometimes they go a bit faster to try to make up time (at least that's what they tell you).



Rapid climb means higher thrust, so more water content in the exhaust, so exhaust contrail starting at a slightly lower altitude.

I've seen similar transitions here, the San Francisco traffic is climbing past 24,000 feet over my house, but I've not seen a gap this short.
 
Curiously, I've seen something similar today while working in my garden. I spotted a distant thick trail with a couple of short gaps that looked like an aerodynamic contrail. Before I decided to fetch my camera, the trail stopped and then reappeared as a short exhaust contrail. The plane also changed direction at about the same time heading closer toward me. I have identified it as SN2063 from Brussels. It was still climbing up from 25,000 ft over the North Sea:
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I did not bother to take the plane's picture when it come closer. There were more clouds overhead than in the southeast part of the sky.
 
A couple more pics. This is the short bit of aerodynamic contrail a couple of minutes later. (The gap grew a bit but you can still see the exhaust contrail at the top of the photo)

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And the exhaust contrail another minute or so later as the plane headed off to the east. It's actually above that thin cloud layer and visible through it.

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Bristol to Innsbruck on easyJet, that'll be packed full of people going skiing. I'm not jealous at all...
 
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