Contrail or cloud?

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celica_tommo
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Contrail or cloud?

Unread post by celica_tommo »

saw this last night in Auckland... it stuck around for at least an hour

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NZstorm
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Unread post by NZstorm »

celica

The only cloud cover(moisture layer) over Auckland last night was an overcast layer of thin Cirrostratus at about 9000m. Winds at that level were SW at 25kts.

The only possible cause for such a line through the cloud (other than a hoax???) would be an aircraft passing through our region at cruising level and then doing a u-turn.
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Storm Struck
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Unread post by Storm Struck »

Could be a smoke ring this depends on where you took this photo it may be an area of smoke mixed with smog on the edge of the Auckland city.
Sometimes if winds are blocked in many areas or variable one day winds can overlap causing these rings.
It happend in New York once in the late 1900's.
Welcome there I see you are new.
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celica_tommo
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Unread post by celica_tommo »

nope, this is not a hoax... and yeah I'm new, this'll most likely be the only time I'll visit this site as i dont have much of an interest in weather generally

I've got plenty more pictures and several other people that saw it too

It was last night at about 9pm i think looking from mt wellington looking very roughly eastwards over panmure

Thats not really a U turn though is it... I would'nt want to be in the Boeing 747 making that manouver... more of a 360 degree turn

Just thought I'd post this up because between us we couldnt decide what the cause of it would be
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Unread post by spwill »

Thanks Celica for the Photo.

It is either Aliens from another World trying to send us a message or it has been created by Aircraft. The sky area over East Auckland and beyond is where Aircraft circle for landing or taking off from Auckland Airport.
North Easterlies last night would have had Australia bound Aircraft taking off into the Eastern sky and then doing a sharp U turn to head West out over the Tasman.
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NZstorm
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Unread post by NZstorm »

Unfortunately the photo is not that clear, due to the time of day.

Just looking at the NZWP sounding the upper air was dry apart from a moist layer at 9000m mark, where there was a layer of cirrostratus, hence, I don't see this as being a manuoevre out of the airport. :)
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Unread post by NZ Thunderstorm Soc »

celica_tommo wrote:nope, this is not a hoax... and yeah I'm new, this'll most likely be the only time I'll visit this site as i dont have much of an interest in weather generally

I've got plenty more pictures and several other people that saw it too

It was last night at about 9pm i think looking from mt wellington looking very roughly eastwards over panmure

Thats not really a U turn though is it... I would'nt want to be in the Boeing 747 making that manouver... more of a 360 degree turn

Just thought I'd post this up because between us we couldnt decide what the cause of it would be
Hi Celia
My thought is to send it to someone in NAZA in the USA
Could be a foreign body/something from outer space.
I don't think it is weather related.

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Unread post by spwill »

NZstorm, I think the cloud layer last night must have been much lower than 9000m.
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NZstorm
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Unread post by NZstorm »

NZstorm, I think the cloud layer last night must have been much lower than 9000m
The only cloud in the sky yesterday evening was cirrostratus and the soundings are quite accurate at detecting the heights of such moisture lasyers. The moisture actually starts around 8400m.

As for the possibility of such high level u-turns, yes aircraft may turn sharply like this.

The fact that the phenomena lasted an hour indicates to me it is high level
and this ties in with our observation of high level moisture.
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Unread post by Willoughby »

I could never see a 747 take a turn like that, I think it's just the sunlight playing tricks with the high cloud.
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NZstorm
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Unread post by NZstorm »

Maybe it wasn't a 747. It could have neen a military aircraft on training from Australia. Who knows. But we can be safe in the belief it was a plane unless there is life on mars after all. :D

I have seen contrails do a sharp turn.
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Unread post by celica_tommo »

You would think someone would have heard a plane that close and able to make a turn like that though
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TonyT
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Unread post by TonyT »

Some thoughts. Contrails are easily blown by local winds. So the shape seen in the photo is not necessarily the shape of the flight path of the aircraft. We cant be sure its a plane flying in the CS layer, or in fact flying above, generating a contrail cloud and having a shadow cast on the CS layer below. I have seen this several times. If it is a contrail above the CS then with the time of night it could be some distance away, the shadow angle will be quite large and it may appear rather distorted.

If we assume it is in the CS layer, and the CS is at 8400m as Steven suggests, then if we know where the photo was taken from, where it is looking towards, and can guess the elevation angle of the contrail, then we can triangulate how far away the contrail is, ie its ground position. The way to do this is to go back and stand in the same place you took the photo, estimate the elevation angle of the top and bottom of the contrail (the telegraph poles provide a useful reference in this case) and the angular width of the contrail. The rest is straightforward trigonometry.
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Unread post by Thunder »

Maybe it was a giant cowboy trying to laso Mt Wellington?
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Unread post by C-Nimbus »

Aaron J Wilkinson wrote:Maybe it was a giant cowboy trying to laso Mt Wellington?
my thought is a hair on the lense!!!

:D ;)
celica_tommo
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Unread post by celica_tommo »

I thought it looked like the upside down triangle on one of the telly tubbies heads... tinky winky is it?
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Unread post by Thunder »

Yep that's the one!

Big ass horse shoe funnel?
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Aaron Wilkinson
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Unread post by Area51 »

Hi Everyone

I've just joined and I must say what a wonderful, informative forum it is.
I've been involved with meterology in the past and still hold an active interest in it with my current job working at Auckland Airport.

In answer to the unusual sight over Auckland on Saturday night. It was an Air NZ Boeing 737-300 carrying out a test flight at 35000ft following a major maintenance check in Auckland. Usually these checks take place in Christchurch but a couple of times a year end up being done in Auckland.

Regards
Mike
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Unread post by Storm Struck »

I was hoping it was to do with human life there :shock: So thanks for the truth we have been looking for Area51. :D
Welcome I see you are new to this forum iam sure you will fit in well I know I did any help just ask anyone. ;) .
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Unread post by Fujita Phil »

Such a "normal" explanation from someone with a user name "Area 51" :lol:

Welcome aboard Mike... thanks for the info
There is no such thing as bad weather, just the wrong clothes.
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Unread post by NZ Thunderstorm Soc »

Area51 wrote:Hi Everyone

I've just joined and I must say what a wonderful, informative forum it is.
I've been involved with meterology in the past and still hold an active interest in it with my current job working at Auckland Airport.

In answer to the unusual sight over Auckland on Saturday night. It was an Air NZ Boeing 737-300 carrying out a test flight at 35000ft following a major maintenance check in Auckland. Usually these checks take place in Christchurch but a couple of times a year end up being done in Auckland.

Regards
Mike
Horray, now we can go off to our beds and wonder when the next ENE gales will strike?? :?

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NZstorm
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Unread post by NZstorm »

Mike welcome to the forum and thank you for letting us know who was flying at those alttitudes over Auckland. I thought it must have been training or testing of sorts. :D
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