Aerosol Spraying over Dublin

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kilo delta
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Post by kilo delta »

vanman wrote:Oh dear, not the chemtrail conspiracy. I don't think it belongs on this forum, Ken. There's a conspiracy forum over on boards.ie. Much better there.

KiloDelta, KenDoyle, hmm bit of a concidence that you both have the same initials. If that's a shade account KD, it's a bit obvious if you want to start a wind up.

As for the chemtrails over Dublin thing. Well they were contrails. They were lingering all over the country on saturday. They reason is probably something to do with the atmospheric conditions over the weekend. Here's a sensible explanation for contrails which also mentions lingering contrails and how they spread out. Forget all the chemical nonsense. http://students.ou.edu/J/Thomas.A.Jones-1/contrail.html

I have been observing ordinary
contrails since I was a small boy and this is quite different.
That's because A. there's more air traffic around now and B. high bypass turbo fan engines produce stronger chemtr........sorry contrails :roll:

So put away you tinfoil hat Ken or Kilo or you're going to look foolish.


I can assure that I've nothing to do with the origins of this thread. READ my post and you'll see that I state quite categorically that I believe that the Chemtrail Phenomena is BS.
Kilo Delta = my name (The details of which are privy to Mark Dwyers)
You may contact him to confirm this if you so wish...I'm sure that he can provide my ip details too.
:roll:

Alan Dunne
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Post by Alan Dunne »

The plane looked approximately like this:

http://i9.photobucket.com/albums/a94/Wt ... 147218.jpg

It did not appear like an Aer Lingus or a Ryanair type plane, nor was it a jet.

It had a chunky appearance. It kinda had a "military type look".......but white.

I don't know how many engines it had?
Last edited by Alan Dunne on Mon May 11, 2009 7:53 pm, edited 2 times in total.

kendoyle
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Post by kendoyle »

I did see one very low flying craft yesterday but it wasn't emmiting anything.I would describe it as a sort of a sqaut looking plane with 4 engines or fuel tanks.It was a jet not a prop and smaller than a passenger plane but still big n chunky looking...colouring was white.

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Post by captain slow »

This is the best thread ever.

Jet engines burn fuel of course they emit 'chemicals'afterwards but nothing different for the last 50 years. The same as car engines burn fuel which emit chemicals and when you walk down a busy street you inhale more dioxins than if you lived beside 10 incineration plants.

As a novice, I would've imagined that flight paths that cross would have to be at least several hundred feet apart. As you may be able to tell some of these formations, they're actually quite low and it was clear from looking at the cross section part through the binoculars that they were at the same level.


You wouldnt believe the number of people who think planes pass really really close to each when in fact they dont all because they view them from the ground and get confused by the visual illusions caused by slant range/angle and so on. They pass at the leaglly acceptable 1000ft seperation but from the ground it appears that they are in effect at the same altitude. You wouldnt believe the questions i get when asked by myfriends to explain what looks so close above their heads. Mates in ATC say the huge volumes of calls on fine clear days with people reporting near misses above their heads when in fact their is nothing close or near about them at all.



Knowing flight paths as you do......what are the chances of 4 separate flight paths cris-crossing at the same level........ side by side, all used within the space of an hour?


The chances are that having just 4 seperate planes/flight paths cross in a busy spot like dub is almost 100% certain. In fact you could and do have 30+ aircraft cross the same spot often in different directions in 1 hour. Now i accept that your not a dummy but you got to be open to the logical and factual explanation as much as the 'unusual' explanation.

I dont live near dub but my house is near 2 major airways in the sky that cross at more or less right angles. I have flown these routes at varying altitudes from 17000ft to 37000ft so i know what they look like from the air and from the ground.At certain times of the day especially early mornin they are quite busy. I have had aircraft pass under and above me at 1000ft and while this perfectly safe and looks fine when you are up there from the ground there is no way of knowing how far apart the two airplanes are. Hence many people think they are at the same height when in fact they are not. I have myself sometimes stopped my car and looked at two planes crossing way above me. To my eye they look to be at exactly the same height but the crews onboard and atc ensure they are not. They do pass . My point is things look so much different from the ground comapred to the reality in the air.

As for the photos im afraid they look like bog standard contrails.

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Post by Alan Dunne »

The chances are that having just 4 seperate planes/flight paths cross in a busy spot like dub is almost 100% certain.


4 flighpaths, side by side......in X-like formation? I'd like to see how that looks from an air traffic control point of view.

Through the binoculars it was clear that the criss-crossing trails physically touched. They were quite low; I can assure you they where not 37,000 ft up. Whatever about appearance from the ground using the naked eye at those kinds of heights, this was low and through binoculars you could make out significant detail at the "criss-cross" section.

We've all seen planes crossing over each other, infact most of us have probably been on a plane and seen a plane pass what appears to be closely. That was not the case here.

Like I said, this plane did not look like a passenger plane going to Ibiza, it was distinct enough to recognise that it was the same plane making the trails (or type of plane if it was more than one).

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Post by Flyer1 »

4 flighpaths, side by side......in X-like formation? I'd like to see how that looks from an air traffic control point of view.


Probably like 4 X's i'd imagine. You just got what is a reasonable explanation from an experienced aviator, don't be worrying now.

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Post by captain slow »

Just off the top of my head there are at least 11 routes that cross over or around dublin and i can tell you having 4 planes cross at the same altitude within a very close time frame is not thatt unusual at all...thats why the lads in atc are there.

There are multiple standard routes into and out of dub many of which means that out and inbound planes cross over and under each depending on phase of flight.Ask any pilot who flies into and out of dub and they will tell you the same thing that the outbound flight climb and cross over the descending inbound flights. If the dont have the required vertical seperation the atc will direct one behind the other so they miss but they will be at the same height.

what you saw was in the no way unusual at all (believe it or not thats up to you) just that you are misinterpreting what you saw. Simples.

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Post by Alan Dunne »

His explanation involved paths crossing thousands of feet apart and many passenger planes........that's not what we witnessed

Also, there appeared to be one particular plane in the sky yesterday capable of causing trails that lasted hours. The rest dissappeared almost instantly.

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Post by Alan Dunne »

Is there a website with plane flightpaths for Dublin perchance?

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Post by mark »

Alan Dunne,

Why are you using a username different to the name you supplied on the registraton page when signing up to the forum? It kind of undermines everything you have said so far....


And for the record, Kilo Delta is not associated with Ken Doyle...

Regards,
Mark

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Post by Alan Dunne »

Btw, if it is so common to have four large X's in the sky side by side at the same alt., why didn't someone say that at the outset?

Several hours ago it was so "impausible"........now it's "routine"

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Post by Alan Dunne »

My name is irrelevant Mark.

This thread is either populated by the chidren of 60's hippes or........Nanolight, Vanman, Captain Slow, Flyer 1, Bump and On the Numbers...........are not their real names. Funnily enough, that doesn't matter either.

Or do you just prefer your non-mates to reveal themselves?

Slightly irresponsible moderating there Mark. Normally a moderator wouldn't utter a jot about peoples identities............unless it's on an inbred site.
Last edited by Alan Dunne on Mon May 11, 2009 9:20 pm, edited 1 time in total.

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Post by alphaLaura »

All those photos show very standard contrail formations. On Sunday, there was a weak warm front which decayed over the country and the higher, milky glaze of cloud is a signature of this. Contrails which are set against the backdrop of this milky sky can often cause depth perception difficulties. It is quite normal for aircraft to cross over and under each other on different headings tracking navaids but they are usually separated by thousands of feet acording to ATC. I would also suggest that there is a definite vertical and horizontal spreading movement of contrails once they are created in the atmosphere. Contrails can be exceptional stable (ie - long living) if the relative humidity at a certain altitude is >40% with a temperature of at most -39 Celsius. They can dissipate but will take hours to do so.

http://www-pm.larc.nasa.gov/sass/pub/journals/Minnis.etal.JClim.04.pdf

Alan - I imagine that what you saw is 4 different aircraft of similar type, all flying at nearby altitudes on reciprocal headings. (All perfectly legitimate behaviour for Air Traffic Service controlled flights.) These altitude ranges had the correct conditions for stable contrails which spread during the day into a more disperse form to create the illusion of same-altitude flight paths. (Vertical spreading of contrails has also been observed over heights of the order of ~100 metres: http://www.pa.op.dlr.de/tac/2006/proceedings/267-308.pdf - see page 295)

One final note: The last photo taken at twilight with the pink/purple hue is easily explained by the physical law which governs the reason we perceive the sky as blue. This is due to Rayleigh scattering, which explains how the higher frequencies of electromagnetic radiation from the sun (ie - blue colours) are absorbed more than the lower frequencies (ie - red colours). When the sun is setting, the angle of incidence of its light on the Earths surface turns towards a grazing angle which produces strange colouring effects when viewed through milky skies such as Sunday's one.
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Alan Dunne
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Post by Alan Dunne »

These altitude ranges had the correct conditions for stable contrails which spread during the day into a more disperse form to create the illusion of same-altitude flight paths.


All four where created in about 1 hour.

For example we were looking at the last two, as they where being created. We did not wait for them to "spread during the day"


It is quite normal for aircraft to cross over and under each other on different headings tracking navaids but they are usually separated by thousands of feet acording to ATC.


I'm not doubting it is, but again that's not remptely close to what we watched occuring
Last edited by Alan Dunne on Mon May 11, 2009 9:31 pm, edited 1 time in total.

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Post by mark »

Alan Dunne wrote:My name is irrelevant Mark.


I disagree, you only registered today and come on here calling people nerds and dweebs. As a moderator, I think your idenity is very important espcially as your username is shared with another aviator I know.

As for Nanolight, Vanman, Captain Slow, Flyer 1, Bump and On the Numbers, they may be not their real name but I know each and everyone of them and have huge respect for them all.

You have been given perfectly good explanations for all your questions but you persist. There are many skilled pilots who have given you perfectly logical answers, where are you going with this argument?

Regards,
Mark

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