It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Thank you.
Some features of ATS will be disabled while you continue to use an ad-blocker.
Originally posted by TreehouseIndustries
[example: 6 white planes fly over Christchurch within 15 - 20 mins of each other west to east (there is no flight path, military or otherwise that uses that heading)
Incidentally, there was also an aircraft flying in perfect circles from about 7:00 to 12:00 UTC, centered on approximately The Wash, if anyone knows what it would have been, I'd be interested to know. And no, even that 'highly suspicious' pattern left very little persistent contrails.
Apparently it was two aircraft, LX-N90453 N.A.T.O E-3A Sentry, and ZH102 Royal Air Force E-3D Sentry (according to the EMA Spotters group).
Originally posted by ProudBird
Here:
Aircraft Circling North of London
Ah, this.......Down the page, a post by member "TCASAlert" explains it:
Apparently it was two aircraft, LX-N90453 N.A.T.O E-3A Sentry, and ZH102 Royal Air Force E-3D Sentry (according to the EMA Spotters group).
It must surely, by now, be abundantly clear that anyone who has regularly contributed to this board over a time that STILL uses the "contrails don't persist" line are deliberately trolling. Even the Chemtrailers-in-chief are now accepting that trying to deny that contrails exist just makes their position look stupid, but some on here still cling to it.
Originally posted by waynos
Wow, so many questions. I will try my best to address them for you
Originally posted by jackmac
Yes. I have a thought, a question even...
Are you saying that these 'cirrus' clouds would have formed anyway? If so please indicate exactly how you could know that. Thanks
It is an argument I have seen on here, which is why I raised it as an alternative view, but I don't completely subscribe to it ...contrails can themselves promote the creation of cirrus... What many see as the trail 'spreading', ... is the creation of cirrus cloud from the moisture in the atmosphere, but which was triggered by the presence of the contrail ...Therefore I'm not convinced you can definitively say the cirrus would have formed anyway, only that there is a reasonable probability it would. No more than that.
'Proof' is a very strong word. Are you sure? The 'model of operation' could be very simple, could it not?
By this I was saying that I consider it proven beyond reasonable doubt to me. I don't understand why you feel the model of operation would be simple? I don't see how anything that requires the complicity of the pilots, engineers, loadmasters, suppliers, purchases, ATC, flightplanners and the other myriad of people responsible for aircraft operations, spread over several continents and involving governments and lots of privately owned companies could ever be simple?
'The technology exists...' The technology to do what?
The technology to spray various substances from aircraft.
'Knowing the science kills it stone dead' - and what science is that?
...the science that proves that the central assertions that contrails cannot linger and spread out
... it is not credible that this level of competence could be...sustained, for so long. ...not one single person...has ever blown the whistle
I think you need to look at this again.
Why? I am not conceding the trails are odd, only noting that people see them as such, which they do rightly or wrongly.
A two sided debate, if conducted honestly is a great thing.
....and this when the UK was under very dry conditions, very very dry. Appleman would say: NO contrails....
The RUC model data are representations of the complete 3-dimensional structure of wind, temperature, and humidity over the USA at a resolution of 25 mb and 40 km. The horizontal resolution has been degraded to 1° latitude x 1° longitude to facilitate the computations. Because they are based on a sparse number of actual in situ (balloon sonde) data taken every 12 hours and satellite measurements, the RUC data are not a perfect representation of the various meteorological parameters, especially water vapor. The model humidity at upper levels of the atmosphere is often too low, reflecting the current biases known to exist in our measurement system. Persistent contrails require a relative humidity with respect to ice (RHI) that exceeds 100%. We know that contrails are sometimes observed in areas where estimates of the RHI are less than 100%. The existence of contrails in those locations highlights the "dry-bias" in the humidity fields.
Because the input data do not perfectly characterize the meteorological conditions, the diagnoses of persistent contrail conditions are only estimates and will not detect all of the areas where persistent contrails will form and may also add areas of formation that do not exist.
Originally posted by ProudBird
reply to post by jackmac
Um:
....and this when the UK was under very dry conditions, very very dry. Appleman would say: NO contrails....
Did you mean "very very dry" conditions on the surface? And, Appleman has been superseded. He first devised and published that chart in 1953.
Yes, modern high bypass turbofan engines (which did not exist in the 1950s) produce more contrails in a wider range of atmospheric conditions. Of more persistence.
NASA have a contrail forecast page (for the ConUS) that is indicating based on historical RUC (Rapid Update Cycle) data collected over several years' time.
The relative humidity was very low on the whole - 43 being the highest, 3 the lowest and 21 average; dew points were distant from air temperatures; not one single reading, at any altitude, over all the miles those three soundings covered would have supported a 'yes' to the mass cirrus formation which took place...
And why exactly do these turbofan engines produce more persistent contrails? In your own words please
Abstract: This report documents the results of a study requested by the Strategic
Air Command Deputy Chief of Staff for OpFrations (SAC/DO) to update previous
contrail forecasting research done by Herbert Appieman for HQ Air Weather Service in
1953. Advancements in aircraft power plants, especially the development of bypass
turbofan engines, made the new study necessary. This attempt to update and improve
current contrail forecascing methods was performed by the SAC Directorate of Weather
SAC/DOW). It describes the development of new contrail forecast algorithms for) .
several types of engii.es used in high-flying aircraft. It also provides contrail
forecasting rules that correlate synoptic-scale upward vertical motion with contrail
formation. The results indicate significant improvement in contrail forecasting accuracy
over the Appleman technique now in use at the Air Force Global Weather Central.
On contrails creating cirrus:..............................Would you concur?
Why would pilots necessarily need to know? Who needs to know what? All these people/companies you cite could be easily by-passed with a bit of thought. I invite you to imagine how you might do such a thing, if you were charged with designing 'the system', as it were. How would you go about designing it?
Originally posted by Aloysius the Gaul
Originally posted by TreehouseIndustries
[example: 6 white planes fly over Christchurch within 15 - 20 mins of each other west to east (there is no flight path, military or otherwise that uses that heading)
There are several such airways - below is a scan & awkward rotation of the air routes around Christchurch - the city is the nexus at the bottom right and the coastline - the Estuary & Lyttleton Harbour are in light green also at bottom right.
The map is oriented north-south - it was a bit awkward to get it that way sorry, so some detail has been lost, but there are clearly airways going both east and west.
I have no idea how often they are used - but they are there.
-
This is from "Upper South Island" route map in Vol 2 of the NZ AIP's, effective until 17 November 2011...which yes I know means it is out of date but it's the only one I have access to atmedit on 16-1-2012 by Aloysius the Gaul because: (no reason given)
.....I cannot find any flight paths that would take flights directly over Christchurch with an west east heading at high altitude without landing. specifically I am referring to the 23rd of December in Christchurch, where i witnessed multiple flights the aforementioned heading (west to east)
Originally posted by ProudBird
reply to post by TreehouseIndustries
.....I cannot find any flight paths that would take flights directly over Christchurch with an west east heading at high altitude without landing. specifically I am referring to the 23rd of December in Christchurch, where i witnessed multiple flights the aforementioned heading (west to east)
Have you considered international flights from Australia to South America? Qantas operates Sydney to Buenos Aires and Santiago, for example. These, depending on the way the Airspace is set up, would preferably fly on a Great Circle, but that isn't always feasible.....so they may pass over, or just North of Christchurch....if North, then prevailing winds can blow contrails in a Southerly direction, if that's the way the winds are blowing, etc.
Also, there are other airlines based in South American countries that can operate to/from Sydney, or possible elsewhere in Australia.
Go find yourself a globe ( I just looked at some maps, and also my globe).....on the globe, since it's a sphere, the easiest way to "eyeball" a Great Circle path (shortest straight-line distance on a sphere) is with a piece of string, held at each city (Sydney and Buenos Aires, for instance). You will find it passes very close to Christchurch.
but how many times a day are quantas flying that route? 4 flights within 2 hours?
Originally posted by ProudBird
reply to post by jackmac
No, not "500 feet lower" for the more prevalent persistent contrails.
The relative humidity was very low on the whole - 43 being the highest, 3 the lowest and 21 average; dew points were distant from air temperatures; not one single reading, at any altitude, over all the miles those three soundings covered would have supported a 'yes' to the mass cirrus formation which took place...
43% is damn high.....so is 21%!!
You mention dew point spread.... exhibited "faith" in Appleman. Well, the dew point spread is going to tell you the RH....but, Appleman graphs according to temperature and pressure altitude, to estimate ("predict") conditions for contrails.
Appleman Chart
Perhaps if you had included the radiosonde date with temps too, your post above could have more veracity.
And why exactly do these turbofan engines produce more persistent contrails? In your own words please
Sigh.....I have written this many times, here (other threads). The goal of engine manufacturers, in the modern era of very high fuel costs, combined with ,,,decibel reductions ,,,imposed ,,,through most of the World ---
(***Stage 3 noise limits....later regulations stipulate more restrictive Stage 4 standards)
---these result in designs that strive to ever increase fuel burn efficiency, and seek to "mask" the sound of the engine, and its exhaust, as much as possible.
The increased fuel burn rates have led to ever lower temperatures of the combustion exhaust gases, after the exit the engine (not internally.....burning hotter, up to the materials' ability, is more efficient --- provides more power per pound of fuel --- internally). Then, the already present column of ambient air that is produced by the large N1 fan, which also provides the majority of a modern engines thrust, mixes and "buffers" the hotter central core of exhaust gases. The cylindrical column of cooler air acts also as a sound "baffle", for the noise suppression.
[***]::Stage 3 and 4 noise limits: The link below is to the U.S. FAA regulations, but they are generally identical to the ICAO standards ---
PART 36—NOISE STANDARDS: AIRCRAFT TYPE AND AIRWORTHINESS CERTIFICATION
Jump to Paragraph 36.103
"Stage 3" dates back to 1975, when jet engine noise became a "hot topic", especially in the USA. Then, there were restrictions based on the Airport Authority (and complaints from annoyed citizens....know the term "NIMBY"?). Leading to, depending on the airport, and surrounding communities of citizens, various restriction for airplane types, and operating hours, routings, etc. See the airport in Orange County, California, (KSNA) for an example of "community activism" gone mad. Wealthy residents = Squeaky wheel getting "oiled"....even in some aspects, to the detriment of safety.
But, that was a description, nutshell, in "my words" of current modern high bypass turbofans, and their sustained and increasing proclivity to make contrails.
Originally posted by waynos
reply to post by jackmac
On contrails creating cirrus:..............................Would you concur?
I did post that viewpoint as an opposing view with a request for thoughts, that is not me using it as an argument, its siimply looking at the argument from both extremes.
Cirrus frequently forms without aircraft being present....while ...it would have formed... is a possibility, it is equally possible it ... formed right there, or even may have begun to before any aircraft passed through. The point is that there is no definitive answer to that particular question as far as I can see and your position is as flawed as the original counter argument I was asking about. I cannot think of any possibility that cirrus formation would be due to aircraft emissions *alone*. This is not possible.
edit on 17-1-2012 by waynos because: (no reason given)
Originally posted by waynos
reply to post by jackmac
Why would pilots necessarily need to know? Who needs to know what? All these people/companies you cite could be easily by-passed with a bit of thought. I invite you to imagine how you might do such a thing, if you were charged with designing 'the system', as it were. How would you go about designing it?
Sorry, but to me, that simply demonstrates a lack of understanding of how an aircraft operates. You CANNOT bypass the pilot, he needs to know everything that's on the plane and everything that is happening with the plane, full stop, no exception. This also applies to all the others I mentioned too, the supposition is they could be bypassed is naive.
edit on 17-1-2012 by waynos because: (no reason given)
Originally posted by waynos
reply to post by jackmac
My personal incredulity is supported by experience and learning.... If my view is shown to be wrong, I will change it. So far it has not been
edit on 17-1-2012 by waynos because: (no reason given)
The reason for their formation is very often and very obviously attributable to aircraft jet emissions, and to that alone.