[Grewlybreekly]

Okay first of all this perception that contrail's only last for a few hours at most is incorrect!

Acupunture, in the conditions you describe the photo's are taken (perfectly clear sky, no wind) is probably the best time for a contrail to remain visible for the longest period of time. During this time the ice particles will slowly spread out and create what is essentially a Cirrus cloud. If you live near a busy flight path, dozen's of flight's will occur overhead. Live in just the right spot and flight's will cross each other at 90 degree angle's. Now to keep all the planes safe they fly slightly different lanes, obviously to prevent mid air collision's. A cross work pattern is usually the result, if you could see flight path's in 3d you would also see the altitudes are also different. So this is not a sign of a test pattern. Infact a search pattern would be better imployed if you wanted to do what you are implying, and that is usually to run up and back just like the que pattern's you find at airport's, amusement ride's etc.

Cirrus cloud has two effect's depending on the size of the ice particles. Small ice particles reflect the sun's rays reducing the heat absorbed by the Earth. Larger ice particles do the opposite and the Earth becomes warmer.

Besides aircraft, what create's Cirrus clouds? Thunderstorm's! The giant thunderheads send moisture high into the atmosphere which then create either small or large ice particles, no one know's why either one or the other is formed but researches are doing their best to find out by watching thunderstorms very closely. Now tell me do you see Cirrus only if a thunderstorm is in the area? No, and that right there tells you that cirrus clouds last for long periods of time if the conditions are favourable.

The implication of all this to us and perhaps a possible reason to experiment with planes creating Cirrus clouds? Well during sept 11 when all the planes in the US where grounded, the average temp for the day nation wide was a couple of degrees hotter. Not a very good statistic to prove anything but it could hold the key to controlling the Earth's environment.

So this leads back to the small versus large ice particles. Scientist's know that smoke from forest fires likely creates more violent thunderstorm's. What they don't know is what the trigger's are to create either one or the other.

So if I was a betting man, I'd say it was much more about creating these ice particle's rather than testing on humans. It is most likely not even military or government backed, a team of international scientist's are currently working on thunderheads and the effect's. They use multiple planes working in unison, so if another team is studying Cirrus clouds I cannot see why they wouldn't do the same thing.

Conspiracy, no. Scientific test, maybe. Deliberate poisoning of humans, very unlikely. High level's of toxin's could be coincidental due to the condition's. I'd be looking more at manufacturing plant's if you find unusually high reading's of toxin's in the air.

Lastly that the tv show's you posted look like they just wanted to fill in some space with a fear mongering story to boost rating's.