I wouldn't doubt it. No catalytic converters or any kind of improvement in jet engine like the leaps and bounds of autos.

And..what was it shown after 9/11 when airplanes were grounded..air quality and clarity cleared all over the world?

That's not it Stan. Do the research. Watch the documentary, "What in the World are they Spraying" and it's follow up, "Why are they Spraying it?" It's most likely being done in the name of climate manipulation, which they've had the ability to do since the late 60's. If it's the other reasons, it's downright sinister. Me thinks it's a combination. Be careful, there's a rabbit hole that opens up.

I'm a grower and I do not like the sky that they're making for the past almost 20 years. Most of my garden has been destroyed in 2 dercades, replanted and destroyed again, by artificial weather events (chemtrails). I wish the sole purpose of chemtrailing was just controlling global climate change (chemtrails are known to both cool down and warm up the climate significantly creating storms etc.). It's moire than that. Exotic weapon is one of those reasons: http://chemtrailsplanet.net

Watch the video I provided in the separate link below.

Here is a link that might be useful: What in the world are they spraying?

I've seen contrails made from other planes from the window of a plane before and those contrails were very long lasting and it didn't look like there were any chemicals in them.

The meteorologist in me wants to disprove their existence because contrails can last a very long time in the right environment in the upper atmosphere and sometimes the reason why days with a lot of contrails are gloomy are because the atmosphere is able to support a lot of clouds and not because of the contents of the contrails.
Still I can absolutely see why people think chemtrails do exist and I can't deny they don't exist without seeing actual evidence!
-Alex

Contrails are not a new phenomenon. The reason they may have become more noticeable over the years is twofold. There are more planes flying around to more places than a generation ago, and contrails may have become more persistent due to a documented increase in atmospheric water vapor (most likely due to a warming atmosphere), resulting in a much more dynamic water cycle (with more flooding, record snows, and drought). In any event, why is this being discussed on the Palm & Cycad forum? I suggest you post your environmental concerns on the 'Hot Topics' or 'Nature' forum, and you will certainly generate more of a reaction, and potentially reach more people who are willing to listen to your message.

Tropicalzone7 Alex - have you watched the videos I posted with "Angel's Hair" fallout? Those are the evidence. I see and touch them every day and paid disinfo shills call them "spider webs". It's hard to test them though as they disappear once being touched. What keep most people from testing the chem strings soil and rain water is the high cost of sending them to the lab. Some people did test and found high levels of aluminium and barium in their soil, rainwater and their blood stream, which is yet another evidence. Those test results exist on the web. Yesterday was a huge chemtrail spray ever, and then an earthquake... some scientists write that chemtrails, HAARP and earthquakes are connected. Always look for those chemtrail falout hair in your yard in the afternoon, look towards the Sun and take your time to see them. Once you see them, you will not miss them. They fall on one's face, hands, irritate the nose, retard the plant growth. Chemtrails dim the sun letting less sunlight onto the soil and the plants, this is why they call this project SRM = Solar Radiation Management (a.k.a. Project Cloverleaf). Look those up. Protect your garden and your family. Don't go outdoors on the massive spray days. Wish you all well.

Here is a link that might be useful: Angel's Hair

Alex, there is a difference between contrails and chemtrails and you can often see them on the same day. 2 main things to look for are the checkerboard patterns, but the real proof exists all over the internet, and that is you can't turn contrails on and off, they are natural. There is ample pilot documentation on the internet of jets turning on and off their chemical laden poisons. Many meteorologists have made mention of chemtrails on the air, and most military are very familiar with them. There are a lot of people involved in the early days of climate manipulation that are experts in chemtrails, and if you look in the right places it's there. Try to prove it wrong, that's how most people discover the truth, that's what I did. But like I said earlier, it opens up a rabbit hole. Do you want to take the red pill or blue pill? I agree, there are other forums for this, but this is as perfectly relevant as global warming, which appears abundantly on many plant forums. I've always said man-made GW as presented is BS, man-made climate manipulation is not.

Well said