# Chemitrails/Contrail and factors

1. Jan 26, 2013

### Numeriprimi

Do you know chemtrails? http://en.wikipedia.org/wiki/Chemtrail_conspiracy_theory

I want scientifically prove it is condensing lines to my friends.
I know this is just condensation lines for aircraft. However, how do I prove them? Is there any information that is inconsistent with the fact that it chemtrails really are?

The aircraft must be 8-12 km above the ground for the formation of condensation lines. However, sometimes condensation lines don't incur... Dependence on atmosphere, humidity, speed ... And what do you know you about it? What factors depends on the shape and length of the condensing lines? And how?

And now a little physics ... How can we calculate the length of the condensate lines?

(sorry for my English, if you don't understand me, write, I will try to write it better)

2. Jan 26, 2013

### A.T.

http://science-edu.larc.nasa.gov/contrail-edu/faq.html [Broken]

Last edited by a moderator: May 6, 2017
3. Jan 26, 2013

### bigfooted

These trails are basically water vapor that gets condensed. Some simple estimates...

Kerosene is basically n-decane. When it gets burned you get:

$C_{10}H_{22} + 15\frac{1}{2}O_2 \rightarrow 11H_2O + 10CO_2$

A 747 consumes about 10 kg of fuel per km.
You see from the combustion reaction that for each mole of fuel, it produces 11 moles of water (and 10 moles of CO2).
So 10 kg of fuel produces almost 14 kg of water. This water is in the gas phase at first, so it occupies a lot of volume.

A cirrus cloud contains about 0.03 grams of liquid water per cubic meter of air.
So if all the water produced during a 1 km flight would produce the same liquid water density as a cumulus cloud, the water vapor would occupy about 14000/0.03=460,700 cubic meters of air. Spread out over a cylinder of 1 km, the diameter of the cylinder would be 25 meters.