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Old June 5th 13, 11:33 AM posted to uk.transport.london
[email protected] spud-u-dont-like@potato.field is offline
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First recorded activity at LondonBanter: Feb 2013
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Default Bozza on Crossrail

On Tue, 4 Jun 2013 21:41:47 +0100
Roland Perry wrote:
In message , at 15:34:50 on Tue, 4 Jun
2013, d remarked:
Just for fun I did the calcs for your methane suggestion:

methane it atmosphere = roughly 1.8ppm

A commercial a jet engine takes in roughly 1 ton of air per second (going by
online figures) which for a high bypass turbofan means 100kg of air gets into
the compressor per second.

For a 10 hour flight that'll be 0.1 * 3600 * 10 = 3600 tons of air in
which there'll be 3660000 * .0000018 = 6.6 tons of methane.

Assuming all that methane gets burned (it won't but hey) thats equivalent
to about 165 tons of CO2.

A 747 uses 150,000 litres of kerosene on a 10 hour flight which will create
about 400 tons of CO2 which will be in the atmosphere on average for the next
10K years.

Therefor I think to sum up one can say nice idea, but no cigar.


You appear to have ignored the greater greenhouse effect of methane,
versus Co2.


Which bit of 6.6 tons of methane is equivalent to 165 tons of CO2 did you
not understand?

And of course this is ignoring the other pollutants jets give out such as
NOx and soot which also contribute to the greenhouse effect.

--
Spud