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Old 26th February 2011 | 16:29
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Genghis the Engineer
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sfc data is readily available from Janes - I find the paper version much more user friendly than the electronic version, but you should have that in the library. The back part of each volume has the engine data.

Emissions are in reality really complex, but most simplistic analysis tends to work on a fixed figure of 3.15 tonnes CO2 per tonne of fuel burned.

In reality, there are other chemicals in fuel emissions, and for example there is a trade off within engine configuration of CO2 versus what are called the NOxy compounds (NO, NO2, NO3...) and scientists who study this stuff are still spending a lot of time trying to decide what combination is least hazardous to the ozone layer.

There is a Royal Aeronautical Society specialist group called Greener by Design, and if you search on their work, you'll find a lot of published work - in particular I'd look at their various conference papers. Or look at the air traffic manual I linked above in my second paragraph, and the references in that.

There will be a series of other trade-offs you want to consider if you do this properly. A long haul aircraft will "tanker" a lot of fuel, which puts the mean weight (and especially weight at take-off an initial climb) up, and thus increases fuel burn and so all emissions. Short-haul flying usually comes out, comparatively, less damaging per passenger mile. Also look at the relative drag profiles of a slower turboprop versus a faster turbofan. The other major factor, although not well understood yet by current science, is that mixing of greenhouse gasses across the tropopause is limited - so greenhouse gas emissions from a turboprop, which is likely to spend most of its time in the troposphere, is likely to be in most analysis less damaging than a similar quantity emitted from a turbofan that spends most of its life in the lower stratosphere.

Also, whilst I appreciate that Glasgow is a bit out of the way, you might want to try a tool called "Google" that works well for us in the South. 30 seconds with it found the reference above, and quite a few others. Google Scholar is even more useful for academic work since it finds you the journal papers that carry most ivory-tower-cred.

G
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