Re: Air-fueled aircraft on Titan

On Oct 22, 1:57 pm, thro...@xxxxxxxxx (Wayne Throop) wrote:
: jdnic...@xxxxxxxxx (James Nicoll)
: Titan has 50% more air pressure than Earth and much lower
: gravity, which would seem to make flight (both LTA and HTA) an
: attractive option for exploring that world. About 1.6% of the
: atmosphere is methane or something derived from it. Assuming the
: craft carries its own oxidizer [1], is it possible to directly
: use the methane in the air as fuel?

Eh.  Maybe better to ask it the other way around.
That is, what would prevent it?

If something does, it'd have to be something subtle,
since there's nothing obvious preventing it.  Unless there's
a trick question lurking in what "direct" means in this context.

I'm hardly an expert, but I see nothing subtle about it.

The problem is that the atmosphere is 98.4% Nitrogen, with only
1.6% methane. This is thin gruel indeed. You might want to
look at
http://www.eng-tips.com/viewthread.cfm?qid=154756&page=1
where one of the commenters says that the LFL (Lean Flammability
Limit) of Methane/air mixtures is 5% at 100 atm, and 2% at 700 atm.
I *think* this is relevent figure.

This suggests that a Titan/Oxygen mixture won't be flammable unless
it is greatly compressed - perhaps to 1000 atm or more. This is
difficult to manage in current engines. Modern jet engines get about
40 atm.

Peter Trei





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Relevant Pages

  • Re: Air-fueled aircraft on Titan
    ... Titan has 50% more air pressure than Earth and much lower ... which would seem to make flight (both LTA and HTA) an ... atmosphere is methane or something derived from it. ...
    (rec.arts.sf.science)
  • Air-fueled aircraft on Titan
    ... Titan has 50% more air pressure than Earth and much lower ... attractive option for exploring that world. ... atmosphere is methane or something derived from it. ...
    (rec.arts.sf.science)
  • Re: Hourly pressure readings in East London
    ... I think you are reading a bit low there Scott,.George at Epping and I are ... reading 968 atm ...... ... Air pressure seemed to steadily fall from about 9pm last night (Sunday ...
    (uk.sci.weather)