[carbonguy]

You're correct: methane would not work well as a replacement for conventional aviation fuel both for the reason you mention (weight of storage system) as well as the lower energy density per unit volume: 35 MJ/L for jet fuel vs. 9 MJ/L for compressed natural gas at 3600 PSI. (https://en.wikipedia.org/wiki/Energy_density)

[aaronblohowiak]

I think LNG would be more likely candidate , and doesn’t kg matter more than L here?

[sokoloff]

kg matters a lot, of course, but most airplanes are out of space for additional tankage as currently designed. (They are designed for a given mount of fuel capacity volume, in relation to the mass of that fuel volume. None would have a 4x multiple.)

Scaling volumetric storage by a factor of four produces about 2.5x the wetted frontal area (4 ^ (2/3))

[aaronblohowiak]

If I understand correctly LNG is 20MJ/L so not a 4x difference (but much colder, with all that implies...)

I would agree there’s a likely range reduction, but I don’t have any stats on current normal fueling as a percent of max capacity (iow: are there many routes that are running more than half full today?)