The effective GHG potential is about 200x CO2. All of that, short of 6x direct effect, is secondary effects, e.g. scavenging the stuff that removes CH4 from tha

The effective GHG potential is about 200x CO2. All of that, short of 6x direct effect, is secondary effects, e.g. scavenging the stuff that removes CH4 from that atmosphere. It is not at all hard to look this up. But it doesn't matter very much for aviation; you make it on the spot, put it in, take off, and burn it all before it gets a chance to leak. LH2 does not seep through everything like gaseous H2. It's cold. It freezes stuff it touches, too.