Now for the opposite argument, which uses basic physics and math to demonstrate why Hydrogen is a EPIC FAILURE as aviation fuel.  It does it well, and definitely with the current aircraft used by the aviation industry, you can kiss off H as direct fuel for keeping the Billionaire Private Jets airborne.

However, this doesn't necessarily mean being grounded for good, if you're rich enough.  I see two possible solutions to the problem.

I mentioned one a while back, which is to switch from Jet engines to Rocket engines utilizing Solid Fuel propellant like the old Space Shuttle.  Ammonium Nitrate, also used for Fertilizer and making Bombs is used for solid rocket fuel.  This can be synthesized by taking Nitrogen and hydrogenating it over a catalyst to make Ammonia, then combining that with Nitrates created by oxidizing Nitrogen.  All these synthetic reactions require the input of gobs of energy, but this (in theory) could be sourced from renewable power generation.

The other is taking biologically sourced carbon compounds, such as Wood Gas or Ethanol, hydrogenating them and polymerizing up the carbon chain to 5-7 atoms and using pentane-hexane-heptane as your jet fuel.  This produces CO₂ when burned, but it's carbon neutral since the carbon comes from plants you grow to make the wood gas or alcohol.

This whole process would be very expensive and the fuel would cost a bundle, but this is irrelevant to Elon's $56B pay package.  Also explains why Elon & Jeff have Rocket companies, they need them to build their Private Rockets.

You however can kiss off your vacations in Hawaii, unless you have time to sail there.

https://cleantechnica.com/2024/07/01/another-day-another-hydrogen-transportation-firm-plummets-to-earth/

RE