>>1935818The companies and the Air Force just learned as they went how to keep everything sealed up. Hydrogen isn't as explosive as the Hindenberg makes people think. It'll be stored as a liquid so that limits the mixing with air, and if it leaks on the ground, hydrogen warms up and rises quickly unlike jet fuel that stays on the ground and burns.
There isn't a whole lot published about hydrogen jet engines. The easiest one to read is a NASA history of liquid hydrogen,
https://history.nasa.gov/SP-4404/contents.htmThere was an early flight test called Project Bee, and then a Lockheed development program for the CIA called Suntan that used the engine I mentioned (see section 8-1). They gave up on the project when they realized the poor range (solving that eventually led to the A-12 / SR-71 aircraft)
