The case for gas first
Liquid hydrogen has to be stored at −253 °C. That brings cryogenic tanks, insulation, boil-off management and a long list of new failure modes to test and certify. Compressed gas avoids all of that in the phases where we need to learn fastest: the combustor, fuel system and controls.
What 2026 showed
In April 2026, an industry ground test at NASA's Stennis Space Center ran a business-jet turbofan at full take-off power on 100% gaseous hydrogen (Airframer).
Hydrogen combustion works at engine scale.
The open questions are now about emissions, durability, fuel systems and certification, which is exactly where our program focuses.
The trade-off
Compressed tanks are heavy and bulky, so gaseous hydrogen suits ground testing, demonstrators and shorter missions first. Liquid-hydrogen compatibility stays on our long-term roadmap.
What's next
Our first test phase targets safe hydrogen handling, controlled ignition and stable combustion, with an evidence pack at the end. Follow along on our Program page.