Aerion AS2 are anticipating a production run of 300 units for their supersonic business jet in their first decade. There will only be space in the market for one of these, the other will go bust. Without a Boeing/Airbus/Lockheed/General Dynamics/MD etc. prime lead on the project the numbers are eye-wateringly frightening from drawing board to full production and certification - billions, not millions. The only hope is multiple, advanced government defence force-backed sales both for head-of-state passenger and special-role variants which need to be in the bag many years ahead of development program conclusion. They will run out of cash otherwise way before reaching the end game. Probably the highest risk investment game in aviation, aside from the eVTOL sector that is! Needs a good few fruitcake billionaire backers to keep the cogs rolling. Or a government.