Fusion propulsion

In fusion news, Pulsar is plotting the Sunbird engine. h/t Angry Astronaut interviewing Richard Dinan, at the convention in London.

AA's own titling needs work ("faster"? really?). The website, naturally, is better: Duel Direct Fusion Drive (DDFD)... specific impulse (10,000–15,000 s) and 2 MW of power. Dinan in the interview is talking about deuterium + ³helium, to limit neutrons. They are testing in vacuum chambers now; 2027 for space.

This is an interplanetary engine: With Sunbird in Orbit: A spacecraft launches to LEO (~9.4 km/s), docks with a Sunbird, and then the Sunbird’s fusion propulsion handles the rest. 3–5 km/s to Mars or 6–10 km/s to Jupiter. The initial launch vehicle only needs enough delta-V to reach orbit, not the full interplanetary trip. Meanwhile it can also supply the Moon.

A slight problem I got with the lowered propellant mass is that the propellant is... deuterium and He-3. He-3 is mad expensive compared with, say, chemicals or ionised argon. So I see this more as a means to get to outer planets where, in fact, He-3 might be cheaper.