4 ms·
They mean it needs to carry less oxidizer. The engines switch from air-breathing to on-board liquid oxygen at some point.
by wcoenen 9y ago
They mean it needs to carry less oxidizer. The engines switch from air-breathing to on-board liquid oxygen at some point.
- valuearb 9y agoThey have to switch to onboard LOX when intake air gets too hot to cool sufficiently. That occurs at Mach 5.5. You need to achieve Mach 30 to reach orbit, so all this fancy engineering can only going to be used for a small fraction of the journey to space.
- vilhelm_s 9y agoIt's a small fraction of the velocity, but a significant fraction of the mass. E.g. I think for the reusable missions, the Falcon 9 first stage cuts out around Mach 6, but the mass of the first stage (which is mostly liquid oxygen) is about 80% of the mass of the rocket.