>Eh, I'm going to give them the benefit of the doubt, mostly because they appear to be able to attract large amounts of VC funding. Just because someone is giv

>Eh, I'm going to give them the benefit of the doubt, mostly because they appear to be able to attract large amounts of VC funding. Just because someone is giving them money doesn't mean they can do it. >When it comes to orbital mechanics, the idea works. Of course it does, similar systems have been suggested for lunar transfers to earth (IIRC). Without atmosphere these systems are trivial to implement and use. (Comparatively) > Heat shields exist, and so do g-force hardened electronics. Heatshields are rather large and expensive. There is also a difference between heatshields for reentry and heatshields you'd need for leaving the atmosphere efficiently. At the moment, heatshields are basically ramming through the air and compressing it in front of the aircraft, this is most efficient in reducing velocity and can reduce the temperature at the shield somewhat. When you fire something through the atmosphere with the goal to get it into a suborbital trajectory you need a different solution; your aircraft becomes a spike/spear, generating friction with air instead of compression. Friction is harder to deal with if I recall correctly from various pages on the topic.