Garmaine Staff asked 2 years ago
Even if you don't care about hypergolicity, there's the serious problem that most storeable chemical fuels are either horrifically toxic (like N2O4), dangerously unstable (like high-test peroxide), or both (like hydrazine).
LOX does not have this problem, but as a cryogen it is difficult to store, and it also has handling hazards due to its tendency to turn flammable or combustible materials into contact explosives.
On the other hand, cold gas thrusters have abysmal Isp and arcjets require nuclear-tier power sources.
But then there's hydrocarbon (possibly propane or butane, since these are H-heavy and can be stored in pressure tanks at reasonable mass ratio for small quantities) with N2O.
While this doesn't look like a high performance fuel, it seems like it would be pretty good from the standpoint of safety. Is this indeed the case, and does it have any deal breaker like unmanageable combustion?
(I'm specifically interested in cases like RCS thrusters and orbital maneuvering thrusters where liquid-fuel levels of controllability are necessary.)