Questions about Spaceships

[Fred Brackin]

Originally Posted by vierasmarius

I don't think it states it in quite that way, but I see your point. There are engines like the Fusion Rocket (Hydrogen), AM Thermal Rocket (AM Catalyzed Hydrogen), AM Plasma Rocket (AM Boosted Hydrogen) and AM Pion (Matter/Antimatter). Any of those could replace the Hydrogen with Water, without requiring any new equipment.

Well, not in the Real World you couldn't.

The minimum operating temp for water is 250 degrees or so K higher than the max temp for liquid hydrogen and the mass of water is 7x the mass of LHyd per unit of volume.

You'd need the insulated fuel lines and tanks of the LHyd engine and the high strength pumps of the water engine and a lot of other flexible gear. Given the mass/volume differences between LHyd and water tankage wouldn't work out very eficiently either.

Even if it's possible it'd never be as cheap or as weight efficient as a specilaized engine.