Monday, October 10, 2005

Funny link of the day

Upon browsing spacedaily, I ran onto this story about interorbital sending people to orbit in 2008 - they've even sold tickets!?

I don't think this is going to happen.

The biggest problems I see are making a high-thrust reliable rocket engine, a high-mass-ratio rocket to put anything in orbit, and making a reliable re-entry system too. Remember, one has to have attitude control and a retro-fire rocket, a heatshield, parachutes. Climate control, communication...

Interorbital's hardware so far? They do have rocket engines of 5000 pounds of thrust, which is nice. That makes about or 25 kN. If one assumes the capsule size of 1000 kg, rocket dry weight of 1000 kg as well, and mass ratio of 10, the total weight will be around 20 000 kg. To get even half a g of acceleration, they'd need 300 kN of thrust. If they double their engine power, they need only six of them. I don't know if they're pressure-fed (heavy tanks) or have turbopumps (expensive to develop and manufacture).

No way, orbital missions by 2008. Comment!