/sci/ - Science & Math

I'm still mad this thing folded.

>>11950275
>>11950342

COONTINUED

SpaceShipOne masses of 0.9 tons. With three people that’s 1.2 tons. Using the new tank, it has a mass of 1.7 tons. We don’t know how much the TPS masses, but assuming that the fuel tank has a second hull around it, we can add 0.5 tons to the vehicle. This is probably conservative, but it protects the tank and we want minimal refurbishment. Lastly, lets add another 0.1 tons (100 kilograms) as an allowable growth for the vehicle, alongside maybe extra payload. This gives us a vehicle mass of 2.3 tons.

It takes 2300 m/s is Delta V to reach suborbit. Assuming our vehicle can hold 2.73 tons of fuel and has an engine ISP of 300 seconds, we get a Delta V of 2302 m/s. Not bad.

What does this mean? It means that a Kerolox SpaceShipOne could go from the ground to suborbit without the need of a carrier plane, and then be refurbished without the need to replace a rubber motor. It would be much cheaper and likely last longer. It also wouldn’t require the development of “SpaceShipTwo”, which is a sucky goddamn vehicle.

How much would it cost? Well as our vehicle reuses SpaceShipOne’s cabin (And airframe and wings), it has a crew of three. One is a pilot, so you have two customers. Kerolox fuel costs around $3/kg if we asume Elon’s Falcon 9 fuel costs are right (600 tons for $200,000). At $3/kg, our vehicle’s fuel cost is $5200 per flight. Assuming that we do a WDR and Static fire between flights, our total fuel cost stays at $16,000.

This means that a mission onboard costs just $8,000 per passenger. However amortization and refurbishment costs are real and probably decently high. Money can be saved.

Summary: Kerolox SpaceShipOne would’ve saved development time and money per flight.

Pic related is XCOR’s Lynx vehicle, which is pretty much what I proposed.