Is that 150t of payload or total? What’s the cost in fuel alone (let’s ignore maintenance and operations costs for now)? I’m trying to get a feel for the relative scale compared to today’s commercial flight.
They previously threw around a number of around $1M per flight, as mostly fuel costs.
Also, while 150t is the target payload capacity, the current test vehicles are closer to 50t in payload capacity, there are revisions in the pipeline based on data from these test flights which will bring it up to 150t.
To put this in perspective: at 150t/launch, if a launch is $1M, then for the cost of an SLS launch (at least $2B) Starship could launch 300,000 tons, about the mass of three Nimitz-class nuclear aircraft carriers.
None of the vehicles have demonstrated any payload capacity yet. 50 tons is the on-paper capacity only, and seems quite high given how little fuel is left when the bring an empty starship to orbital altitude. I assume that as the engines and launch procedures get more efficient, they will start being able to bring stuff to orbit (and quite a bit of stuff, too).
They've actually been having to dump propellant in order to more accurately test what a Starship in orbit would be like, given they're not flying with a payload that would consume that propellant on ascent, but that they still want to launch with a full tank.
The dumping of this excess propellant actually caused an explosion and loss of vehicle on the second test flight.
That's what they said about the second test flight (and the third), but the webcast recordings looked a lot more like fuel leaks to me, and that is in line with Starship and early Falcon's past issues. I'm going to press X to doubt that the dumping narrative is the truth, since a nice face-saving white lie is in every corporation's handbook.
That's a weak rebuttal. It's not disputed except by the lunatic fringe - starship has carried a payload (although not quite to orbit, very close to).
Whatever that means is what it means, the ship was out of control and I don't know whether or not the mission requiring that payload was successful, but the fact is that it did carry the payload.
Methane is about 900-1500$ / ton. About 1000 tons is used for the launch in addition to 3600 tons of lox. That should be a bit cheaper than methane per ton. Ballpark, the propellant might cost around 2M$.
A modern airliner on a long flight might burn around 80 tons of kerosene. It's slightly cheaper than methane. Call it 75-80K$.
Indeed. You sometime see an argument that launch to space is expensive because of the propellant and therefore energy required. And as you note this argument is utterly wrong.
Am I mistaken, or are there distance/payload combinations for which Starship is cheaper per pound on a point-to-point basis than air transport, even setting aside 30 minutes versus 12 hours? Isn't that the non-intuitive outcome of ballistic trajectories?
No. But it gets within an order of magnitude, which is remarkable. Economy class on starship could be priced similar to first class tickets on transoceanic flights.
There are no dollars in the laws of physics. It's connected ultimately to productivity of all the activities involved, and there's no obvious upper bound to productivity.
Just the current market price for fossil methane, which of course goes up and down. But I'm assuming SpaceX gets their methane on the open market.
It's quite possible that SpaceX has access to some cheaper methane source. Texas produces a lot of it.
And SpaceX has speculated about eventually switching to some renewable source by e.g. synthesizing methane. In which case that would boil down to cost of electricity and carbon. I don't see that becoming cheaper short term but that could happen long term.
Also, while 150t is the target payload capacity, the current test vehicles are closer to 50t in payload capacity, there are revisions in the pipeline based on data from these test flights which will bring it up to 150t.