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Comment by SCM-Enthusiast | Hacker News Reader

SpaceX's Raptors cost about $250k each according to some leaked sources. Given there are 33 engines in the booster, you get 8,250,000 just in engine costs. I would say it's safe to assume around 30% of the cost of flight is in engines, so probably around another 5,775,000 for the rest of the craft bring it in at around $14M for just the booster hard costs. That's not accounting for the $100m crane they've built, labor, propellant, nor the Starship itself which has another 9 engines.

Keep in mind that the RS-25's cost $100m each. If it was atlas, the engines alone would cost $3.6B.

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I was under the impression the $250 was a long term goal, not a current development cost. Do you know what context you heard this in?

Edit: propellant is relatively cheap I believe. My understanding is <$1m per launch.

initially the merlin engines were $2m each, with raptor v2 coming in at under $1m, and they are pushing out 1 Raptor v3 a week now, so i'm sure they've come close to their goals. You might want to push that number up by 50% to get a more realistic estimate, and then by another 100% to include labor, propellant, etc.

$44m per booster starts to sound like a more reasonable number.

The number of iterations Raptor has seen is kind of insane. V3 seems like it’s a substantially different beast compared to the original.

I suppose that’s par for the course when bringing a previously lab-bound type of engine into practical use, but still. Did Merlin see iteration at such a pace prior to being fitted on Falcon 9’s? Raptor looks to be on track to be in a considerably more refined state when Starship goes into service than Merlin was at during the same point with Falcons.

There's a video that i can't find, where they show Raptor v1, next to raptor v2. The raptor v1 has all these wires, and tubes and looks crazy, next to it, the raptor 2 looks super sleek and not that complex. They ended up molding everything they needed straight into the block itself. Can only imagine what the v3 designs were since they are now all internal.

But what you get at the end with something like 3000 parts in it's BOM, to something like 20 parts in the BOM, because most of the parts were deleted and integrated directly into the mold.

Perhaps this video? Everyday Astronaut: Elon Musk Explains SpaceX's Raptor Engine! https://youtu.be/E7MQb9Y4FAE?t=140

Merlin saw much less major iteration, but with that it's worth considering that there is a lot more experience with Kerolox engine design out there (plus a much simpler combustion cycle). Plus it was based on a NASA reference design. I do recall from Eric Berger's Liftoff book, they struggled with the nozzle design though. Very early Merlin had an ablative nozzle.

I suppose the better way to put it might be that Merlin's iteration was more in getting the production sorted out, whereas Raptor is iterating everything based on lessons from Merlin and previous Raptor iterations.

And this is why I am disillusioned by this whole ordeal. People just take rumors and treat them as certain facts.

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