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Comment by AshleyGrant | Hacker News Reader

That was initially the plan. It proved too complex and has since been dropped from the design. It won't be coming back.

Which is too bad, because it would be really awesome if they had managed to make it work.

SpaceX's genius has never been getting the absolute maximum possible thrust out of engines. It's been designing them so they can be mass produced inexpensively, and re-used. They've proven that is the far more important skill.

So making the Falcon Heavy work as simply and well as possible is the important part. Getting another 10% by making crossfeed work, at the cost of making it more complex, harder to build and re-use, simply wouldn't be worth it.

Reproducible results is a skill set unto itself.

I think it would be worth it if they were not already looking working on BFR.

Falcon Heavy can fly for a couple of years now and it can handle current demands.

They will open up to next level capability with a next level vehicle.

I bet if Elon could turn back the clock he'd skip F9H and going straight to BFR. F9's Payload to LEO numbers have been going up; first design: 10,450 kg, current: 22,800 kg. On paper when Heavy was designed it was 25,000 kg to LEO.

I'm not sure. There are some things that the FH can do, military and space tourism and maybe a couple other things. Might be worth doing before the BFR, we will have to see how often i launches.

We just don't have the numbers, I would love to see the internal accounting of these projects.

I'd argue that if they put the engineering effort into BFR that much earlier, we might have a vehicle by now that can meet those demands as well as be a much better mars vehicle.

Are you quoting something that SpaceX said?

Do you have a source?

https://twitter.com/elonmusk/status/726561442636263425

That doesn't imply that cross-feed isn't coming back, only that it isn't needed for the capabilities Musk posted.

While that single statement might not imply that it's gone for good, everything Elon and SpaceX have publicly stated leads one to the conclusion that it isn't ever going to happen.

Heck, Falcon Heavy has turned out to be a much larger engineering problem than originally thought even without asparagus staging (cross-feed) due to issues with reinforcing the center core to handle the loads from the side cores.

Based on Musk's latest presentation regarding BFR, it seems that Falcon Heavy will be a somewhat short-lived launch platform.

Then again, with SpaceX, plans change early and often...

> It proved too complex and has since been dropped from the design. It won't be coming back.

SpaceX plans to do in-orbit refueling for its BFR, though. I may be oversimplifying, but it seems to me this is a fairly similar feat than cross-feeding. Couldn't the experience gained in this help for that?

Not really. In orbit, you can transfer your fuel slowly, gently, and the receiving tank doesn't have to be under pressure. During launch, you need the receiving tanks to be at 50-100 PSI for the rocket to work, which probably means the fuel being pumped at a pressure that is much higher.

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