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SpaceX set to re-fly a Block 5 rocket for the first time tonight

arstechnica.com

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Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#31

Post by growlist »

AgusBena wrote: post #26
lorenzhs wrote: post #23

Earlier quoted context omitted.

You're missing the point of Ariane. Its purpose is providing independent access to space for ESA member nations at a reasonable price, and as insurance against a launch monopoly (it upper-bounds what others can charge ESA). Ariane 5 is also extremely reliable, which is very important for some launches (NASA's James Webb telescope is going to launch on Ariane 5, for example). Ariane's goal is not to win the most comme…

One of the main goals of the Ariane rocket system is also provide jobs,not efficient Lunch system. If they create a reusable lunch system what the workforce will do then?

Given Ariane's French roots I think we can count on the lunch and all other meals being not just efficient, but superbe!

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#32

Post by mikeash »

growlist wrote: post #15
InTheArena wrote: post #13

Earlier quoted context omitted.

It was a epoch defining change. It does feel like a ton of time ago, and everyone in the industry (most notably ULA, Arianespace and the Chinese) are trying to figure out what they do now that the SpaceX steamroller is in full force.

Indeed. Could be that having a legacy rocket programme is if anything a hindrance in this new world of reusability - Ariane in particular seems to be in danger of becoming mainly an employment scheme that builds rockets on the side. For fairness I guess I should say SLS isn't looking too clever at this point either.

I don’t think SLS ever looked good, except when evaluating it for pork value.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#33

Post by mikeash »

lorenzhs wrote: post #24
bosdev wrote: post #4

Earlier quoted context omitted.

The first stage is significantly larger and therefore more expensive than the second. My guess is the first full-reuse rocket you'll see will be the SSTO BFR.

> SSTO BFR [citation needed] - I don't think BFR is intended to be single-stage to orbit?

The BFS (spaceship, i.e. second stage) is supposedly going to have enough performance to make orbit on its own as an SSTO, with a tiny payload. It probably won’t ever be used that way, though.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#34

Post by fooker »

mikeash wrote: post #33
lorenzhs wrote: post #24

Earlier quoted context omitted.

> SSTO BFR [citation needed] - I don't think BFR is intended to be single-stage to orbit?

The BFS (spaceship, i.e. second stage) is supposedly going to have enough performance to make orbit on its own as an SSTO, with a tiny payload. It probably won’t ever be used that way, though.

Human beings going for a 7 day trip around the moon is a tiny payload and some people would pay ..say.. ~ 300 million for a ticket, I would guess.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#35

Post by mikeash »

fooker wrote: post #34
mikeash wrote: post #33

Earlier quoted context omitted.

The BFS (spaceship, i.e. second stage) is supposedly going to have enough performance to make orbit on its own as an SSTO, with a tiny payload. It probably won’t ever be used that way, though.

Human beings going for a 7 day trip around the moon is a tiny payload and some people would pay ..say.. ~ 300 million for a ticket, I would guess.

You need supplies to keep those humans alive for a week, and a huge amount of fuel to boost the ship into a moon-intersecting orbit. Not a tiny payload by any means.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#36

Post by wahern »

thekingofh wrote: post #27
gliptic wrote: post #25

Earlier quoted context omitted.

The refurbishing costs of even their first reused booster was less than half the price of a new booster [1], so something above 50%*70% = 35% saving assuming that the booster is 70% of the cost of the launch. The new block 5 version rocket is supposed to reduce that refurbishing cost by a lot. However, they have development costs of something like a billion dollars to pay back, and no reason to lower the price drasti…

From that link. Holy cow: "“Looking forward for reusability, we don’t believe it really, really counts unless you can turn it around rapidly, or almost as rapidly, as you turn around an aircraft,”. I had no idea they were aiming for this level. That is just mind boggling how drastic a change it's going to be.

Musk's Mars plan depends on reducing the marginal costs of launching so much that SpaceX could with minimal expenditure chuck dozens of rockets at Mars every year loaded with supplies and crew.

This is important to keep in mind when wondering why a corporation would continue pushing its costs down after obtaining an effective monopoly. As long as Mars is the goal SpaceX won't turn into a ULA or Ariane. But if for some reason SpaceX ceases to pursue Mars then it would likely recapitulate the same business decisions of every other spacefaring corporation.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#37

Post by the8472 »

InTheArena wrote: post #10
mozumder wrote: post #3

OK I get that booster reuse cuts down costs, but the fact is the 2nd stage is still not reused, which limits the economic benefits needed to open new markets. We get a 50% reduction in costs, instead of the 95% reduction in costs. You can get a 50% reduction in costs just by going to India for launch.. Is SpaceX going for 2nd stage reuse at all? That's going to be a lot harder than booster stage reuse, since you're r…

The first stage represents about 75% of the cost of the vehicle, not 50%. This represents the actual cost of the metal on the launchpad, but not the services around the rocket, including launch control costs, etc. You can't take a rocket to India and you can't manufacturer that rocket in India (Skilset, US based corporation, ITAR) so you can't achieve your savings that way. Even Russia - which is using a very old tri…

> they are looking at that for FalconX

I have not heard of that one and neither has google.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#38

Post by fooker »

mikeash wrote: post #35
fooker wrote: post #34

Earlier quoted context omitted.

Human beings going for a 7 day trip around the moon is a tiny payload and some people would pay ..say.. ~ 300 million for a ticket, I would guess.

You need supplies to keep those humans alive for a week, and a huge amount of fuel to boost the ship into a moon-intersecting orbit. Not a tiny payload by any means.

What if it is refueled in orbit? The BFS presentations hinted at that ability.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#39

Post by stetrain »

fooker wrote: post #38
mikeash wrote: post #35

Earlier quoted context omitted.

You need supplies to keep those humans alive for a week, and a huge amount of fuel to boost the ship into a moon-intersecting orbit. Not a tiny payload by any means.

What if it is refueled in orbit? The BFS presentations hinted at that ability.

To get other BFSes up there with enough fuel to transfer a useful amount would require them to use the first stage booster instead of just being SSTO.

Really there's no point to doing an SSTO launch in practice since the BFR first stage will in theory be just as reusable (if not more so) than the BFS second stage. Using the first stage booster greatly improves payload to orbit and has relatively low marginal cost once you've built and tested the whole system.

Re: SpaceX set to re-fly a Block 5 rocket for the first time tonight

#40

Post by oh_sigh »

ashraymalhotra wrote: post #9

> It is worth recalling that SpaceX only flew a "used" booster for the first time in March 2017. It's amazing this happened just a little over a year ago.

Have actual cost saving numbers been published? I remember reading estimates back in 2016 or so of ~60% but I'd be interested in what the real numbers were
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