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After a 24-second test of its engines, the New Glenn rocket is ready to fly

arstechnica.com

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Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#91

Post by quotemstr »

imtringued wrote: post #64
avmich wrote: post #12

Earlier quoted context omitted.

I hope Blue Origin succeeds too, but I'm not sure which mission profiles wouldn't be served best by the Starship in comparison to other launchers. There could be some ultra-light ones, where the cost for the whole launch is less than refueling the Starship, but...

Obviously any mission that goes beyond LEO that does not aeorbrake at the destination, because that means you're expending an upper stage with aerodynamic surfaces for no reason. Also anything that does a direct TLI or TMI, because you will have to stop for in-orbit refuelling.

Huh? If Starship can cheaply lift 150T to LEO, you can allocate some of that 150T to a propulsion system.

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#92

Post by Retric »

bryanlarsen wrote: post #81
Retric wrote: post #51

Earlier quoted context omitted.

2 billion at the high end isn’t actually unreasonable when compared to falcon 9’s costs which are sitting around 100m/launch right now largely due to inflation. There’s a have a fairly linear relationship between rocket payload and size, and for large structures going big tends to increase cost per pound so ~10x the size resulting in ~20x the cost is just mildly pessimistic. If and only if they the thing is both rapi…

> when compared to falcon 9’s costs which are sitting around 100m/launch right now largely due to inflation. SpaceX's financial situation argues very differently. They have raised relatively little money for a company that is spending multiple billions on two very expensive development programs (Starship and Starlink). If Falcon cost $100M per launch the 134 launches this year would have bankrupted the company. The $…

SpaceX has several million Starlink customers providing around 6.6 Billion dollars of revenue in 2024. It not clear if it’s profitable yet, but it’s been stated to kick off 100’s of millions in positive cash flow.

As to the salaries of its employees, that’s a major component of launch costs. You can’t point to it and say launch costs must be cheap because they are paying all these people when a large fraction of them are directly or indirectly working on launches.

They are spending ~2 billion per year on Spaceship, but what they charge per launch varies widely. 5 crewed falcon 9 flight cost the government ~260 million each, and the 2 ISS missions where 145 million each. https://payloadspace.com/predicting-spacexs-2024-revenue/

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#93

Post by HPsquared »

dotancohen wrote: post #69
amluto wrote: post #27

Earlier quoted context omitted.

I would imagine far less. The LHC captures many channels of sensors (for spatial resolution) and captures at very high frequency (because the time scales involved are fast and also because LHC is doing time-of-flight measurements). I doubt that a rocket has anywhere near as many sensors (have you seen pictures of the LHC’s instruments? They’re basically all sensor), and I also expect that the timescales involved in r…

Combustion in the chamber happens at roughly the speed of sound in the F/O mixture. I don't know what the speed of sound in gCH4 is, but it's probably within an order of magnitude of air - air at 250 bar. This is actually extremely important to model. Early F1 engines (Saturn V, not motorsport) were exploding and the engineers pretty much got lucky with the baffle design. Having a suite of sensors and then a computer…

Speed of sound also depends on the temperature (i.e. speed of the gas molecules) which is high and variable. These kinds of coupled interactions make combustion instability really hard to model in CFD hence the importance of full-scale testing.

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#94

Post by HPsquared »

dotancohen wrote: post #79
frodo8sam wrote: post #77

Earlier quoted context omitted.

Not pure luck though, they tried 15 different baffle configurations. Would of course be easier to filter configuration in simulations.

There was enormous engineering effort put in with close coordination of physicists, but those 14 prior baffle configurations could have just as easily been 140. For a relevant example, even just the oil formulation for Water Displacement on the exterior of the steel Atlas rockets took 40 iterations. Hence naming the product WD-40.

I wonder how many of the other baffle designs and water displacement formulations would still have been "good enough" - not optimal but usable?

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#95

Post by ceejayoz »

numpad0 wrote: post #87
ceejayoz wrote: post #32

Earlier quoted context omitted.

Computers and materials came a long way since the N1, as Starship’s successful tests can attest to.

But they're still losing roughly as many engines as Russians did in N1, so that sounds like a dubious claim. What about the latter? Are they really not tracing the footsteps of the X-33 program?

What? Flight five didn’t lose any engines. N1 kept blowing up.

X-33 never got to a test flight, let alone a successful one.

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#96

Post by ben-schaaf »

perihelions wrote: post #84
ben-schaaf wrote: post #55

Earlier quoted context omitted.

I don't see how that makes any sense. Starship is 100t dry; simply the fuel costs of a launch will necessarily be higher than disposable alternatives.

Fuel is cheap: it's $900,000 per Starship launch, according to Musk [0]. No disposable rocket comes within even a factor-of-10 of that. [0] https://techcrunch.com/2019/11/06/elon-musk-says-spacexs-sta...

I was perhaps exaggerating a little with the fuel cost comparison, but we've had rockets like Astra R3 and SS-520 fly for under $5M per launch. Rocket Lab's Electron is ~$7.5M. That's all within a factor of 10.

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#97

Post by black6 »

Novosell wrote: post #8

How much data do you guys reckon they gather during this 24-second window? Gigabytes? Terabytes? I imagine they have redundant sensors for every measurement, if possible. The LHC generates 1 PB/s, though it filters it down to roughly 200MB/s[0]. I wonder how this compares. 0: https://www.lhc-closer.es/taking_a_closer_look_at_lhc/0.lhc_...

It depends on the number of PIDs and the speed of the data acquisition system. When I worked on the RS-25 engine project the engine had hundreds of PIDs, the low speed DAS was 250 samples per second, and the high speed DAS was 250,000 sps. The high speed DAS generated so much data that it was only started a few seconds before engine start so the recorders wouldn't fill up before the end of the tests (which were typically 500 seconds).

EDIT: something to add is that not ever PID was tied into the high speed DAS–only a couple-few dozen important PIDs.

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#98

Post by baq »

ternnoburn wrote: post #4
teractiveodular wrote: post #2

We're at 12 years of design and 5 years behind the originally announced first launch of 2020 now. Space is hard, rocketry is harder and I wish them luck, but Blue Origin has an awfully long way to go if they want to catch up to SpaceX: this was meant to be the Falcon 9 killer, but odds are Starship will be fully operational before New Glenn completes testing.

Starship will serve a different mission profile. People seem convinced Starship will just "solve" space, but if it works, there's still going to be demand for other mission profiles that it won't make sense to send on Starship. But if your point wasn't to say that it will be obsoleted by Starship, and just to say instead it's slower development than Starship, yeah, that's true. I suspect the head start in infrastruct…

I’m not sure which profiles don’t make sense unless they can’t figure out payload doors. Stage 2 reuse means you can put up 50 tons or so of stage 3 in LEO for approximately free in current payload pricing terms, it’s a crazy number. (Advertised capacity of 100-150 tons is probably pointless and/or volume-limited anyway for a third stage.)

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#99

Post by basementcat »

quotemstr wrote: post #91
imtringued wrote: post #64

Earlier quoted context omitted.

Obviously any mission that goes beyond LEO that does not aeorbrake at the destination, because that means you're expending an upper stage with aerodynamic surfaces for no reason. Also anything that does a direct TLI or TMI, because you will have to stop for in-orbit refuelling.

Huh? If Starship can cheaply lift 150T to LEO, you can allocate some of that 150T to a propulsion system.

That means the customer has to buy an additional propulsion stage (plus time for integration testing and insurance in case it damages the launch vehicle, in case it becomes reusable). Also, it is not yet clear what the LEO payload capability of the vehicle is.

Re: After a 24-second test of its engines, the New Glenn rocket is ready to fly

#100

Post by aarmot »

ChuckMcM wrote: post #38
bryanlarsen wrote: post #36

Earlier quoted context omitted.

Even if it's not 100% reusable it's still likely to be cheaper than New Glenn. New Glenn uses extremely expensive methods of construction. Starship is assembled like a glorified water tank.

I'm not sure I see it that way, I wonder sometimes how much of the expensive construction can be systematized into something less expensive, and how much of Starship's "cheap" construction will remain as they work harder and harder to get to their reuse and turnaround goals. My intuition is that Starship will get more expensive to make over time and New Glenn less expensive but beyond that I can't say if they would m…

> ... Falcon 9 ... nearly 10 flights per booster

Just curious: what year is your data from?

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