SpaceX Updates (Thread 8)

By DocM
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Grand Master

DocM

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Just a heads up

 

The Eastern Range will shut down for a few weeks starting soon after Falcon 9 Intelsat-35e goes up Sunday. Maintenance etc.

 

After the range comes back, the first up to bat appears to be the Atlas V TDRS launch on August 3rd. SpaceX resumes with CRS-12 on August 10th.

Grand Master

BetaguyGZT

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SpaceX looking at using Raptor engines for the Falcon Program

Article link | SpaceNews.com website

59557f5b7f344_Raptor_test_firing_2015-09-25.thumb.jpg.a2961c4ed918c3ee729e4af349ffd32f.jpg

 

Quote

“We’ve worked a lot on this particular vehicle. A lot of the active components, the valves, have been redesigned and requalified for much higher levels and much longer duration,” she said.

 

Despite describing the Block 5 as the final version of the Falcon 9, Shotwell hinted at the possibility of a future version of the rocket that could use the Raptor engines designed for transportation to Mars. Shotwell said Raptor, a liquid methane and oxygen engine for SpaceX’s interplanetary spaceship, has undergone “many dozens of tests” and is progressing well.

 

“The original idea for those engines were to serve as a propulsion system for the big Mars system, but we are looking at the utility of it on the Falcon program,” she said. (emphasis added)

:woot::woot::yes:

 

Oh ... my ... giddy ... Aunt ... okay, let's dig into some citations and data. Gotta see where the numbers sit.

 

Citations: https://en.wikipedia.org/wiki/Raptor_(rocket_engine_family) and https://en.wikipedia.org/wiki/Merlin_(rocket_engine_family)

 

In order to make Raptor actually worth using on a Falcon-class rocket, a couple of things need to happen to justify it.

 

1) As we've seen, the 1/3 size "test model" Raptor engine kicks out just about 1,000 kn of force ASL. Merlin-1D's currently will do just about 845 kn ASL; although we've seen SpaceX demonstrate that the 1D's can (and will) handle 950 kn ASL without issues (citation: Inmarsat 5-F4's launch).

 

Any Raptor engines being retrofitted into a Falcon-M (my own working name for this derivative) will need to be an evolutionary increase better than the above. 25%~50% better would make a strong case for a refit. 1,250 kn of thrust ASL, but in a small enough footprint that it could be packed into the Octoweb neatly and integrated without a lot of hassle. We're also looking for as much of a "drop-in" replacement as possible, with as little redesign as possible (saving the company money and time). The plumbing connections, of course, that all can be dealt with quickly. Tankage, however, is another issue and will be dealt with by others.

 

I should note that a 25%~50% improvement in performance at this scale is already something that SpaceX has checked off on their list. :yes: Mrs. Shotwell wouldn't have suggested using these engines on Falcon if they hadn't already gotten to that milestone.

 

2) SpaceX would have the need to build it. This means retrofitting an already-mature platform. Would the Falcon-series rockets actually need upgrading? This becomes a question of want versus need.

 

3) Does this then become a case where it would simply be better to build a new medium-class rocket altogether? Possibly. Keep the Falcon-class for light-ish payloads, build the new medium-class for those payloads where it's not appropriate for ITS Junior? This would be the argument that would likely kill off any chances of refitting the Falcon line, in my view.

 

So what could we expect a Falcon-M's performance to be like?

 

We'll have to wait and see if they build it. ;) 

Edited by Unobscured Vision
Grand Master

DocM

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They're still looking at it, but to get to the point of saying it in public likely means it's further along than anyone thought :woot:

 

I think they'll use the 1,000+ kn Raptor engine on the upper stage, since that's what the USAF paid them to develop. Very likely an long duration ACES-like upper stage but with solar power rather than the 6-cyl reciprocating engine generator ULA opted for.

Grand Master

BetaguyGZT

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22 minutes ago, DocM said:

They're still looking at it, but to get to the point of saying it in public likely means it's further along than anyone thought :woot:

 

I think they'll use the 1,000+ kn Raptor engine on the upper stage, since that's what the USAF paid them to develop. Very likely an long duration ACES-like upper stage but with solar power rather than the 6-cyl reciprocating engine generator ULA opted for.

A FAR better option, imho. That 6-cyl generator has fail written all over it. Using something like that for space ... feh. I'd rather they use fuel cells than that heaping pile of bad ideas.

 

Solar is a proven technology, and good out to Jupiter. The panels they use on Dragon would do the job, and do it well. All they need is something to top off the TCU B+ for the Methalox, and the various systems on the S2.

Grand Master

DocM

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I think they'll use the circumferential solar arrays and thermal radiators from Crew Dragon/Dragon 2 for power, and radiating heat from a small cryocooler (to keep things chilled.) 

 

This way it could double as a Crew Dragon cis-lunar departure/return stage, leaving space in the trunk for other consumables to be passed through the Dragon Claw.

Grand Master

BetaguyGZT

Posted
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3 hours ago, DocM said:

Cool!!

 

What's even cooler is knowing twice as many have landed, and two have done it twice :woot:

 

The industry wonks, and trolls, who said this was impossible are extremely quiet lately. 

Yep, and plenty more to come. :yes:

 

Those industry naysayers are finding themselves locked out of the industry now, pretty much. OR they're being relegated to tasks that pretty much cut them out of the loop. Think of weather stations in the Arctic Circle ... things like that. Places and jobs that they wish they'd never pigeon-holed themselves into. Retirement is really the only option for them at that point.

 

SpaceNews.com seems to be the last bastion of the "old thinking" ... lots of anti-SpaceX people gather there.

Grand Master

FloatingFatMan

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Posted
On 7/2/2017 at 5:48 AM, DocM said:

Cool!!

 

What's even cooler is knowing twice as many have landed, and two have done it twice :woot:

 

The industry wonks, and trolls, who said this was impossible are extremely quiet lately. 

Sark0zy's head probably exploded in rage. :p

 

  • BetaguyGZT, SALSN and DocM
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Grand Master

DocM

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Here's a thought,

 

Elon Musk ✔ @elonmusk
Thanks PayPal for allowing me to buy back http://X.com! No plans right now, but it has great sentimental value to me. 

 

Jonathan Wilkinson @jondaily83
Replying to @elonmusk
I've got a cool idea you can use http://X.com as an umbrella website to all your other companies. 

 

Elon Musk ✔ @elonmusk
That's probably the best use

 

Single letter domains go for $megabuck$, Z.com went for $6.8m, so it meant enough to drop 7 figures on.

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