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What is Boeing going to be doing? No one has said.

Assuming there's no radical departure from the previous ILV design, Northrop was responsible for the transfer stage. I would assume Boeing will be building its replacement. Perhaps based around Centaur/DCSS/ICPS?

Centaur or DCSS sounds like a possibility, but why isn't it a ULA project then?  (I'll bet the word "co-manifesting" is somewhere in the explanation.)

I've always had a failure of imagination on the whole AE/DE/TE architecture.  I get that the AE is extensively crew-rated, and therefore well worth reusing.  The DE has to be expendable in the kind of form factors that ILV would be working with. 

The TE was advertised as being reusable, but every time I looked at what it would take to boost it back to NRHO and refuel it, it was just as cheap to send a new one, and a lot easier.

Maybe if you hack the RL10 off of the DCSS or Centaur, their attitude control systems have enough delta-v (60-80m/s) to get from BLT to NRHO?  That might make refueling and reusing the TE with the RL10 worthwhile.

Everybody would be sooooooo much better off if they'd just swallow their pride and buy methalox or LOX from SpaceX.  They can use some other heavy lifter(s) to send prop 10-15t at a time to a cislunar depot if Starship has some kind of problem.  But if it's working, it drops the cost of prop in NRHO by a factor of 10.

In addition to being expensive, the ILV was (and likely still is) tiny.  With more prop available, it might stop being a toy.
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Quote from: Eric Berger
Spoke with Chris Hansen, who oversees spacesuit and rover development for NASA. Asked about Axiom's timeline to deliver Artemis suits in mid- to late-2025, he replied, "I’m very confident that they’ll make these schedules that we’re talking about."

https://twitter.com/sciguyspace/status/1601275210858221574
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but it will never be safe enough for the general public, which is it's express reason to exist.

Never say never.

Starship is being built by the company which is regularly transporting people to orbit on the Crew Dragon. Nobody is afraid of flying that one. I think that bodes well for the future of Starship.

Dragon has abort modes and an inherently safe method of EDL (doesn't require a liquid propulsion system to work).  And it's still not safe enough for the general public.
Presence of absence of abort modes does not inherently confer or remove safety. All they do is reduce some specific risk that is not reducible any other way.

We do not care that solid motor abort towers are normally jettisoned just after the first stage burn completes leaving a capsule 'abortless' riding a fully fuelled second (or possibly third) stage. There are abort options using e.g. a capsule's service module on-board motors to escape a stage that gracefully fails (e.g. contained engine failure), but if the stage RUDs then you don't have a backup abort option. We accept that making the stage sufficiently reliable is an acceptable alternative. We do not demand adding abort-abort motors in the event of an abort motor failure, we just accept that abort motors can be made sufficient reliable.

We have demanded that trans-oceanic aircraft must have multiple engines, and have then happily compromised from requiring 4 engines with engine-out to accepting two engines of sufficient reliability without any engine out capability (ETOPS). We do not concern ourselves that aircraft have no abort-modes from wing failure (despite it being a failure mode that has occurred in flight) as long as we have deemed the structure sufficiently reliable and maintained.

No commercial car has an abort system in the event of a steering assembly failure, despite that being a single point of failure. We accept that the assembly can be made sufficiently reliable to not require one.


The common theme is that if a system or component can be deemed to be sufficiently reliable, we are happy to accept that there is no abort mode. In the early days of human spaceflight abort modes were a necessity because there was no avenue to system maturity within the timeframe required to start flying humans within. Starship is not under that deadline: it can wait to fly enough to demonstrate reliability before launching or landing humans, and the only deadline is whether Maezawa is willing to continue to push back the launch date (or willing to pay a little extra for EOR launch/land using Dragon).

I seriously doubt that SS will ever get to be reliable enough for the general public to justify having no abort system. Not without major changes.
In the sense of being in the same category as schedule passenger aviation, I agree. It'll take decades to get there. It'll be beyond 2050 even with the most optimistic assumptions to get to ~99.9999% reliability needed for that (100,000 consecutive successful flights WITH close call analysis and some level of PRA). I don't see Starship going 30 years with no major changes.

But there's a big gulf between where we are and that, where space (and hopefully deep space) becomes accessible to any of the sufficiently-motivated portion of the middle class (think similar to what the suborbital spaceflight folks were targeting, like XCOR and Virgin Galactic).

The fact that it runs on a huge amount of methane may prevent enough flights from happening. Peter Beck and I agree on this.  Watch at 1:22:54 and for the next 90 seconds or so.

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If there are two providers, it's not a monopoly. It's a market with a dominant provider. It's not gouging to charge just barely less than the second provider, it's market economics. A monopoly picks a price that maximizes net revenue. If the market is elastic, lower prices result in higher sales but lower profit per sale, and there is a point on this curve that maximizes total profit. The existence of a second provider puts a cap on the price the first provider can charge.

If SpaceX could sell prop in cislunar, then there would be:

1) Two HLS providers (LSS Option B and whoever wins SLD).
2) One cislunar methalox provider (SpaceX).
3) One primary platform (Starship tanker) for sending the methalox to cislunar, and a secondary platform (FH with a ~15t methalox tank and some RCS as a payload), in case the primary is unavailable.  Whether they'd actually build the FH tanks ahead of time or just guarantee they'd be available if there's a problem...  I don't know.

That's a SpaceX monopoly on cislunar prop.  But it still has full redundancy.

This is probably off-topic for a BO/NT thread, because getting Blue to be dependent, even briefly, on SpaceX prop would probably cause Jeff's head to explode.  There's also the issue that the Blue Moon lander runs on hydrolox, but even if they only took LOX from SpaceX and shipped their own LH2, they could make a much bigger system that would actually be semi-useful, instead of a toy.  And it would cost less.

BTW, I agree with you that there's still price elasticity in a monopoly market.  And if there's one company that benefits from increased BEO traffic, it's SpaceX.  So I'd guess that they start out being fairly generous on pricing.  After a while, when they've created a bunch of demand, if nobody steps up to compete, then things might get ugly.
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Here's a presentation on the Lunar Flashlight propellant system. They are using AF-M315E, which is a hydroxlammonium nitrate ([NH3OH][NO3] or HAN) monopropellant mixed with water. They get an impressive Isp of 231 s and a very high density of 1.467 kg/L!
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When/how was Leidos revealed as the sensor subcontractor to SpaceX on the Tracking Layer Tranche 0 satellites?

There was no mention in the initial news from October 2020.
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AIUI. Both the Collins or the Axiom EVA suits are based on the xEMU EVA suit. Which IMO means that they both will have a high unit price along with high operating cost and high sustainability cost. Hopefully there will be a less costly commercial EVA suit available in the future.
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CASC has posted a 5 minute long introductory video on the SD-3:
https://m.weibo.cn/detail/4844795904918568
Some stills from the video that show the rocket configuration.  The fourth stage appears to be a solid motor in an airframe that also supports a liquid reaction control system.

 - Ed Kyle
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Sorry to break the conversation.... but.... does anyone know what is happening with the development of the landing barge for New Glenn?
Jacklyn was scrapped in favor of SpaceX-like droneship due to high cost




Thank you, but yeah, that is known... what is not known is the progress on the replacement of the former Stena Freighter, Jacklyn with a landing barge/droneship..

https://twitter.com/SciGuySpace/status/1537099932926152704?s=20&t=ZDVQUpK3JQLNRneyYyHnRg

What is weird about this contract, is LAD Services, Amelia, Louisiana make no mention of New Glenn, and Blue Origin on their website...
https://ladcompanies.com/projects/


PS: I do not think that the  cost of Jacklyn was the problem, I think this issue was one of safety... having this large vehicle landing on a crewed ship, while still containing fuel that could be close to an explosive fuel/air mixture ...
The quoted source says otherwise
https://twitter.com/Michael10711597/status/1537294722485538817?t=iECtxgjQe9Sgc63svJ-BnA&s=19
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Commercial Space Flight General / Re: Skyrora
« Last post by Steven Pietrobon on Today at 02:56 am »
I'm no expert those figures don't look too shabby for a pressure fed HTP at sea level conditions.

Or is that just my ignorance talking?

That is not an ignorant conclusion. In comparison, the old pump fed British Gamma HTP/Kero engine used on Black Knight and Black Arrow had a sea level Isp of 2108 m/s (215 s) and vaccum Isp of 2450 m/s (250 s), so they are getting quite good performance considering the propellants being used.
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