RCgothic

In one video clip the radiation shield on Orion is an underfloor bunker down by the heat shield. In a different article it suggests building a fort out of supplies. In either event though it mostly amounts to putting mass between the astronauts and the storm which is mostly acheived by turning the spacecraft for position of the heat shield and service module. It's not a showstopper to not have a bunker in the capsule and it's not serious to suggest that if it really came down to it such a feature couldn't be added to a spacecraft other than Orion given a few years' lead time, time we do still have. Similarly, it's not a serious defence of SLS to claim LOP-G (the only possible destination for SLS/Orion) hasn't been awarded to Falcon Heavy yet. True, the ground integrated PPE/HALO hasn't yet been confirmed and awarded to FH, but whatever happens it isn't going up on SLS. If not integrated on Falcon Heavy, then separately on Falcon Heavy, New Glenn and Vulcan. Gateway itself will be resupplied by Dragon XL on Falcon Heavy - and that contact has been awarded. SLS simply doesn't have the flight rate to support the lunar gateway and lander necessary for its own missions, even if doing so was economical which it isn't. The boosters can't be spared for anything that isn't Orion. Whereas without SLS EOR is perfectly viable. Orion can probably go to orbit on Falcon Heavy, even if the crew goes up in Falcon 9. And it *definitely* can go up on New Glenn. From LEO a simple rendezvous gets it on an upper stage that can do TLI. No big deal, no SLS required. I don't think Orion is required either. None of the issues for BLEO are more than a few modifications to existing designs away. Falcon Heavy is already flying. The only restriction is availability of payloads. If it had to fly nine times (and one F9 crew) in a year to conduct a lunar sortie, it could. ULA are as reliable as clockwork. I have zero doubt Vulcan will fly before SLS and be a success. Vulcan is absolutely capable of sending a 3-stage lander to TLI in bits. I'm also confident Blue Origin will deliver New Glenn within about the same timeframe. They may not stick the landing first time out, but that's not critical to mission success. They play their cards very close to their chest, but if Jeff Bezos says something will happen chances are it will. SLS/Orion was the only game in town back in 2011, and however limited it was you just had to stick with it. It's taken over a decade to even begin to approach a moon landing, and at Boeing's pace it would probably take a decade longer. What's made program acceleration possible isn't progress on SLS though. It's the new generation of capable boosters that can take the only thing SLS can actually do and make it work. And we really wouldn't miss SLS that much if it were gone. (Seriously NASA, your boosters and programs need better names. STS, SLS, LOP-G, HLS, GLS, poetry in motion they ain't.)

SLS is going to be obsolete anyway. There's a good chance Superheavy flies before SLS does. And Vulcan. And maybe New Glenn.

Funnily enough for an uneeded rocket, Falcon Heavy is about to get a bunch of payloads supporting Orion SLS delivering Gateway payloads and Lunar resupply via Dragon XL.

I'm out of likes, but yes. Co-manifesting 1 stage of a 3 stage lander is not co-manifesting a lander.

I think the point of confusion is that Dreamchaser is not a second stage. It's a spacecraft like Dragon. Falcon Upper Stage would still be expended.

If Orion and SLS proofed into non-existence *today*, but the goal of a landing in 2024 and budget remained, NASA could have an HLS style contest to modify a capsule for EOR based on rendezvous with a full upper stage and be no further behind than they already are with the lander contest. (Orion was designed to have all its load on the docking port. That's how Altair was originally supposed to send it to TLI.)

So it gets a more powerful upper stage. Now it can send Orion AND not a lander to TLI. Still no crew on the surface. SLS Orion cannot do the job it was designed for. If it weren't for Vulcan, New Glenn and Falcon Heavy, there would be no lunar landing in 2024 or 2025 or ever.

High Lunar Orbit is not by itself interesting for humans. It's a step away from LLO, which is a step away from a landing. Two steps away from interesting for humans. Anything done in HLO or equivalent is simply makework as that's the only place SLS Orion can go. If you're designing a rocket to conduct a lunar landing, you either make it capable enough to co-manifest a lander all in one launch, or you embrace rendezvous. SLS/Orion falls into this awkward middle way where it can't do an all up mission by itself and can't really serve as an earth departure stage for anything other than Orion either. It depends on rendezvous with smaller commercial partners (which weren't available at its inception, so it lucked out there), when it would have been more useful dedicated fully to large payload and earth departure for EOR than half to a mandatory capsule. Worse, if your ultimate ambition is to go to Mars (as SLS has always been mentioned in tandem with since its inception), then SLS has very little to contribute to construction of a mothership. Flight cadence is just too low.

I have't seen anything substantaited against Eric Berger, as far as I can tell it's semi-libelous sour grapes from SLS supporters. A popular science editor of a popscience website is not required to be friendly towards a bad system. We can all add appropriations and divide by usefulness accomplished, Eric's not the only one lamenting SLS's opportunity cost. NASA Spaceflight stream gave SLS such a kicking earlier.

Yeah, it doesn't matter how much of the money given to AJR is for R&D and retooling or whatever, and what proportion is actually spent on constructing RS25Es and RS25Fs, bottom line is number of units out the door divided by appropriations. 16 engines refurbished at $127m each. 6 engines at $193m each to recertify and restart production. 18 engines at $100m each. That's $134m each unless and until they buy more. ($150m each if you include the refurbished RS25 original purchase price, but given some of these may have gotten value from previous missions flown that may be unfair.)

I also like Jim Bridenstine and I can just about see how excluding R&D and fixed program costs $900m might be the marginal cost to build an extra SLS each year. RS25s for flight 10 (excluding earlier, higher cost engines) are $100m each. SRBs $50m each. ICPS $200m. Core stage (excluding engines) $200m. That's $900m. But the program as a whole costs $2B per year and will cost that amount whether or not an SLS gets built. If two get built, that would be $2.9B per year if the $900m marginal cost is accurate, but I'd be extremely surprised if we ever see 3 core stages in a year due to manufacturing capacity limitations. You also have to consider the R&D costs to date $15B so far. So a reasonable estimate to 2030 is ten flights (as the engines have been purchased) for $35 to $39B. The actual cost as opposed to the marginal cost is therefore likely to be $3.5B to $3.9B each. If SLS gets cancelled after 2025 and five flights then it will have cost in the region of $5B per flight. And ok, as the timeline goes on and more flights happen the cost does eventually converge (at 2 flights per year and infinite flights) at $1.45B each. But in the same timeline Superheavy, New Glenn, Vulcan, Falcon Heavy will all be flying at at maximum 1/4 as much cost and far more than 1/4 the payload, flying commercially the missions that SLS/Orion should have been flying inclusive if it had just been designed a little larger and more capable, and people will look at that and go: "Well this is how we should have been doing it from the start."

For publically funded missions I'd take total appropriations divided by number of missions (inc cancellations not transferred). Doesn't exclude any R&D costs, years with no flights, or unused hardware. Saturn V? $42Bn in 2019$ for 16 missions. $2.7B each. Crew rating Falcon 9 and dragon R&D? $3.4Bn over 9 missions. $378m each. Commercial Resupply Services? $1.6B for 12 flights. $133m each. This way there can be no argument over who got what.

Falcon Heavy is $95m reusable to $150m expendable. SLS, if it flies 10 times by 2030, will have cost $3.5B to $3.9B each. There is no way it will ever cost as little as $900m. All up appropriations for SaturnV was $2.7B each in similar dollars btw.

Here we go again: Lovely view!

I think they had two Abort TranOceanic sites for each flight. An article I shared a few pages back was a flight director talking about having to make the weather call for shuttle re-entry and how they had to be as sure as possible what the weather would be at the landing site in 2h time because once the call was made there was no going back!

NOTAMs support static fire today, 150m hop tomorrow, possibly.

9.5t empty, 1.3t props, up to 6t Cargo = 16.8t, exactly the same as Starlink.

Dragon 2 with full cargo weighs as much as a full Starlink launch, much more than CRS. We've never seen Starlink RTLS so I don't think Dragon2 missions can.

Hop NET Tuesday looks like. Once again, maybe static fire Monday. At least we got as far as preburner and RCS today!

Spin/preburner test, no full ignition.

I don't think the pad can endure a longer burn. They'll need to build something studier for testing superheavy!

Static fire may eventually happen today! I've been waiting all week!

Just learned today that because of this whole Space Force thing, Cape Canaveral Air Force Station is now Cape Canaveral Space Force Station. I have a negative reaction to this. CCAFS was historic. :-\

SN4 near miss: SN4 ambient pressure testing? Some updated NOTAMs: All quiet regarding SN5 and SN6 the last few days.