HLS Starship for Artemis Crew Missions

Congress and NASA have long stressed the importance of redundancy, especially with the recent sole selection of HLS spawning multiple hearings and a congressional mandate for NASA to have 2 landers. Yet Artemis has no for redundancy for crew delivery to the moon's orbit. This video series will investigate this dissonance and propose currently feasible methods for SLS redundancy.
Thank you to SPACESHIPMANIA for sponsoring this video. Please support his amazing KZbin Channel at / @spaceshipmania5476 and find free 3D models at www.thingiverse.com/spaceship... and finished models soon available at www.etsy.com/shop/SPACESHIPMANIA
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Thumbnail Render: ERCX
Chapters:
0:00 Intro
3:45 What is Needed for Redundancy?
6:33 HLS Ferry
14:46 HLS Tow Truck
18:22 Summary
21:06 Final Thoughts

[@mirien7277]

"Do you expect to just find a crew rated lunar vehicle in a junk drawer somewhere"

[@rexmann1984]

Wright Patterson AFB has one...

[@metalhead4700]

They should check lying by the side of the road... 🤔

[@simonoconnor7759]

Yes, it's right next to the Exploration Upper Stage SLS needs.

[@Oculaz]

Seriously, the work that goes into these videos is astonishing. Please please please keep going. You have so much potential with this channel!

[@Apogeespace]

Thank you so much! It's a lot of work but it is all worth it. Wish I could post faster. More is to come!

[@fish2468]

@@Apogeespace exited! Glad to know it

[@heaposan]

@@Apogeespace Persistence dude. You produce some of the best content in space KZbin.

[@NotOurRemedy]

Seriously he is the best. This stuff really is up there with EDA.

[@shrin210]

@@Apogeespace Thanks, if possible do 1 video per month. Your videos are such that i Can watch it again and again.

[@joshuafitch312]

I’m a Masters student in aerospace engineering and I’m a SpaceX intern and these videos teach me all sorts of new ideas and concepts! So well done. Two comments on these concepts: 1) the ability to do free return abort trajectories is more dependent on trajectory design and timing of burns, so it *may* be possible to design a Starship TLI that allows for some time period of free return options. LEO capture is a different story. 2) for the second concept, adapting dragons heat shield to accommodate re-entry from cislunar space is not trivial and may not even be possible due to geometry, flight path angle, ablative material design, etc.

[@tomekstanek]

But Dragon still will have abort engines, he will be able to use it before reentry , right?

[@joshuafitch312]

@@tomekstanek yes, and in theory they could slow down re-entry but it would still likely be much larger velocities and Mach numbers at entry. Not saying it’s impossible, but would require some real complex engineering to make it human rated by NASA standards again.

[@NetRolller3D]

I wonder if Orion/Vulcan is possible. Orion/Delta IV was demonstrated, but with Delta IV no longer in service, Orion/Vulcan is the closest setup available. Of course, this would only provide redundancy for SLS, keeping Orion as a SPoF.

[@steveaustin2686]

@@NetRolller3D The Delta-IV Heavy can not lift the Orion, ESM, and ICPS all in one flight. The Falcon Heavy when fully expended can do that, but former NASA Admin Bridenstine said that aerodynamics were an issue. He also said that NASA would look at the aerodynamics, but apparently nothing came of that. In any case, that only works for the first 3 flights as the SLS Block 1B uses the much larger EUS for Artemis IV onward. No way a Falcon Heavy or Delta-IV could fit an 8.4m diameter upper stage. BTW, the Delta-IV Heavy has 3 more boosters left, with one flying each year for NROL payloads. NROL-91 is currently scheduled for Sep 2022.

[@NetRolller3D]

@@steveaustin2686 Why would you want to lift the ICPS or EUS in the same launch? The idea is using Orion only to access the HLS Starship in Earth orbit in the event of SLS being unavailable.

[@richardmalcolm1457]

Re: HLS Tow Truck mods to Dragon: When "Grey Dragon" was last being bandied about, Elon also noted that Dragon would also need a major upgrade to its comms. Not a showstopper, to be sure; but something to note and add in to the development costs.

[@topsecret1837]

That’s a critical element for Polaris to solve.

[@eccentricity23]

"It's impossible to design any architecture that can withstand total failures at every single point" No kidding lol

[@chloekaftan]

that doesnt stop space-x from putting redundancies on their redundancies, lmao

[@saheem5647]

Brilliant video Kirtland. Love the in-depth breakdown. Only thing I was skeptical throughout the video was the $30 million price tag on starship. For early flights I was thinking more $150-$200 million but is still much cheaper and is within the allowable rate and I am sure that just like SLS, the more flights the less amount of $. Keep up the great work!

[@Apogeespace]

Yes, I agree the $150M-$200M price could be realistic (especially if we are talking about price charged to NASA for the flight). I should've have mentioned clearly that the $30M is an estimate for internal marginal cost to SpaceX for early reusable Starship launches. That number is based on the $28M number for internal TOTAL cost of falcon 9 flight. Even an early Starship should be cheaper than that number, due to eliminating all of the most expensive parts of a Falcon 9 flight.

[@steveaustin2686]

@@Apogeespace Internal costs to SpaceX are not as useful as the customer price. Yes, a Falcon 9 B5 launch internal cost is somewhere around $25M, but the customer still starts at $50M for a recovered booster.

[@devindykstra]

I love how much thought you clearly put into these proposals. No other channel I've seen discus these topics has ever mentioned the abort capability of SLS-Orion or the maximum thrust that the crew dragon docking port can handle. Absolutely amazing!

[@ironspider9280]

10:10 you meant to say "a full 2.1 billion dollars less than SLS"

[@gavinkemp7920]

Great video, I hope your subscriber count explodes because honestly you videos are on par or atleast almost on par with everyday astronautes and vastly superior to a lot of other space commentators. The tide bit I'd point out is that it doesn't make sense to have the tanker, the orbital tank and ferry at the same price point since the ferry would only be used for the lunar mission so the cost of the vehicle would have to take a significantly higher proportion of the cost. still we in different orders of magnitude so it wouldn't change your conclusion.

[@freddo411]

These videos are great. Keep it up. Don't let the YT algo get in your head.

[@cube2fox]

It is really beyond me why such a great video only gets a few thousand views while other space KZbinrs get hundreds of thousands with much more mundane content... Maybe because Starship wasn't in the title?

[@abireeves]

Your channel is one of my faves, your vids are amazing!

[@chillwill8438]

Ever since I discovered your channel about a month ago you have by far been the best KZbinr I have seen explaining the SLS missions and Starship Lunar Lander (or HLS). Your videos are so organized and the animations are so beautiful, and if I ever know someone that wants to learn more about the Artemis missions I will recommend your channel! So amazing :)

[@carsongbaker]

You are incredible. Graphics, content, and story telling are incredible.

[@fish2468]

third time coming back to revisit this video, love the professionally made content, the thoughts and effort is outstanding

[@Izayuukan]

It's taken KZbin 4 days to inform me of this video's release, but better late than never. I love this sort of content.

[@tomalekrx]

Great video once again! The tow truck method blew my mind! What a great idea. So smart

[@coreytaylor5386]

extremely well presented video, fantastic job!

[@isaacjohnson3503]

Can't wait to see you with like 1 mil subscribers and get to say I've been here since 18k!

[@Apogeespace]

You and me both!

[@cube2fox]

My guess is that redundancy for SLS wasn't planned originally because nobody expected there to be any cheap feasible redundancy options available. Now with Starship there are such options on the horizon. But because the old Artemis plans do not contain anything about redundancy for SLS, NASA has no motivation to include redundancy for SLS. It wasn't seen as necessary before, so why should it now? From their perspective, it would only make Artemis even more expensive than it already is. Of course redundancy for SLS would have the big advantage of providing, well, redundancy. But that's not a checkpoint in the original Artemis plan, so they ignore it. Moreover, redundancy for SLS has the potential to be reversed: Make something like the HLS Ferry the default moon transfer method, and let SLS+Orion play the backup role. This would massively reduce cost, since fewer expensive SLS launches would be required. It could be the beginning of the end of SLS. But I think NASA has already so much money poured into SLS (and planned to do so in the next years for its various extensions) that they are victims of the sunk cost fallacy. Oh well.

[@kenhelmers2603]

Cool models! I like this series. Exploring methods and ideas is fun!

[@rocketman1969]

These videos are always great!

[@Apogeespace]

Glad you like them!

[@rdmsh]

Apollo was amazing but it was too easy to be stopped by gov. I worry SLS is the same. Reuse, flexibility and high cadence is the key to keep it going

[@christopherbeddoe406]

Unfortunately, or maybe fortunately. SLS will be an absolute failure. There is no way they are going to stomach over $4 billion a launch when spacex can do it with greater capacity and capabilities for 10x less. NASA was so desperate to avoid using SLS due to costs they were investigating alternatives such as human rating Falcon Heavy.

[@Luigi-vr2pc]

Another amazing video. Hope you keep it up!

[@jeffvader811]

Lueders said the long term goal for SLS, after moving to commercial ops, was $1-1.5B per launch including ground systems costs. The RFI for that mentioned a desire for at least 50% cost savings (for hardware, ground systems and payload integration) for up to 2 flights a year. I personally doubt those cost savings are realistic, particuarly when they happen concurrently with substantial upgrades to both the vehicle and ground systems, but to be gracious I'd put its long term marginal cost at $1.1B instead of $1.5B.

[@Hokie2k11]

Great video, you need more exposure man. Love your work.

[@huskyhuskyhusky]

Amazing content! You are the best Space youtube channel out there. Keep it up man!

[@Apogeespace]

Appreciate that. I'll keep them coming!

[@aaronak2005]

Great video, I'm looking forward to more!

[@mossyslopes]

Very impressive work. Subscribed. 👍

[@graystoke8229]

It's called Senate Launch System for a reason.

[@JeremyIson]

Thanks for these videos.

[@basbekjenl]

I can't wait for a shipyard in leo, a place to refit and modify spaceships for missions, just send up a lunar shell and fit it out in space for the mission. The benefit being you can send it up light and get the cargo up separately. I just can't wait for a leo dockyard

[@aaronmcculloch8326]

The real first value in an orbital shipyard is going to be satellites, just ship up components by the crate, assemble them by a small crew and basically toss em out a window and let them putter to their target orbit, it would make satellites like 1% the cost is you didn't need to worry about the ways it can fail between the facility and orbit. Keep big tanks of the common propellants' on hand and a few sizes of generic busses and solar panels, and companies might even be able to order online and have their custom built satellite in orbit the next day, wiping out the whole concept of small sat launchers

[@steveaustin2686]

Eh, an orbital shipyard would likely be for assembling modular components into a larger spacecraft. Why do fiddly interior work in zero-g when you can do it on the ground and send up the complete module instead?

[@nottrevorallen]

you are a madman, thank you for these videos so much

[@mortallychallenged]

Thanks for another great video! It's amazing seeing the production quality improve since the begging. I think it will be more difficult to convert dragon to being capable of lunar reentry, the issue is dragon is designed to minimize total heating, because prolonged reentry causes the glue holding the heat shield on to melt. The heat shield mounting system would have to be redesigned. Something SpaceX could entirely do, but adds additional challenge

[@mtopley]

Crew dragon used for launch and landing is a great idea

[@stevepirie8130]

Looking forward to part 2

[@Dromfel]

Great video as always! Starship has just so much potential, it's sad so few people really get that. It's not just a new shiny rocket. If they can truly make it work (rapid full reuse), it's a revolution. price or capability of mass to orbit/moon/mars won't be the same anymore.

[@marcinzarebski7471]

Great video

[@MrGeyt2006]

really love your content, wish you posted more often but I understand there's a trade off between quantity and quality so just keep pushing them out at whatever pace works for you.

[@evrydayamerican]

I like the Tow truck version you did . To me it makes the most sense cool video

[@dr4d1s]

Thank you for the new video! The podcast helped tide me over but I was starting to get the shakes and the sweets. I will update my comment after I finish watching. I just wanted to engage the algorithm first so it would help get the video out to more people.

[@Apogeespace]

Thanks so much for watching and engaging!

[@dr4d1s]

@@Apogeespace No problem Ken. I just want to do my part to help.

[@nathanwestwick815]

great vid

[@yulpiy]

Very good

[@yulpiy]

Haven't even watched but it's my gut feeling

[@bastion9514]

Insightful discussion that needs more of us engaged in furthering this exceptional argument for HLS. My food for thought to this wonderful line of thinking is why not have Dragon on Starship HLS therefore we also have a safety abort system when landing on Moon. I see this as a cool way to provide additional safety margin at least in early development of Starship HLS system. therefore astronauts are being ferried mostly within Dragon during higher risk maneuvers. Excellent mate

[@alvianchoiriapriliansyah9882]

NASA selected Starship as HLS, and it doesn't have Dragons & its aborts. It's considered acceptable

[@iamarokotmanson]

For future videos could you do the delta v numbers and costs such as for the improving Artemis video?

[@rafaelschipiura9865]

It's not possible to add any weight to Dragon's trunk since that violates the flight envelope for atmospheric abort scenarios. It would require developing a totally new vehicle. And SpaceX doesn't use explosive bolts. They have shown that hydraulics, with the proper care, have better reliability.

[@evannibbe9375]

You could instead make several Crew Dragon trips to Starship with all of the extra supplies needed.

[@fellowabhi]

Oh man, I wish Nasa was seeing this

[@BBbrewer13]

Awesome video and detailed concept evaluation. One thought I have had about the HLS in general that I wonder what you think. I know in at least one official HLS rendering 3 Vac and 3 SL Raptors are visible. However, an HLS starship will never fire its Raptors in the atmosphere and will be confined to the vacuum of space. Why bother with the SL raptors? Maybe just omit them, save the weight and all burns in space done with the 3 Vac Raptors. Or replace the 3 SL with one c/l Vac Raptor gimbaling engine for Insertion burn control. Or just go with 3 gimbaling Vac Raptors maybe re-spaced away from the outer wall for proper spacing?

[@stonefreak5763]

The problem that I see is not, that NASA wants to use SLS, but the Government says they have to use it so the public doesn't think the money was wasted (even tho they would "waste" even more money this way) I mean, Starship is designed to land on Mars on its own and is selected as HLS, so it clearly is able to land on Moon on its own (even tho without any real abort systems), and we all know that it will be WAY cheaper to do so.

[@steveaustin2686]

Except that Lunar Starship will be out of propellant when it gets back to lunar orbit after the surface mission. Somehow I don't see NASA leaving astronauts stranded in lunar orbit waiting for a Tanker. Also, the missions that Apogee are talking about are when Starship matures a bit to have a faster launch cadence. The GAO report denying the HLS complaints lists a launch cadence for Artemis III of one Starship launch every 12 days. If Musk's up to 8 Tanker flights is needed to refill the [DELETE] propellant depot, then it will take a Starship Ferry to take too long to get to the Moon to make the Lunar Starship's lunar orbit loiter capability of 100 days.

[@ProgrammerDan55]

Great start to a new series. I look forward to the non-starship options, although these were a great place to start (since funded already!).

[@Apogeespace]

Yes! Can't wait to explore the rest of the awesome US commercial space industry!

[@richardsuckerson49]

Great video, I love the new architecture ideas; this should be shared around DC so that they can be reminded of how much potential SpaceX vehicles have

[@Waglou27]

Great video ! Saying that the starship tanker will be as simple as current starship prototypes seems to be a bit of a strech to me (cooling system + fuel transfer systems) + you forgot to mention that for the tow truck version dragon healtshield would need to be upgraded to sustain lunar velocities re-entry which might end up costing a bit

[@Apogeespace]

Sorry I don’t mean general tankers there I only mean expendable ones (ignoring the fuel transfer system which shouldn’t have a high material / manufacturing cost. Really only development should cost a lot in that domain.) I mention the upgraded heatshield in the dragon upgrade section. Thanks so much for watching!

[@rexmann1984]

@@Apogeespace when did this video hit? I just got the notification. Did you post it yesterday?

[@spacenoodles5570]

@@rexmann1984 under video title, 58 min ago

[@lazarus2691]

SpaceX claim that Dragon's heatshield is rated for lunar return reentries. Considering they were originally planning Grey Dragon, and that they're using PICA-X, an upgraded version of PICA which was used on the Stardust return capsule that reentered at even higher velocities, this seems quite plausible to me. It would need to be verified in practice of course, but assuming the engineer's modelling was up to scratch, little extra development work should be required.

[@shpratbananas7897]

When is the next episode in the starship series coming out? Love the videos by the way

[@Apogeespace]

TBD. Its not forgotten, but I felt inspired to make these 3 videos. So perhaps after this series, if not than soon after. Thanks so much for watching. Hopefully it comes out this year haha

[@robertclark1734]

Elon has said for the tanker version of Starship, i.e., without the large passenger compartment for 100 Mars colonists, and also with no reusability systems it might only weight 40 tons dry mass. So for the Apogee alternative not using the SLS, using just the Starship, the lunar flight might be doable with no refuelings! You would do the SuperHeavy/Starship in expendable mode, getting ca. 300 tons payload to LEO. But since Starship now ca. 60 tons lighter, call it 360 tons to payload LEO which could be propellant. This might be able to land a capsule on the Moon IF the capsule had its own propulsion to lift off all the way back to Earth.

[@user-db9pb2ww8d]

Hello! What does it meen on 7:30 - 7700 delta V? Is it about escape velosity from Earth, or wtah? Thanks.

[@jayk7169]

Great video. I often wonder whether SpaceX would develop an "HLS Shuttle" that would be similar to the HLS Tow Truck but would be designed to launch Dragon to LEO, thus eliminating the dependency on Falcon 9. The HLS Shuttle would have a truncated nose cone on top of which Dragon would be attached.

[@Apogeespace]

That would be cool! You may seem some similar stuff to that in future episodes!

[@skenzyme81]

Will be a while. There was no orbital crew until the 85th launch of the Falcon 9.

[@lazarus2691]

@@skenzyme81 That was because Crew Dragon itself wasn't ready. NASA only required 7 flights in a frozen configuration from SpaceX; they could have frozen at F9 V1.1 and stopped launching anything but CRS and done Crew Dragon around launch 25 or so if they'd wanted to. Starship doesn't need to wait for a crew vehicle to be developed in this proposal, NASA would probably be happy to let it launch Crew Dragon after a dozen or so successful launches in a fixed configuration.

[@steveaustin2686]

@@lazarus2691 So Crew Dragon could abort on launch at the top of the Starship variant you are proposing. Starship would take it too lunar orbit and bring it back to LEO for Crew Dragon to bring the crew down? If so, the crew would stay in Crew Dragon the whole way? Or would they undock and redock ala the CSM/LM? The crew would be constrained to 4 by Crew Dragon. The later SLS/Orion missions will have 6 crew. I know that the wiki lists Crew Dragon has having up to 7 crew, but that changed during development of the Commercial Crew contract. From the Dec 2019 Space Flight Now article with SpaceX CEO Gwynne Shotwell "After SpaceX had already designed the interior layout of the Crew Dragon spacecraft, NASA decided to change the specification for the angle of the ship’s seats due to concerns about the g-forces crew members might experience during splashdown. The change meant SpaceX had to do away with the company’s original seven-seat design for the Crew Dragon. 'With this change and the angle of the seats, we could not get seven anymore,' Shotwell said. 'So now we only have four seats. That was kind of a big change for us.'"

[@donjones4719]

There's one major problem with mounting Dragon to the top of a Starship. Once Dragon separates in LEO the Starship needs to return thru the atmosphere. For that it needs a rounded nose area covered with TPS tiles. It may be possible to use a mostly standard Starship with its nose 99% intact. Have only a few stilts poking straight up that Dragon will perch on. This isn't unprecedented in some rockets, the Soyuz rocket has an open latticework between the 1st and 2nd stages. Just imagining while I'm typing: No stilts thru the tiles. Instead have one large arm extending from the un-tiled side of the nose. This can be large and heavy, and will hold Dragon like a waiter holding a tray over his head. Once Dragon is deployed the arm can be ejected. Or possibly folded back & in, although that may require more development than it's worth. Intuitively it seems like it wouldn't be able to withstand any sideways forces during launch but a lot of engineering of transmitting loads thru beam structures results in counterintuitive structures.

[@charliespencer8740]

I certainly like the idea of having a shuttle / tow truck system that returns to Earth, as this gives the opportunity to load more cargo onto HLS for the next mission in LEO, not to mention allowing the return of lots of rock samples. However, this would probably require developement of a cargo transfer system. Perhaps they could just load something like shipping containers into HLS from a cargo Starship through the lift hatch, that way the payload doesn't matter. This could even be derived from the Starlink deployment system on Starship, where there is a magazine of containers that can be moved across. Your point of requiring minimal extra development is certainly required, though the tow truck HLS could easily be evolved for later missions.

[@Apogeespace]

That is a good idea. after the crew boards the HLS in LEO they could unload any cargo from a visiting cargo craft if they don't mind the wait. For the first mission you could obviously launch as much cargo as you want on board the HLS during its launch.

[@generalrendar7290]

I'd love to see a Sierra Space and Vulcan centaur solution. The Centaur 2nd stage seems tailor made for the tow truck method and for sustainable lunar space transit since it uses oxygen and hydrogen fuel. Recovery operations would be far more simple in Dreamchaser which already has a rear facing docking port. Shooting star seems to have a lot of room to be upgraded with additional life support systems if you use the un/pressurized cargo space for that. Sierra could still be used in your Starship tow truck scenario. Could you label me a space plane fanboy? Yes, but I will proudly carry that label! 🇺🇲

[@Apogeespace]

Keep an eye out for the next videos 👀

[@Shazzam40]

Dont forget that Sierra Space Dream Chaser is designed to reenter from LEO not from re-enty speeds of cislunar return trajectory. Also Dream Chaser has not been human rated. Its asking alot from the Sierra Team to change and redesign.

[@generalrendar7290]

@@Shazzam40 hence.... the tug. Returning without putting the tug in a proper orbit is the same as throwing it away. Not to mention the fact that the Dreamchaser can use its unused fuel in the craft itself to help slow down after the tug expends its fuel.

[@NGCAnderopolis]

@@Apogeespace where next video :(

[@Dularr]

How do you resupply the transfer vehicle?

[@chillwill8438]

Do you think in the future there will be LEO gas stations for commercial companies to use?

[@PeterAndrewsVermont]

Terrific again! Is there any reason the Starship fuel depot couldn’t also be used as the HLS Tow Truck, given astronauts remaining in the Dragon? That would simplify and reduce costs even further.

[@Apogeespace]

This would also work. I did mention the astronauts could move over to HLS after TLI. But if they remain in Dragon the whole time, having a more simple pusher starship or using the depot is better. I didn’t want to get into it in this video, but using the HLS does also allow this architecture to land if you refuel 3 more times.

[@Spruce_Cessna]

For the HLS tow truck can you just use a tanker starship?

[@elAJpr]

We don't have Starliner... yet... Nice video.

[@AshleighChevalier]

"Rockets don't spring forth from the ether..." lolol

[@acanuck1679]

Well done; it is a wonder to me that NASA keeps propping up SLS. It's main contractor, Boeing, has proven time-and-time again that it is unreliable and prone to milking NASA whenever it can. The costs of the architecture, together with the "throw the whole thing away each time" design, certainly seal the fate of SLS. The United States should pour more money into Starship and other alternatives.

[@peteforgiel3071]

Agreed 👍starship is an obvious choice. Sls was obsolete overbudget and behind schedule before it was even built

[@donjones4719]

NASA is tired of propping up SLS but Congress loves the Senate Launch System. As of now the only way of getting money for Artemis out of Congress is to use SLS. But IMHO this will fade after the Artemis III landing shows how capable the Starship system is and how ridiculous Orion looks docked to HLS. Hopefully Artemis IV will be the last to use SLS.

[@gravelydon7072]

There is another way to do the Starship HLS/ Dragon flight. Well actually two different. One would have the Crew Dragon sit atop the nose of the first HLS unit going to the Moon. As it would have the needed escape system for launch, no need for the Falcon 9 part. Yes they would have to be rated for the G levels of a Starship launch, but that likely would not be much of a change. Yes it would have to fill up at the Depot/Dock manned but that really wouldn't be a problem once that is worked out with the first few unmanned tries. Second would be to simply send up a new Crew Dragon to LEO if need be to bring them back from their return trip. That would give them a lifeboat so to speak and would be another level of redundancy.

[@davidreinhart373]

How vould they get to the aft docking port? Using hole in their heat shield? Or EVA?

[@alvianchoiriapriliansyah9882]

They wouldn't

[@Apogeespace]

The aft docking is port is not meant for the crew to access or tranfer through. It's sole purpose is to connect the dragon to the HLS starship physically, allowing the Dragon to face out during the TLI and NRHO entry burns.

[@chloekaftan]

it should be noted that if dragon performs an in-flight abort during the trans-lunar injection, dragon will very likely be stranded in space in a ballistic trajectory. those super-draco engines are not messing around with how much power they put out, so it must be imperative that space-x gives these engines the ability to feather its maximum potential output based on the starships thrust output. on top of that there must be a rocket on standby ready to rescue the dragon capsule in the event of an in-flight abort during TLI.

[@Apogeespace]

The superdracos can throttle ridiculously deep due to them being designed to land the capsule originally. It can “escape” very slowly and would be no more stranded than if Orion aborts from the ICPS. Not only can the superdracos already throttle enough to make this viable, the could also use 4 of the engines instead of 8 (2 pods instead of 4) if desired.

[@chrismoule7242]

You are right that redundancy is absolutely needed, and your vid covers what form it should take very well - as always. But on this occasion I think that your initial premise is faulty - and I think from what you say that you already know that. Your equation is that, because Congress has mandated NASA to provide redundancy for HLS, redundancy as a concept is, QED, needed and seen as desirable. Likewise, because has NASA has asked for redundancy in every project except SLS, they too must be proponents of redundancy, and SLS is perhaps some form of aberration. Actually, all this really indicates is that on the one hand Congress wants to give money to any firm that will earn votes and “local-to-the Congressman” spending & jobs, which basically means any US firm - or, better yet, a combination of firms - other than SpaceX, and on the other hand NASA knows that they will not get any more money for SLS, as it is already a tremendous across-the-board money earner, so Congress will never ask for any such redundancy, and will never agree to the extra spending: extra spending only gets agreed when Congress needs it.

[@lighthouseprj]

I think the most simple idea is making a disposing second Starship stage, which you can put a connector for stuff on it. This will also be usable for deep space missions so this should be developed and it is much easier than a landing starship. Up the second stage you put fuel for the Dynetics Alpaca HLS (if this one will be used) and Orion. I don't believe a capsule is a point of failure and Orion is tested and ready to use. Dynetics Alpaca HLS will be refilled before the crew come on board. (If used) Starship booster will always be reused and reusing this should be easier than reusing Falcon 9 first stage. The reason I see the Dynetics Alpaca moonlander as second HLS option is it's compactness and simplicity. Another option is adapt Crew Dragon for moonflights and put it on a Falcon Heavy. FH Should be man rated first.

[@spaceshipmania5476]

Nice video as always! I hope you will enjoy my models for a long time! 😁🚀

[@spacenoodles5570]

Great video! One bit of feedback:the red text (like at 20:33) is a bit hard to see, maybe because I'm colorblind

[@cube2fox]

How do you know it is red?

[@spacenoodles5570]

@@cube2fox I'm not blind, red just isn't as bright to me

[@cube2fox]

@@spacenoodles5570 Oh I thought you couldn't distinguish the red and green text. Guess there are different types of color blindness.

[@spacenoodles5570]

@@cube2fox no, I meant that the red text is hard to see on the dark background

[@mackenzieweber8138]

I'm not sure the Dragon Capsule would need its heatshield upgraded. I believe it was designed with both lunar return "Gray Dragon" and mars landing "Red Dragon" capability in mind. Yusaku Maezawa had originally intended to do "Dear Moon" on a crew dragon. edit: punctuation

[@lighthouseprj]

Heat shield of Dragon can have return from moon. With the Polaris Dawn mission later this year Dragon will make an extra hot landing, like they did with the Orion test in 2014..

[@Beldizar]

Minor error at 7:30, you suggest the Dragon capsule remain in orbit. I don't think it has the on-orbit lifespan to do that. It can only remain in orbit while attached to the ISS for extended periods, as it functions today. It would either have to go connect to the ISS to wait, or come back down and a different launch would have to go up later. Edit: you cover that at 11:00...

[@coreytaylor5386]

I believe they do have plans to upgrade it to be able to do such periods in orbit with the future Polaris missions, though that is a few years from now

[@Apogeespace]

Yes I make a note of that. Dragon would need to be upgraded to free fly longer or go dock to the ISS while it waits. In terms of space (and especially in terms of going to the moon) hurdles don't get any smaller and easier than that.

[@ashers.5856]

@@Apogeespace and there is already incentive to increase dragons on orbit time! With missions like I4 and the new Polaris Program, there is lots of demand for a longer free flight variant of Dragon. Sadly Dragon 2 has been put on a Manufacturing freezes as of recently, but I’d absolutely love to see a Dragon 3/Gray Dragon/FreeFlight Dragon once demand kicks up with the CLD and free flight era ever approaching

[@stillatwork]

@@Apogeespace why not just do the transfer of crew at the ISS? Launch HLS first, get if refueled in orbit, then dock it to the ISS, then launch dragon to ISS. Transfer crew and supplies. HLS leaves and heads to the moon, theb comes back and redocks and crew transfer back to dragon for landing.

[@alvianchoiriapriliansyah9882]

@@stillatwork ISS window & orbit limits the lunar exploration very dramatically

[@julianschnepp7168]

What about BFR or Starship That would have moon landing capability.

[@Apogeespace]

The HLS Starship (and hopefully eventually regular Starship) plan to have moon landing capability. NASA will use the HLS starship for moon landings. In this video however, I am only covering redundancy options for SLS Orion. Their job is to deliver crew to NRHO. So, although these two methods utilize a moon lander, and could be adjusted to land on the moon with more refuelings, we are not considering that.

[@davevann9795]

Is NASA sending out any requests for proposals or contracts for lunar habitation or rover?

[@Apogeespace]

They will be (hopefully) soon. They have said they are beginning the RFP process soon.

[@Bullhead_JW]

Why not use HLS as both the ferry and the lander? Theoretically that would cover everything. Or if just using it as a ferry, why not use a traditional Starship so that is can land directly on Earth from a free return trajectory?

[@Apogeespace]

That is definitely possible (and makes alot of sense). Why bring a lander all the way out to the moon and not land with it! It is possible with both of these architectures, it just requires 3 more refilling flights. I almost included that feature in the video, but I didn't want to distract too much from the purpose of the video, which is only providing redundancy to SLS Orion, which doesn't require landing.

[@Bullhead_JW]

Also, if using the tow truck analogy, why not use a SNC Dreamchaser in a crew config? That vehicle should be more than capable of the mission with no major redesign other than increased radiation shielding. Doesn't require propellant to land, and could potentially even return from low orbit of the moon with a modified cargo section that was given extra fuel tanks and engines. SNC also has it's docking port in the rear anyways, so it's designed to dock like that, which would allow access to the Starship with no extra docking/undocking maneuvers

[@waffletracktor]

Not 100% sure but i don’t think HLS Starship has enough fuel to do the injection, landing, and return on one tank. I also had the same thought about just using a traditional starship however as the traditional (crewed) starship isn’t part of the HLS contract it would probably count as extra development costs

[@spacenoodles5570]

What's the reason for a fuel depot? Could you not fuel the hls starship by several tankers directly? Does using a depot minimise risk?

[@Apogeespace]

In theory you could probably go directly from tankers. But the current Artemis plan calls for the Starship Depot. It will reduce boiloff and provide flexibility to tanker launch cadence.

[@steveaustin2686]

As Apogee said, the [DELETED] propellant depot is for managing the boil off and mostly to keep the mission Starship on the ground. So the [DELETED] propellant tanker launches first. Then up to 8 Tanker flights per Musk (maybe as few as 4 per Musk) refill the [DELETED] propellant depot. Finally, the mission Starship, Lunar Starship for Artemis III, meets up with the [DELETED] to refill. After Lunar Starship is at the Moon, SLS/Orion launch as Lunar Starship can wait up to 100 days for them to arrive. So Lunar Starship doesn't launch until the Dance of the Tankers is done. SLS/Orion doesn't go until everything is in place.

[@soctnights]

Great analysis. I fear the current global conflict will seriously derail the desire to return to the moon. NASA budget cuts and increased military spending could become more important. Could SPACEX's Lunar/Mars missions continue under severe budget cuts? Would Lunar missions remain a strategic priority if China/Russia push forward with plans for a manned Lunar base?

[@steveaustin2686]

Have some questions. For the HLS Ferry plan you laid out first, how is Crew Dragon staying in orbit during the lunar mission, but then you answered with an upgrade, likely in the trunk? It's roughly 6 days to the Moon and back and the shortest lunar surface mission is supposed to be a week. Crew Dragain can fly by itself for 10 days per NASA, so that leaves it at least 3 days short and that is without a margin. The longer missions are supposed to be up to a month long on the surface. Will NASA want to leave Crew Dragon or Starliner by themselves for that long? With only two US docking ports for Crew Dragon, cargo Dragon, and likely Starliner, with one used up for the crew on board, leaving them on the ISS going to be tricky. Also the ISS is on a 51.6 degree inclination and 7 of the 9 Apollo missions used a roughly 32.5 degree orbit, so will HLS even be on the same inclination as the ISS? Crew Dragon doesn't have a lot of return cargo space besides the crew, a cargo Dragon would be good for that, but the HLS Ferry (or [DELETED] propellant depot) would need another docking port. Musk has said that refilling the [DELETED] propellant depot can take up to 8 launches (Aug 2021 tweet in response to GAO report of 14 Tanker launches). Would you need to launch a new [DELETED] propellant depot for the HLS Ferry or could you use the one that refilled Lunar Starship that just left to the Moon? I'm thinking that [DELETED] could be reused for the HLS Ferry. The NASA contract for the Crew-7 to Crew-9 missions was $900M, so absent some details on that contract, you should use $300M for Crew Dragon. That $80M difference doesn't really amount to much compared to SLS/Orion. The Crew Dragon and Starliner can stay on the ISS for 210 days as they are shutdown and supported by the ISS. So would the Tow Truck method support the capsule like ISS would? You would likely need a longer fly by itself capability for aborts, so that has to be stuffed in their somewhere. Since the aft docking port is only for being pushed, it could be there I expect. The $2.94B HLS Option A contract is for two landings at up to 10 flights each. So that puts each HLS Option A Starship cost to NASA at roughly $147M. Even at your 4 flights per landing, you have $367.5M per flight to NASA. NASA noted in the Apr 2021 HLS Option A Source Selection Statement that SpaceX is funding over half of the HLS Starship cost, so I'm going with the NASA cost as the marginal cost. I wonder if your later videos will cover the [DELETED] propellant depot as a possible method for supporting capsules during a lunar mission. SpaceX had the GAO redact the info on [DELETED], so IF [DELETED] is just a propellant depot, then why redact the info to only then confirm its a depot in context. I think that is because the [DELETED] is more than a propellant depot. Making it a transfer station would make sense and there should be room as most of the depot is in the tanks that brought it to orbit. With an extension to the hull, if you can find room for three docking ports for capsules, besides a docking port for the [DELETED] propellant depot, then you can send up a Crew Dragon, Starliner, and later, a cargo Dragon. With 8 crew going up, you can leave one from each capsule to babysit them during the lunar mission. The other 6 go to the Moon and back like on the later Orion missions. Once the Ferry is back in LEO, then the crew unloads the samples and experiments into the cargo Dragon and return to the ground. At $1.47M each of the 9 flights (reusing the depot from the Lunar Starship launch), you have $1.323B. With $300M for Crew Dragon, $360M for Starliner, and ~$133M for cargo Dragon, the total cost is less than $2.2B. You also get a small station in LEO for the 2 crew to do some experiments and greater cargo return to Earth for less than the expected best cost for SLS/Orion. If Starship is less than $147M per flight and/or Crew Dragon back to $220M, even better.

[@steveaustin2686]

Forgot to add, that as I understand it, Orion is ridiculously redundant by itself as compared to other capsules. Apparently, any of the propulsion systems can get it back to Earth as they are independent of each other.

[@donjones4719]

I can offer one small answer to this long comment. Dragon has a 10 day endurance on its own *with a 4 person crew onboard.* Put into dormant mode with life support shut down this endurance will be extended. By how much? Only SpaceX knows, but it should be enough for the early Artemis missions. Otherwise, agreed. If the depot will indeed have a docking port/transfer node attached then Dragons can stay attached for as long as they do to the ISS.

[@jaceksiuda]

I've seen a concept (probably easy to google out) of Tow Trucking Orion, right from the launch. The idea was similar, Orion just provided means for Launch Abort System. This would complicate things only a little, require undocking for fuel transfer. Such concept has a big advantage not mentioned in the video: it will keep certain contractors in Alabama occupied, making such proposal acceptable politically.

[@Apogeespace]

Something similar to this in future videos. But as far as the good ol contractors remember, this video is about redundancy, not replacement. So they would still have all their same SLS Orion stuff going on.

[@donjones4719]

@@Apogeespace This camel is named Redundancy, not Replacement, said Apogee as it poked it's nose into the tent... 😄😇

[@nononono3421]

It will all be robots, remote-controlled with near real-time virtual reconstruction, and AI-controlled. Musk knows, it’s what Optimist is for. Try to calculate the cost of that scenario for fun ;) Great videos as always.

[@ericgribble9645]

I agree except for one thing. Normally crew return from the moon in a capsule with a heat shield capable of re-entry at above escape velocity. De-accelerating a Starship from escape velocity to low earth orbital speed to meet a crew dragon will take a couple of hundred tonnes of fuel. Unfortunately it will take a thousand tonnes of fuel to get this deadweight of fuel to the moon (from LEO) in the first place, there is a cumulative effect. This is why Elon is working on a superior heat shielding system for Starship that can survive the higher reentry speeds. Just free fall from the moon and re-enter at the higher velocity, do not transfer crew to crew dragon. I understand the crew dragon reasoning, it may be years before Starship is deemed safe enough for crew return.

[@steveaustin2686]

The Ferry plan is too make that Starship variant light enough and to carry little enough cargo, that it has the dV to reach lunar orbit and back without needing to aerobrake.

[@stonefreak5763]

20:30 you are writing, that "HLS Ferry" costs MORE than $340,000,000, I guess you mistyped (same with "HLS Tow Truck")

[@boostav]

Couple of questions. Why is the depot needed? Can't tankers fill HLS in LEO directly? Second, why can't the HLS ferry land directly on the moon surface thus not needing an HLS lander?

[@stanj7223]

Orbital refueling is next on Elon's hot list after they get to orbit. *Everything* hinges on it working. It's extra mass, but I suspect all of the orbital Starships (after these first few) will support orbital refueling. There's no solid reason for a depot if they're all hauling the refueling rigs; it's just connectors and cryo pumps. The only issue is the mating connectors. How do you make a gas-tight asexual connector? I think that's why they're looking at a depot with reversed-sex connectors. The only (eventual) Starships that _won't_ need orbital refueling will be the city-to-city hoppers, if that concept ever takes off. The HLS lander needs a slew of small motors about half-way up the fuselage for the moon landing. Elon and NASA suspect that the landing burn with Starship vacuum engines would toss up too much crud, endangering the HLS Lander (probably by digging a pit). Those motors are currently only in theory, and only on the HLS Lander. The HLS Lander will be a one-trick pony, never returning to Earth. It'll be a shuttle bus between Earth LEO and Moon landings. Other than the 'no abort' issue there's no reason why you need a separate Moon lander or HLS Ferry. The problem with Apollo 13 proved that the abort option that's only usable at launch is pretty worthless. Their only option once the TLI burn was completed was to abort around the Moon... they're lucky they didn't die. The Mars lander will be another beast entirely, and needs to survive aerobraking. It may also be only a shuttle between LEO and Mars surface (similar to HLS Lander), but that's years out. It'll need to survive all on it's own for over a year with no resupply or major repairs.

[@steveaustin2686]

Because there will be up to 8 Starship Tanker flights to fully refill a Starship. So a propellant depot will launch first for the Dance of the Sky Tankers, while Lunar Starship sits safely on the ground. That way it is safe if something goes wrong with the refueling and isn't sitting in orbit wasting resources. The SpaceX plan per the GAO report denying the HLS complaints will work like the following, with Musk's update to the Starship payload to LEO. Note, SpaceX had the GAO redact the info on the propellant depot, so it is likely something more than just a depot. First, the [DELETED] will launch to orbit. Up to 8 Starship Tanker flights will refill [DELETED]. Once [DELETED] is full, then Lunar Starship will launch unmanned to refill from [DELETED], before heading to the Moon. After Lunar Starship gets back to lunar orbit after the surface mission is done, it is basically out of propellant and can't return the crew to Earth. A Starship Ferry, if it is light enough, can make the LEO to lunar orbit and back to LEO trip, but won't have enough propellant for a lunar landing along the way. So to directly replace SLS/Orion, it can't be the Lunar Starship and needs to be a very light Starship, likely similar to Lunar Starship without legs.

[@steveaustin2686]

@@stanj7223 After Lunar Starship gets back to lunar orbit after the surface mission is done, it is basically out of propellant and can't return the crew to Earth. A Starship Ferry, if it is light enough, can make the LEO to lunar orbit and back to LEO trip, but won't have enough propellant for a lunar landing along the way. So to directly replace SLS/Orion, it can't be the Lunar Starship and needs to be a very light Starship, likely similar to Lunar Starship without legs. Starships can't leave Earth's orbit without refueling in LEO, so Mars Starships will have to do that, before heading to the Moon.

[@camerongarner9428]

Another great video. I highly doubt we will ever see Dragon involved in the Lunar architecture, however. Starship is designed from the outset to launch and land humans (though will only do so once a considerable number of unmanned flights are completed). It is already planned to fly humans on Starship as early as 2024. Also, since the HLS 'tow truck' won't land on the moon, wouldn't it be more efficient to have a 'standard' Starship variant, and use aerobraking to assist in entering LEO?

[@rkr9861]

I'm somewhat confused by your pricing for expendable Starship. $60M feels low. Figures like $30M, much like a modern airliner, are dependent on one purchase cost being distributed over multiple reuses, so an expendable Starship being only 30M more when vehicles like Dragon are well over $100M per launch even when reuse is considered... and that is a far less complex vehicle.

[@Dromfel]

I don't think expandable Starship is very desireble option for spaceX. If they achieve rapid and full reusability, there is always better way then waste a rocket. Just fuel it with tankers on the orbit a few times. SpaceX really need 100s of flights and landings to get NASA confident to put people inside and land with them. and the best way to do that? Tankers!

[@willdmann363]

I think that $60M is somewhat reasonable. First, after flights, both the booster and Dragon capsule need to be re-furbished, or at least inspected which involves rolling back to the hanger, cleaning and possibly replacing parts. This would lead to much higher costs than Starship (Only the booster in context of expendable upper stage) which, if it meets its expectations, will be rapidly reusable with minimum inspection. The upper stage, like stated in the video, will be very basic, which I can't see going over $50M. No need for a full interior and other systems like Dragon. Fuel costs will likely be >$2M for a launch, less if they produce their own. Overall, I think that $60M is a reasonable price for an expendable upper stage.

[@markschroter2640]

Does the falcon heavy have enough juice to get the orion to trans lunar orbit?

[@phoenixr]

It was explored. The biggest blocker is that it would need the ICPS as a 3rd stage - which the current SpaceX launchpads are not equipped to fuel (ports and hydrogen fuel). Also, it might need vertical integration which SpaceX is supposedly working on already for Nat Sec launches, but we haven't seen anything built.

[@steveaustin2686]

@@phoenixr Former Admin Bridenstine also mentioned that aerodynamics was an issue and was going to be looked at. Nothing was mentioned about how that worked out as far as I know.

[@markschroter2640]

@@phoenixr Cool, it was my understanding and I need to recheck, that the rocket could manage the weight but there were attachment issues needing an adapter, the fueling lines seem to be a minor problem. But then the SLS mock fuel up would make you question that assumption.

[@steveaustin2686]

@@markschroter2640 Yeah, the Orion, ESM, and ICPS are almost 58 tons, so a fully expended Falcon Heavy can lift that. That stack is longer than the new extended fairing that SpaceX is building, so that is where the aerodynamic concerns came from. The ICPS is only going to be used for 3 flights and then the 8.4m EUS is supposed to take over. I don't see the EUS flying on the Falcon Heavy.

[@markschroter2640]

@@steveaustin2686 I am curious but sadly don't know what any of those strings of letters mean. Orion I know.

[@zzubra]

8:35 The first mission architecture makes the potentially mistaken assumption that the ferry Starship could return to rendezvous with the same Crew Dragon that launched the astronauts. Because of the orbital dynamics involved, I suspect this will likely NOT be possibly, except under special circumstances. If the initial launches are to a high-inclination LEO orbit (to support minimizing exposure to radiation in the Van Allen belts), then the orientation of the orbit of the initial Crew Dragon relative to the Moon will change significantly as the Moon moves through its orbit. Only at certain points in the Moon’s orbit (once or perhaps twice a month) will it be energetically feasible for a returning ferry to reach the orbit of the original Crew Dragon. Unfortunately, the process of achieving rendezvous with the HLS in NRHO also involves some constrained timing. The net effect is that it may well prove impractical to rendezvous with the original Crew Dragon after returning to LEO. (Odds would be improved if a low-inclination LEO orbit was used, but this would increase radiation exposure from the Van Allen belts, perhaps by a factor of 10. It’s not clear if that would be acceptable.) Of course, all this could be remedied by launching two Crew Dragons (or comparable crew-rated spacecraft once they become available), and the mission would still likely be cheaper than using SLS/Orion. So, in general, this mission architecture is worthy of consideration, but might require an additional crewed vehicle that the video did not account for.

[@steveaustin2686]

As I understand it, the Apollo lunar missions were in Earth parking orbits of around 32.5 degrees, which I don't believe are high inclination orbits. The ISS inclination at 51.6 degrees is considered a high inclination orbit.

[@zzubra]

@@steveaustin2686 Generic definitions of what is or is not "high inclination" are irrelevant to the issue I'm raising. The real question is: Is the LEO staging orbit at an angle relative to the plane of the Moon's orbit sufficiently large to impose an unacceptable ∆V penalty once the orbits drift out of optimal alignment due to the Moon's movement? The inclination of the Moon's orbit relative to the Earth's equator varies between 18 and 28 degrees, with a period of 18.6 years. There was a maximum in 2006. During the Apollo landings, the declination would have also been near a maximum. There will be another maximum around the beginning of 2025, and a minimum around 2034. So, an Earth parking orbit around 32.5 degrees might only be about 5 degrees tilted relative to the plane of the Moon's orbit during a maximum, or perhaps 10 degrees tilt towards the end of this decade. (That's 0.09 to 0.17 radians.) For small inclination changes, changing the inclination of an orbit costs about V⋅𝜽 (really 2V⋅sin(𝜽/2)), where the orbital velocity V is about 7.8 km/s. So, the ∆V penalty for returning to an orbit that is 5-10 degrees off would be about 0.7-1.3 km/s. The penalty can be zero when the timing is just right (as would presumably be the case during trans-lunar injection), but would be that large on return if the timing is off. So, I guess the conclusion is that one COULD still rendezvous with the original Crew Dragon, provided either (a) one achieves just the right timing for mission duration or (b) one is capable of adding enough extra propellant to tolerate a very substantial ∆V penalty (which will get much larger than quoted for missions after 2030) or (c) it's deemed safe to enter the Van Allen belts from a lower inclination orbit. Thanks for providing the stimulus for further analysis.

[@steveaustin2686]

@@zzubra Or what if instead, you moved the Crew Dragon and Starliner to the right return inclination during the mission? Neither capsule can likely do that themselves, but what if their host spacecraft could? They don't have the life support by themselves for staying in orbit during the length of a lunar mission anyway, so something has to host them. SpaceX had the GAO redact the info on [DELETED] in their report (pg 27), but from the context that is left, it is at least a propellant depot. So IF [DELETED] is just a propellant depot, then why redact the info, to only then confirm its a depot in context? I think that is because the [DELETED] is more than a propellant depot. Having [DELETED] as a crew transfer station would make sense for missions when Starship is operation, but has yet to or can't get a manned rating. There should be room as most of the propellant depot is in the tanks that brought it to orbit. With an extension to the hull, you should be able to find room for two or three docking ports for capsules, besides a docking port for the Starships to attach to the [DELETED] propellant depot. Then you can send up a Crew Dragon, Starliner, and later, a cargo Dragon for transport of the crew up and back, and lunar cargo down. With 8 crew going up, you can leave one from each capsule on the [DELETED] to babysit them during the lunar mission. The other 6 go to the Moon and back on the Ferry, like on the currently planned later Orion missions. The only snag is you likely need one more Starship Tanker to add more propellant to the [DELETED] propellant depot after the Ferry has left, if the plane change is large. NASA has done some small propellant transfer tests on the ISS, but nothing near what a Starship Tanker would transfer. That is a possible sticking point, if NASA refuses to have crew onboard during large propellant transfers in LEO. Otherwise, the [DELETED] can do plane change over the course lunar mission, to be waiting with the capsules in the proper orbit for the return. Once the Ferry is back in LEO, then the crew unloads the samples and experiments into the cargo Dragon and then everyone returns to the ground on the capsules they came up in. The station experiments and lunar cargo return mostly on the cargo Dragon. At $147M* each of the 9 Starship flights flights (reusing the depot from the Lunar Starship launch), you have $1.323B. With $300M for Crew Dragon, $360M for Starliner, and ~$133M for cargo Dragon, the total cost is less than $2.2B. You also get a small station in LEO for the 2 crew to do some experiments during the lunar mission and greater cargo return to Earth, for less than the expected best cost for SLS/Orion. If Starship is less than $147M per flight and/or Crew Dragon drops back to $220M, even better. *The $147M per Starship flight is based on 2 landings for HLS Option A for $2.94B, with 10 Starship variant flights per landing.

[@zzubra]

@@steveaustin2686 As a point of reference, to make a plane change that requires a 1.0 km/s ∆V change, that implies the ratio of mass (dry mass + propellant) before/after the burn will be 1.3 (with Raptor engines) or 1.4 (with Draco engines). That means the more mass involved in the plane shift, the more propellant needs to be involved. So, yes, one could do a plane shift for the waiting spacecraft during the mission, but a significant amount of propellant would be involved, in general.

[@steveaustin2686]

@@zzubra Having to have propellant lift propellant, is the tyrrany of the rocket equation. With each Starship tanker bring around 150 tons of propellant, getting the propellant needed for a plane change should not be a problem.

[@heaposan]

I'm sure you are going to get to this option but surely the ultimate version of Starship HLS will launch with people on board. Will then refuel at depot, go to Moon, land then return to Earth. All the same ship that gets refuelled as required. No need for Dragon. Now this may take some time to get right but once there is a Human to Mars capable Starship the Moon version will use the same tech.

[@steveaustin2686]

That is the far future as Starship will have to prove very reliable for crewed launches without an escape system. Especially with the flip-n-burn, Mechazilla catch landing. Proving that reliability will take a LOT of flights. These plans are for the interim as Starship proves itself.

[@heaposan]

@@steveaustin2686 They will get a couple of hundred iterations of launch and catch pretty quickly with all the Starlink missions. How many Falcon launches did it take to gain human rating? Compare that with just one or two test landing of HLS on the moon.

[@steveaustin2686]

@@heaposan Crew Dragon has an abort system and Starship currently does not, so it is an apples to oranges comparison. Elon Musk has said that it would take hundreds of successful, operational flights before you could put people on board Starship launching from and landing on Earth. “'We’ve got to first make the thing work; automatically deliver satellites and do hundreds of missions with satellites before we put people on board,' Musk said, speaking Monday at the virtual 'Humans to Mars' conference" - CNBC Sep 2020 article Page 12 of the GAO report denying the HLS complaints lists Starship variants launching once every 12 days for Artemis III. Until Starship matures for a faster launch cadence, the hundreds of missions will take time. Starship also has to prove reliable enough to get a man-rating, which is possible, but not assured. IF Starship can't get a man-rating OR it takes a long time, something like the Ferry plan can provided manned missions in the mean time.

[@heaposan]

@@steveaustin2686 Sounds like Elon and I agree. Which is where I got my "couple of hundreds" figure from.

[@skenzyme81]

Will an anomaly on this flight finally kill the program? A successful launch is far from guaranteed.

[@alvianchoiriapriliansyah9882]

So do the SLS

[@themineosaur4675]

Edit: I'm an idiot lol, disregard my comment. Great video, only issue is that you aren't comparing like to like. Your starship ideas don't consider the cost of the lunar lander/getting it there, which SLS+Orion does. Starship will still be cheaper once you add that, but it'll be a little closer.

[@Apogeespace]

SLS+Orion price does not include the cost of the lunar lander getting there, that is separate.

[@themineosaur4675]

@@Apogeespace ah I'm dumb sorry I just assumed the lander went on SLS, should have done my research!

[@dalel3608]

And funding such an option is easy.. Take the SLS/Orion $3.5B/yr budget, and then split it; $1.75B/yr to SLS/Orion, & $1.75B/yr for the redundant system contract winner. Then have them fly once each a year, six months apart. If SLS/Orion says they can't fly for that, call bullshit.

[@dalel3608]

PS: Using the tow truck to slow Lunar Dragon allows you to use Dragons LEO heat shield, no need for upgrade there then.

[@dalel3608]

PPS: what's all this SpaceX only stuff, why no DreamChaser on tow truck. *flips table* 😂

[@dalel3608]

.. oh wait, “Episode 1”. *puts table back in place*

[@Apogeespace]

This is true, however, this now means that the return to LEO burn must work for safe crew delivery home, which is one of the problems that spawned the creation of the HLS Tow Truck method

[@jklappenbach]

SLS is doomed once Starship is operational. And if Elon is serious about a second version at 18m diameter (currently at 10m), there's no way that anyone will be able to compete. NASA should focus on building mining gear, surface habitat, toroid stations, etc.

[@DanielCJones]

May I remind you that SpaceX is working on Dragon XL for lunar cargo so there is the start of lunar tow

[@steveaustin2686]

Dragon XL isn't set up for an Earth return. It is a one way spacecraft, disposed of at Lunar Gateway.

[@alvianchoiriapriliansyah9882]

And NASA didn't give the authority to proceed with Dragon XL contract, technically it's still a paper vehicle There's a possibility that it will be replaced with Starship, since NASA already funded the HLS anyway

[@damitcam]

If two astronauts were stranded in nrho rn do any of us doubt elon would have a crew dragon on a fh tomorrow?

[@Jason-gq8fo]

I hope there are a bunch of frustrated nasa people watching things like this just wishing they could do it and not waste all that money

[@jndivetrips3765]

Ok Im going to stop you right there. This concept of using the Dragon has been proposed by people who assume Starship will never be human rated. I will remind you that SpaceX has 2 booked human flights on future Starships: a Polaris mission and dear moon. They wouldn't use Dragon, they'd use a Human Starship. The cost to fly Dragon on a F9 would be much more expensive than flying up a Starship.

[@steveaustin2686]

No, it is proposed for the period for when Starship is operational until when it could be man-rated. Since Starship has no abort system, it will need to prove reliable enough to be man-rated. Especially with the Mechazilla catch.

[@jonbong98]

They aren't going to do launches & landings with crew for quite a while, they will transfer crew via Dragon in LEO. No rush with human rating till their ready. The missions Will continue

[@forcemultiflier1746]

Imagine , If you will, all commercial space programs becoming 1 Space team ! T-E-A-M, Together Everyone Achieves More, !!!!

[@JoeJoe-gb2id]

Yo pls upload

[@theOrionsarms]

So basic question is what if congress cuts the funding of SLS, does a lunar landing program could work? Are some mistakes with this analysis, first Orion isn't bounded to SLS, yes is the only launcher that could send it to the moon, but Orion could be launched into the LEO with another rocket that will be human rated (I mean Vulcan Centaur witch would have exactly needed capacity for that), second exaggerated idea is that you need to keep crewed capsule into LEO when the crew travel to the moon, if the capsule is attached to the lunar HLS is Orion the smart thing to do is to travel to the moon with it attached and use it as return vehicle, which would eliminate need for a dedicated ferry, lunar lander can be used as space tug for Orion and that is all that you need.

[@steveaustin2686]

Former NASA Admin Bridenstein, said that you could launch Orion and the European Service Module (ESM) on one launch and the Interim Cryogenic Propulsion Stage (ICPS) on a second launch. You would need Falcon Heavy and Delta-IV and the ESM and ICPS would have to be modified for docking in space. They are mated in the VAB on the ground for SLS. Both the Falcon Heavy and Delta-IV would have to be man-rated and there are only 3 Delta-IV's left, all already set for NRO launches. The Falcon Heavy only launches from LC-39A and trying to recycle the pad for a second Falcon Heavy launch is not a trivial matter. The capsule would launch second, so you lose some propellant from the ICPS waiting on the crew to arrive per Bridenstein.

[@theOrionsarms]

@@steveaustin2686 you didn't understand what I said, basic idea is that you would have a large rocket into LEO (lunar starship),fully loaded with propellant and for a 27 tons Orion you only need to spend 60 tons of that propellant to transfer it to the low lunar orbit, and that would be all that you need, because Orion could stay into lunar orbit for short mission, and at lunar gateway for the long ones, and return with its own propellant to the earth.

[@steveaustin2686]

@@theOrionsarms So, the Tow Truck plan, but with Orion instead? The Tow Truck Starship is in addition to Lunar Starship.

[@theOrionsarms]

@@steveaustin2686 it's even better, you don't need a dedicated tow truck, lunar lander can be used exactly that in the original Constellation program.

[@steveaustin2686]

@@theOrionsarms Then you lose 27 tons of cargo on Lunar Starship. Will Lunar Starship even have 27 tons of cargo to give up? One way to make it light enough for the dV needed to get to the Moon, enter orbit, land, and return to lunar orbit is to not carry a lot of cargo.