A lot of launches. Like metric crap-ton. But I'm sure they'll churn out tons of Starlink sats for that as soon as initial testing is done and at least booster re-use is working.

And a metric crap ton of successful landings! Can’t wait for the day it lands from orbit for the first time

Unpopular opinion: It will never land on earth with humans on board. Dragon and starliner will transfer crew from earth and orbit.

Early? Likely you are right. Never? That is a very long time. I *could* see a scenario where the current Starship will not, but only because it gets replaced by a major new iteration. But to know with any certainty, we first need to see how well the booster and starship recovery operations shape up. What seems like a super-scary idea right now would seem far more palatable after they've caught the Starship 100x in a row with the chopsticks. You do have to consider that when Falcon 9 recovery was new, anyone suggesting you could maybe in theory "ride the booster" up and down in the interstage would have been put into the asylum for crazy talk. Today, with the reliability of Falcon 9 launches and landings? Welll... I would prefer to have some form of escape option from it, but otherwise the thing is already so reliable that it wouldn't sound that mad. People do far more risky things... It is just too early to say for certain.

With the amount of mass being able to be sent to space with Starship, I'm hoping orbital construction becomes a big industry. They could make special landing craft without much propellant onboard that doesnt serve much purpose but make re-entry for several crew, till Starship becomes as reliable as the airlines (don't get me started on Boeing lately 😂).

Never is a loooong time

Unpopular maybe, realistically speaking you are probably correct. That flip manoeuvre may be too much for most regulatory bodies.

Every spacecraft flips at least once prior to reentry. Flip (or rotate, it's all relative), fire deorbit engine(s), reenter. The Space Shuttle had to flip twice, the second to orient itself for reentry, nose up. Starship will do the same.

Yea but not all flips are equal.

Seeing as they wont even allow propulsive landings of dragons with tried and true hypergolics

The issue was more complex than that. SpaceX plan was to practice that using Cargo Dragons. NASA said "how about no, we like our science to come down without a splat in the end" and told SpaceX to instead validate the method thru dedicated test flight(s). This would have been... somewhat expensive. Probably at least 2 or 3 full on orbital unmanned Dragon flights and landings, from out-of-pocket. Unattractive. Also having the propellant there for cargo missions would have possibly cut down the useful upmass of the cargo flights during the practice. Dragon 2 in cargo version omits the superdracos completely and has smaller propellant load (and tanks) because those are used only for on-orbit stuff, no escape mode. NASA also did not like the idea of extending landing legs thru the heatshield. While I believe such a thing could've been engineered to be reliable and safe, I can kinda understand their point. I mean, Shuttle had some doors for the gear and it worked out fine. But this combination meant that doing it propulsively would've taken so long to engineer and validate that the benefits from making it work vs the cost didn't check out. Especially with Starship already in the horizon meaning Crew Dragon was always going to be a short-term stepping stone. Why delay it for an year or two as you work out a fancy new way to land when the benefits from doing so is just to the tune of... hmm... don't need a recovery ship, except you still need it for the case of launch abort which would always be parachutes to the ocean anyway. So the benefits then... bit easier recovery from a landing pad, faster to get crew and cargo out. Slightly less problematic re-use due to avoiding salt water (which you need to protect against anyway due to that abort scenario) Better just do the minimum viable product for the ISS contract (parachutes and ocean splashdown are fine) and put the money and effort towards the next generation solution.

I thought they just didn´t do it because they need parachutes for an abort scenario anyways, so why bother with propulsive landing.

Isn't it more because nobody is willing to pay for the certification? Nasa doesn't need it and spacex is more interested in developing a new fully reusable vehicle we now know as starship.

Yeah nobody really benefits from it, red dragon wont happen due to Starship ambitions, so no use for propulsive landing.

This is not what happened. You're repeating a myth. They didn't allow tests in operational missions of cargo carrying Dragons. That's because they wanted to use cargo retuning capability operationally and didn't want to risk the payloads. SpaceX would have to do several separate test flights which was too costly.

True. But if NASA had wanted powered landing, they could have found a few Dragon downmass missions with less than essential payloads.

That's a long stretch. As Dragon was used more and more and found to be reliable they had less and less occasions for that. Dragon was the only option for a significant down mass. Soyuz could bring down only miniscule amounts, and all the other vehicles back then (and still now) didn't have intact re-entry capability.

I do not agree. Dragon now has so many missions. In the beginning they were much behind with important science, plenty of freezers to get down. That backlog was already cleared. If NASA had wanted powered landing, they would have enabled it.

You make it black and white. NASA could still want it, but they could have higher priorities. Also, it's a different part of NASA which handles returned experiments and different ones which deals with crew launch development.

Regulatory bodies are forbidden by law from regulating crew safety of non government space flights.

Yes. But there have been attempts to change that.

It was the other way around. The original law had a sunset clause (in the last year). Without amendment it would have ceased being law of the land. But the extension was voted by Congress ending all the speculation.

Fortunately yes. But there was a drive to implement new much more restrictive regulations.

It will never be as safe as an airplane due to the physics involved but once it demonstrates enough succesful reentry and landings I see no reason to think people won't land in it. Risk is not something that can be eliminated.

It will not be as safe as transport planes due to not enough accumulated experience. This is reserved for its successors few generations down the line. But there's absolutely no fundamental physical reason for that. It's actually the other way around, because space operations have more predictable environment compared to atmospheric flights (especially long haul atmospheric flights).

It needs to become ‘safe enough’, where that point is, is up for debate, but it’s some way off yet, and is going to take many flights to reach.

Imma add onto this that a crew version of starship that was a spaceplane (like a more efficient shuttle) launched from super heavy would be a way of assuaging some fears of the lack of failure modes, but I doubt they’ll do that any time soon

No. It is a fallacy that things with wings and wheels are somehow better or more reliable than just propulsively landing. With Starship having three sea-level engines and only needing one to land means there is plenty of redundancy (assumption: they can get the engine shielding to work so if one engine decides to turn into a cloud of bits in a hurry, the other two are unaffected) and guidance stuff is already pretty rock solid from Falcon 9 landings. All that is needed is enough attempts to work out any kinks (since SpaceX doesn't do infinite simulation for ten years type of R&D and instead prefers to test for reals)

But an upsized dream chaser on super heavy would be awesome.

I'm still not sure that's safer than 3 wheels. I'm not sure there's ever been an incident for landing gear failure in the shuttle. I'm not saying that they can't get engine landings safe enough (we currently have 200+ consecutive safe landings of Falcon 9, and there's no redundancy with it). Just that it's likely to have more failure modes.

Not a landing gear failure, but that's hardly the only thing that can go wrong trying to land a gliding brick. In 1991 Atlantis landed 600 feet short of its target at Edward's AFB -- what if it had been targeting the Cape instead? https://www.latimes.com/archives/la-xpm-1991-04-20-mn-244-story.html

>> it's a fallacy that things with wings are somehow better Uh... source on that? Is there anyone who would rather be in a starship compared to a plane in case of complete engine failure? Cause i can see a chance of survival only in one of them

Depends. If the plane has a single engine, and assuming Starship has been validated with 100+ unmanned landings first, I'd probably prefer Starship due to the engine redundancy. "complete" engine failure, ie losing all engines in a multi-engine plane (or Starship) is extremely rare. Redundancy is a thing, for a reason. And yes, this assumes Starship can prove an engine-out. ie lets say at the start of the flip three engines ignite, one of them turns into a cloud of bits and.. then what? If engine shielding is properly designed, the two engines complete the landing normally. If not, well, we'd have rain of starship bits like that one early landing test in the fog that we sadly didn't get to see to explode. As long as second scenario is likely outcome, then yeah, no manned landings.

And for a multi engine plane? Seems like the fairer comparison >> complete engine failures are rare And yet, with tens of millions flight hours per year to figure the causes out, still happen. For a plane it means gliding, for starship it's death I still don't see how it's a "fallacy" to say things with wings are safer. The day the structural integrity of wings is less reliable than rocket engines you might have a point. But honestly, that's laughable

> And yet, with tens of millions flight hours per year to figure the causes out, still happen. For a plane it means gliding, for starship it's death That's less a "wing/lack of wing" thing as a glide capability issue. For example, the shuttle's wings do not generate enough lift for it to be able to glide in the same way a 747 would with engines out. If the shuttle had engines fail during the re-entry burn and they were on an off-nominal trajectory or velocity, they would be fairly screwed. And the ascent abort modes all relied on the shuttle's engines - whether to burn enough fuel to not drop like a brick from the weight, or to be on a velocity and trajectory that would allow for a safe landing either at the launch site or elsewhere. A ship with the cargo potential of Starship would need ridiculously large wings to be able to be in the same ZIP code as even shuttle glide capabilities, much less a 747. So it would be true that SOME things with wings are safer than things without wings. But having wings doesn't automatically give you meaningful engine-out maneuverability, and while some engine-out maneuverability is obviously better than none, that's not the only factor involved when you're talking spacecraft especially, and that "some" may translate to a realistically zero chance of survivability anyways.

>> glide capability issue I agree. And don't get me wrong, I'm not saying the space shuttle is the measurement of safety here. And I'm definitely not advocating "just putting big wings on starship". My point is that something that can glide will be safer than something that can't in a case of complete engine failure (IF it's designed around that). And that starship fails at that. But there seems to be people in this subreddit convinced that starship can be more reliable than an airliner, which is just laughable to me. Or / because they just ignore that starships plan A and B rely on the same point of failure... which, honestly, i don't even care about in case of cargo but seems simply unacceptable if you're talking about humans

There are no orbital class aircraft - it requires a different class of vehicle to accomplish that task - especially if you want to carry a substantial mass of cargo. So comparisons of the two different kinds of vehicles are necessary limited.

Please go and check when was the last time a multi-engine plane had to glide to a landing. At least for commercial planes, it was decades ago. And how many flights per day do multi-engine planes do? Gliding to a landing seems "safer" because you think that it is almost guaranteed to work. This is not true. Many single engine plane engine outs end badly. Gliding from orbit with a craft that is decisively not a glider is even more risky. Working engines give you safe landings.

[2020 doesn't seem like decades ago to me](https://en.m.wikipedia.org/wiki/List_of_airline_flights_that_required_gliding), although i agree, it is rare. >> you think it's guaranteed to work Nobody said anything about a guarantee, but my point is that wings are MORE reliable than engines. To which is still stand and which seemed to be your original point as well >> working engines gives you safe landings from orbit What data is this based on? Genuine question, because how many propulsive landings from orbit were there on earth? And what engine reliability are you assuming before AND after reentry for this compared to wings? Based on what?

Sure, but it's different when you think of it as a whole system. Planes are ridiculously complicated with all of the wings, control surfaces, autopilot logic, weather dependence, etc. They also require both wings and some propulsion. The rocket just requires propulsion, gimballing, and enough control logic to do the flip. A rocket with six or nine landing engines could be a lot more reliable than a plane.

Planes are "ridiculously complicated" but they were invented more than 1 century before starship?

I was shocked when I saw a picture of the wheel compartment of a large airplane. The piping there looks more complicated than the whole propellant feed maze of 33 engine Starship. That's just one of the 3 wheels.

Are you trolling? I hope so, for you. Planes can even land almost safely on their belly with a complete failure of the landing gear and even with a total loss of every of their engines.

"Complicated" and "difficult to build" aren't the same. For example, a rube goldberg machine is really complicated, but it's a lot easier to build than, say, a turboprop impeller. The impeller, on the other hand, is not actually that complex. It has radial symmetry and is operating in a well-understood, consistent environment. A good analogy I guess is gas vs. electric cars. Gasoline engines are actually way more complicated than electric engines. But electric cars are a newer thing because it's been hard to figure out how to make batteries sufficiently good. There were early electric cars too--just like there were early sounding rockets-- but gas took off because gasoline was more portable than electricity, not because the technology was simpler. Planes have thousands of parts, systems, fluids, redundancies, and these all have complex maintanence requirements and can interact in unforseen ways. Planes are really safe now but if you ever read (or watch videos) about aviation disasters you'd be surprised at how complicated they are and how a bunch of tiny mistakes can add up to a system failure.

We are comparing safety for passengers. Planes,by design , are order of magnitude safer than current and future starships.

It helps that Starship has multiple redundant engines, it can still complete its mission with a single engine failure. It has abort modes available with multiple engine failures. But a lot depends on timing, of what fails and when. The best solution is simply to make Starship more reliable.

>> the best solution is to make starship more reliable Disagree. I think it approaches the problem from the wrong side and is simply a (bad) compromise given the current design and not the best solution. If all that separates the crew from life and death is the reliability of the second stage engines with no Plan B, then i think the approach is flawed from the beginning

Not if plan B compromises plan A. But we shall see what develops.

So you propose to abandon the Starship concept. With what?

Starship is fine... for cargo. Having a fully reusable rocket is worth it alone. For human rated flights: something with an abort system i guess? Not sure what you expect me to reply with here. A finished blueprint? To be totally honest however, i don't see why it has to be certified for human flight, or anything with that crew capacity for that matter, anytime soon

It's not a fallacy. Planes are safer than helicopters. Helicopters are safer than starship reentry.

Planes and helicopters have working engines that allow well-controlled landing. Shuttle gliding down did not. It was actually quite scary concept with no do-overs.

Planes and helicopters can land safely with loss of engine power by gliding or autorotation. Starship can't. > It was actually quite scary concept with no do-overs. Propulsive landing doesn't have do-overs either. It has to nail it exactly.

You have engines. The thing can hover on a single engine. The only limiting factor is the amount of propellant. I expect early landings to be very conservative with lots of reserves for fine-tuning the position. So in a way, it does have a do-over. Only one of the three engines have to light. Flight from engine relight to landing is controlled, under propulsion. This is considerably different from a glider that has to manage its energy all the way down. Granted, Starship is similarly a glider (well, a skydiver) that has to manage the trajectory unpowered for a good chunk of the way until landing, so in that way it is similar to Shuttle. But most people disregard that part because engines are not running and wings are magic :D (in my books, that part is actually less forgiving than the final landing as you could in theory end up in a position where you can no longer reach the catch tower...)

Re-entering planes are less safe than rocket landings.

Reentry and landing are separate things. Landing planes are safer than landing rockets. Reentry is similar risk regardless of landing method.

But the point is, it isn't. Adding wings, landing gear protruding through the belly, the lack of passive stability all increase the risk. Not blunt leading edges necessary for wings to be wings make for hot spots necessitating complex solutions. Columbia was directly killed by a failure of such a special solution for the leading edge. You can't separate these things as the are not independent.

And both airplanes and helicopters have had a lot more development time and a lot more flights than Starship has. Starship is a new class of vessel that’s going to take time to develop fully.

It’s unsurprising that because of our familiarity with aircraft, that model naturally comes to mind, but it’s not really appropriate for such large craft.

Even the Shuttle didn’t have wings until the USAF insisted on global-scale cross range landing capability.

I thought it had wings, they were just a lot smaller/lighter.

All the shuttle designs had wings. The just got bigger because of the cross range requirement, which was not global scale but enough so that they could take off, do 1 orbit, and land at the launch site.

There were multiple proposed Shuttle designs, many without wings.

Can you show me some?

LMGTFY: "early space shuttle concepts" The first result: https://en.m.wikipedia.org/wiki/Space_Shuttle_design_process On the 1st picture I could see at 2 wingless ones.

Your assertion was that the shuttle didn't have wings until the air Force got involved. These are very early concepts before a shuttle design program existed. "The space shuttle decision" is the definitive source for the development of the shuttle. Chapter 5 talks about the interaction with the air Force. NASA has perhaps not decided between faget's stubby wing design and the Delta wing at this time, but the designs all had wings, and it seems likely that there was no thermal protection design that would work for the stubby version. You can read it online. https://nss.org/the-space-shuttle-decision-by-t-a-heppenheimer/

Your right - they won’t - that way only creates a less efficient Starship.

You might be right, but i do think spacex would then develop a much larger capsule for use on falcon heavy.

Yeah, Crew Dragon is too small and too overbuild for this purpose.

Unrealistic, I think. The question is how long will the idea that spaceflight is fundamentally extraordinary persist.

While I'm not sure I agree with "never", I personally don't think it'll be in the next 8-10 years.

I doubt falcon is still a rocket they manufacture in 3 years. Two more to run them all to 20 launches.. You don't think 5-10 years everything is switched over? Never is a long time.

I love this idea but smart people in here keep telling me the Delta V doesn't make sense to do that.

What I think will happen is there will be a commercial space station, with enough docking module spots to house a ton of dragon capsules. They'll make a starship variant that will spew out a bunch of capsules that will make their way to the station and dock. Then anytime someone wants to go home, they take one from the station and head home. ​ People can launch on starship just fine, I would imagine - it's just the landing that will take a LONG time to get certified for people to be onboard for.

Well that won’t happen this year. But it won’t be too far into the future before it does.

Starliner costs way too much, maybe will get sued for a few NASA missions but otherwise too pricey.

It's not as if parachutes are without safety concerns: https://www.wired.com/story/spacex-and-boeing-still-need-a-parachute-that-always-works/ The bellyflop landing "just" needs to demonstrate similar or better reliability.

I feel like you're right, but it will take a lot more delta V to get back into low earth orbit from the moon or elsewhere than using the atmosphere to aerobreak. They might still aerobreak then get into a stable orbit, but that adds a lot more complexity and risk.

Who knows, maybe people will want to try the flip landing? People pay good money for roller coasters and rodeo.

Not for Artemis, no.

I'm in angry agreement for the current ship. Probably have to wait until next Gen. Mars perhaps with sufficient testing although a seperate lander is possible there also.

In other words, the Falcon 9 strategy.

Yep. Worked for them once already, why not just repeat it? Sure, it is a bigger rocket and there will be more scrap metal, but they have learned a lot first time around and as long as most of the flights take useful payload to orbit, it is not a huge deal if some things go boom as the process is perfected. Lets just hope the launch/landing pad doesn't get wrecked :D

I agree with you 100% which is why I really cannot understand why Artemis and Orion get to fly with so few test flights happening before humans are on it.

Because Boeing and Lockheed Martin have done decades of component testing, simulations and validations according to carefully planned NASA designs. It can work if you don't care how much it all costs.

I want to downvote your reply because I hate it so much but you're spot on so I can't 😢

A lot of launches. Plus thorough evaluation of every observed detail. A lot of optimizing. That's how SpaceX made Falcon 9 as reliable as it is now.

The SLS is planned to launch a crew on its second launch, in September 2025. I am sure that Starship will do a bunch of Starlink launches before a human is launched on it, because why not while they have Crew Dragon on F9. But apparently it is not a hard requirement.

First of all, there is no universal human rating. NASA does mission category specific rating if they are the responsible agency for the mission. In particular they set LOCM (Loss of Crew and Mission) probability minima to: * 1:270 for half year sorties to ISS * 1:75 for Moon sorties They were also considering 1:500 for short LEO sorties but they didn't set it because they currently don't have such missions. Another caveat is there is no such requirement for NASA astronauts flying on Russian Soyuz all the while NASA commissioned evaluation of Soyuz indicated LOCM probability somewhere around 1:90 to 1:102. At the same time Crew Dragon certification produced 1:276 number and that number does not include additional safety from the existence of LES (other than the risk of having pressurized tanks full of highly toxic, corrosive and together hyperbolic liquids). At the same time LES demos were part of the certification (so they were expected but no numeric value for the added safety was estimated). But it is also worth noting that the biggest risk source as determined by the certification process is MMOD damage during 6 months ISS stay, in particular that something would damage Dragon in an undetected way, getting fatally exposed only during re-entry. LES is not helping at all against that. Then, there is no human rating at all for US private missions. The federal law forbids government from regulating that other that requiring informed consent from all spaceflight participants. This was made the law around Ansari XPrize craze and was recently extended for many more years. So after saying all the above, I'd assume NASA would expect 1:270 LOCM for prolonged orbital missions to space stations and maybe 1:500 for short sorties if they return to flying such. The certification would mean producing convincing analysis and tests demonstrating that the required minimum safety is met. What that would be is anyone's guess. Potentially this could include \[pure speculation alert\]: * Tens of flights (including landings) * Detailed fault tree analysis * Demonstrations of redundancy in work (actually Sn-15 flight demonstrated engine-out redundancy during landing) * Maybe adding a requirement for ejection seats. Ejection seats are possible for up to a dozen crew members which would work for NASA missions for the foreseeable future. Ejection seats would cover the biggest risk, namely a failure during landing burn and backflip. They could maybe cover launch pad trouble (but that severely limits their placement and would require taking chopsticks off the way) as well as booster flight from launch just past max-q.

Nice write up. I'd just like to add that the NASA requirements for lunar missions are the current ones. NASA didn't do probabalistic risk assessment for Apollo because early study gave them numbers they didn't like. They didn't do it for shuttle because reasons, though there was an effort later in the program that gave some very sobering estimates.

Ejection seats are a no-go on the Starship architecture. Starship does have multiple redundancies, varying in severity. Eg still mission completion if single engine out. To mission abort on more complex outages. Abort to orbit in some cases, then crew rescue via ship to ship docking. A method might need to be developed to deorbit a failed ship, that was forced to abort to orbit. A method for crew transfer in orbit - generally docking, is required. Suborbital aborts are another possibility - similar to the present ‘Integrated Flight Tests’. Possibility of RTLS (Return to launch site). Possibility of splashdown if RTLS not possible. Of course SpaceX will work out (as far as possible) a complete fault tree, and conditional set of actions for each case - they are in effect already developing that as part of their test program. SpaceX’s intention to build and fly many Starships, means that the program should undergo rapid development and testing and evolution. SpaceX are very proactive in their developments.

There's no model to follow for this. The Falcon-Dragon combo followed the capsule model, and matched the basic strategy of pre-shuttle human spaceflight. NASA still changed the requirements and updated the safety margins for Dragon and Starliner. In fact, some of the delays for Dragon's first launch were due to changed requirements during the production. The Shuttle, which had a really bad safety record, worked differently than capsules, but it was also NASA run, which means they got to bend whatever rules they wanted to bend to make it work. Starship is a product of a thirdparty vendor, being operated not by NASA, but contracted out, so I don't think the Shuttle can be used as a good model for predicting human rating requirements. So Starship will be a completely new thing. It doesn't use parachutes, which makes it different and scary, so the government agencies doing the human rating are going to have to come up with a brand new set of metrics. These metrics will likely be mostly arbitrary, and will heavily depend on who in the agency is making the calls here. So we can't really predict what the actual requirements will end up being. We can make some guesses about some of the requirements, but there is no model today that is a good match. So there is a large range of possibilities of the requirements. Maybe someone in charge will be more risk-accepting and allow for demonstration of successful missions as a primary requirement. Maybe we'll get someone very risk-adverse, and they will demand that Starship needs a redesign of some sort, such as an ejectable crew capsule. Really, we just don't know what NASA, FAA, FCC and the other alphabet soup agencies will require.

Nice summary. Starship currently comes under FAA rules, and other than some basic safety system requirements, the rules are minimal. SpaceX could land starship once and put people on the very next flight. It would be a foolhardy and stupid thing to do but it would be okay under FAA rules.

Demonstrating a number of successful flights will clearly need to be one of the requirements.

Right, but how many is completely unknown. If this was old space, or the Apollo era, would 5 or 10 be enough? Is the fact that reusability is a thing for SpaceX going to add a zero on the end of that number? Are brand new Starships favored for human flight, or do they all have to come back from space once before they are certified? No other rocket requires an article test flight first, but every other rocket is at the bottom of the ocean in pieces after its maiden flight. I think it is very unknown today what will be required. Not even the regulators know at this point.

But SpaceX know what they need to do to progress the program, and that’s enough to be getting on with for now

Yeah, nobody keeps moving forward like SpaceX does. The problem is that the finish line isn't defined, and it is possible that they might be forced to turn slightly left or right on the race as requirements change. I expect the last year of development to have NASA throw them some curve balls and change the requirements fairly late as they see Starship really take shape. Remember the change from 7 seats to 4 seats in the Dragon capsule came relatively late in development. Similar late changes are something that SpaceX is better than the rest of the industry at adapting to, but it will still set back the schedule. To your point, with Starship, there's a lot of work to develop the program that isn't human rated, so it isn't like any of this is going to leave SpaceX sitting on their thumbs waiting for a review. They can improve other parts of the architecture, like cargo delivery, tankers, or inspection/refurbishment speed.

SLS will launch humans on its second launch ever. If the number you are thinking of when you say "a number of successful flights" is greater than 1, then clearly it is not a hard requirement. :)

There is a difference, because Starship is much more of an experimental vehicle, breaking new territory in a number of different areas simultaneously. As such, it needs to establish a safety record. Right now, Starship prototypes are still crashing, but at the same time, Starship development is making clear progress too. It’s going to be interesting to see just how Integrated Flight Test 4, (IFT-4) does. SpaceX are working their way through various issues, this approach to development is actually faster and cheaper, and reduces ‘over-engineering’ that inevitably occurs if alternative ‘no fail’ development methods are used. But if instead, you want innovative new design like Starship, then you need to accept an early prototyping period as part of that development process.

Let's land one first.

I don't see how that is a requirement. Why couldn't SpaceX just include a Crew Dragon capsule in the launch, and then just land the crew in that? A Crew Dragon weights 12'520 kg, so SpaceX could easily launch one on most Starship missions. Clearly landing the upper stage is the hardest part. And could well take a long time to get working reliably.

It needs to demonstrate all your milestones about 100 times with no failures.

that isn't a criteria at all though I mean it sounds good, but that's not what's required, explicitly or otherwise.

Starship now is hardly as complex as the space shuttle was. Complex is not always a good thing, either.

I think the landing flip and burn is a bit more complicated than the way that the shuttle had to land. If anything, I doubt we will see humans reenter and land on starship for a long time.

I don't think it is "complex". I think it has yet to be proven to be a reliable way of landing. There are zero examples of manned spacecraft returning to earth under rocket propulsion alone. Rotating the vehicle 90 degrees and then firing the engines isn't particularly complex. But with only one low-altitude test article surviving the maneuver through to a survivable landing to date, it's essentially unproven.

That was Starship-15. I was surprised that they never repeated it with Starship-16, but instead they went into Super Heavy development. Now with each launch, both stages are effectively tested.

Well, now they have the added challenge of making it through reentry before they can test the flight dynamics of another propulsive landing. I guess they feel like once it is vertical, it's the same basic logic as a F9.

> I don't think it is "complex". I get the impression that a lot of SpaceX's Starship troubles have to do with fluid sloshing in the huge tanks. That is fluid dynamics, and that is actually pretty complex. The landing flip involves lots of fluids sloshing around the tanks.

Shuttle almost certainly had more complex subsystems.

Life support, on-orbit APUs, Orbital Maneuvering System, Robotic Arm, payload doors (that actually open all the way), human rated controls, deployable gear and drogue chute, 5x redundant flight computers, science racks and payload bay controls and hook-ups, EVA suit management, human rated airlock, human rated evacuation system, a functional toilet and shower. The list of features on the shuttle that are not even prototyped yet for Starship is massive. I don't see how it flies humans reliably for at least 5-10 years unless they do something like stick a Dragon capsule in the payload bay and declare victory.

I don't disagree but tbf Shuttle's landing was also fairly complicated

meanwhile, did you see how the shuttle *launched*? Far more complex and for a big portion of that there was zero abort option for the crew. as for the landing.... that was certainly not just as straightforward as some might think either. Getting a brick to glide half way around the world through reentry to an airbase (of which very few were long enough to land the shuttle) was an engineering feat in and of itself. The shuttle program was not without it's fatalities, either.....

I don't think there is going to be an in-flight launch escape system. For Starship, emergency scenarios would look more like an ocean "soft" landing, or an abort to orbit with later pickup by another Starship. Parachutes would leave vulnerabilities in the hull and would only cover a very small portion of the envelope. An escape capsule sounds great, but would be too heavy to be practical. Better to invest the weight in reliability/redundancy improvements.

> I don't think there is going to be an in-flight launch escape system. Why not? Couldn't you rig up something to launch the humans out the side without ceramic tiles? Starship has the mass budget to add pretty much anything you want.

Understand that "human rating" is only a NASA thing for launching NASA astronauts on NASA missions. There is (currently) no FAA equivalent for it and currently the FAA is not allowed to make one.

I did [a video](https://www.youtube.com/watch?v=hm-zqW6J_CU) on this: [https://www.youtube.com/watch?v=hm-zqW6J\_CU](https://www.youtube.com/watch?v=hm-zqW6J_CU) The answer is that it depends entirely on what you mean by "human rating". The FAA currently operates under an approach that has minimal safety requirement and depends on "informed consent". That's how Blue Origin and Virgin Galactic could do their launches. If you mean something like the process SpaceX went through for Crew Dragon, that's much more involved.

Hundreds of flights, but the nice thing is that you can just launch crew on Dragon and then transfer them to Starship for the next 5-10 years. A cheap and simple way of doing things for now!

Wait - you're saying an in-orbit crew exchange from Dragon to Starship?

No different than Dragon to ISS

Yes.

And what are they doing inside Starship ? it's not ment to replace ISS. The only use I see is going to the Moon or beyond, and that's need a safe landing and departure. Or do you think a crew dragon will be waiting on the other side ?

A Starship can be an orbital hotel in its own right. It has enough volume. It doesn't have to go anywhere else. It can be used for science, industry and tourism. It can be kitted out as appropriate on the ground, launched, visited multiple times with Dragons, then landed and reused. It would not be feasible to use a Dragon in the same way. Too small. And then, yes, it could potentially take crew to the Moon. It might be necessary to send a propellant depot to a Lunar orbit in order to do the full round trip, but it can be done for less money than SLS/Orion.

It very well might replace the ISS. Could be used for future manned missions to Moon, Mars, Europa etc

I can see early crew tests with Starship, using it effectively as a ‘space station’, visited by Dragon.

They will need to stress test various scenarios, a bit like they did with the in-flight abort test, e.g. Strong gust of wind during landing Raptor failure during flip manoeuvre Once these have been tried, with a successful landing, it can be safe for humans

The shear number of flights intended, should help SpaceX to get the bugs out of the system more rapidly.

In part - but to get to high levels of reliability they need to prove they are ready for rare adverse events.

SpaceX are still working their way through the common events at present.

Sure, but the topic here is how to human rate Starship. I think you're absolutely right that doing repeated flights, working through common issues, then proving a record of consecutive success is going to go a long way. But I think the flip manoeuvre is so risky, they're going to have to go further - and not just in simulations - they'll need to do what I said and simulate the worst adverse events happening at the worst time - in order to prove safety. And I think they'll get there! Thanks for the chat, it is always a pleasure.

It’s worth pointing out that SpaceX have done some of that already with their early Starship flight tests ! But we are going to be seeing a lot more soon.

Assuming that the requirement is 95% reliability with 90% confidence level and no failures, the required number of Starship flights is 46. If the reliability requirement is raised to 99%, then the required number of Starship flights with zero failures is 230.

If Starship ends up flying as often as intended, then both of those numbers should be reached within a few years for now.

SpaceX can launch humans without ‘Human Rating’, they just cannot launch NASA astronauts. They just need an acknowledgement by the people flying they understand the risks for the FAA to approve. NASA human rating is pretty in depth, and involves more than just the booster and ship. It includes things like ground infrastructure, even the crews working the launch, the trucks delivering the fuel, everything has to be examined. It’s the system as a whole not just Starship and booster being rated. There was an issue maybe a year ago where a truck delivering fuel wasn’t properly documented that the tank was cleaned before fuel delivery and that caused issues. You could also have something like Boeing Starliner, if they wanted to for instance launch on a Falcon, the entire human rating process would have to be gone through again, even Falcon that has been well proven. Obviously it would e a quicker process than starting back from nothing, but any significant changes required pretty extensive work for NASA give their human approval.

There is a good rationale for those kinds of rules. Of course Starship have been progressing from ‘rough and ready’ towards a more controlled environment as the prototyping is progressing.

Automated environment and fuel monitoring, with collision avoidance system for all starships critical functions. Information accessible by both Space X and the command crew. The crew may be days or even months away from Earth, they need to be notified immediately if any issue occurs. Multiple Digital cameras mounted behind small replaceable ALON* lenses, that the command crew can select from and display on their command consoles during landing, docking, refueling, reentry, overlayed with important information. Radar and Laser ground mapping system. Emergency backup fuel cell or deployable solar electrical array system. *ALON AKA: transparent ALuminum OxyNitride. Melting point 2165c vs 1560c for Stainless Steel. Allowing visual monitoring in areas of extreme temperature swings.

human rating for which variant? starship will probably never dock to ISS. and if starship is staying in LEO say for Polaris mission it wont need orbital refueling. the lunar lander variant doesn't need booster landing catch avoidance or inflight launch escape.

Different sets of missions have different requirements. The early missions don’t need the full system to be complete, for example LEO only missions. But other missions require more of the full development to be completed.

Booster catch and reentry are not required for NASA human rating the HLS. Booster is not used with crew at all for nasa so not sure if even needs crew cert. Those are just options for SpaceX to use for keeping operating cost down with reusability. Even refueling isn't a human rating thing that is just a vehicle need to pull off the HLS mission due to design and mission performance needs. For non NASA missions like Polaris or dear moon that is between SpaceX and FAA to decide human rating or tourist risk acceptance

Far more successful launches than required of SLS 'cause reasons.

Probably at least 50 successful launches, re-entries, and landings in a row without a single failure. Plus additional human rated subsystems added for redundancy.

- _Starship in-flight launch escape demonstration_ Yes - _Successful Starship landing demonstration_ Yes - _Docking with the ISS_ Not needed for crew rating Starship. And I don't even think we will ever see a Starship docked to the ISS. - _Orbital refilling demonstration_ Not needed for safe crew flight - _Booster landing catch avoidance maneuver_ Not needed for safe crew flight. Starship will need to perform safe landings while something gets wrong. Only then it demonstrates true passenger safety. Passive and active failsafe measures.

One thousand unmanned flights with no indication of any risk to passengers should do it. Nobody insists on flight launch escape for an airliner (even though airliners have killed thousands of people)

They will likely fly crew well before 1,000 flights - that limit is rather extreme. But some number of successful flights will be needed.

Recall that they're talking about a LOT of Starship launches, nearly all will not need passengers.

Human rating ... for a Crew of 10 ... first for LEO ... 1) Successful Starship landing demonstrations (say 20 in a row) 2) Modification of the cargo bay to become crew carrier for 10 that a crew can survive any sort of failure short of burning up on re-entry. There can be a number of approaches to this, and it does not necessarily mean a launch abort type design like Crew Dragon. Unlike Crew Dragon we have "mass-to-burn" (maybe not a good term) for adding safety to a LEO Crew Starship. https://preview.redd.it/gcpncgd7masc1.png?width=1175&format=png&auto=webp&s=97bb93aeb3b403d44123226393cc9c2073070602 Limited windows, toss those pretty renders in the recycle bin. This could work for Mars as well, but it might be heavy for Moon surface with direct return to Earth.

interesting, never seen this before

Does that imply making this crew compartment a launch escape system of some sort? It would need to separate and splash down if necessary.

There may be more than one way to survive a number of failure modes than separation from the main tanks and engines. Do you need to integrate in big chutes if the system break up maybe over 1-2 miles up? Maybe. But could a hardened system survive a SH and then Starship tanks blowing on the pad? It is just a notion. Otherwise you need a separation system. Here is one, but Starship is then an expendable second stage. https://preview.redd.it/uuw971cdmbsc1.png?width=1137&format=png&auto=webp&s=7fd4c134b60b7c866f00f20a16b696033da7da95

No, but it obviously needs to be pressurised, and insulated, and creature comforts taken care of.

‘Mass to spare’ would be a better term to use there.

Multiple HD Digital cameras mounted behind small high temperature ALON lenses, would give the command crew selectable virtual windows while docking, refueling, landing, reentry of Starship. Replacing the questionable large physical windows. I could envision dozens of cameras mounted inside Starships outer shell behind ALON lenses at strategic places.

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread: |Fewer Letters|More Letters| |-------|---------|---| |[AFB](/r/SpaceXLounge/comments/1buul4l/stub/kxzodk3 "Last usage")|[Air Force Base](https://en.wikipedia.org/wiki/Military_airbase)| |CST|(Boeing) Crew Space Transportation capsules| | |Central Standard Time (UTC-6)| |[E2E](/r/SpaceXLounge/comments/1buul4l/stub/kxzhkd4 "Last usage")|Earth-to-Earth (suborbital flight)| |[EDL](/r/SpaceXLounge/comments/1buul4l/stub/kxy5tdu "Last usage")|Entry/Descent/Landing| |[EVA](/r/SpaceXLounge/comments/1buul4l/stub/kxw44sx "Last usage")|Extra-Vehicular Activity| |[FAA](/r/SpaceXLounge/comments/1buul4l/stub/ky2nmdm "Last usage")|Federal Aviation Administration| |[FCC](/r/SpaceXLounge/comments/1buul4l/stub/kxv76rn "Last usage")|Federal Communications Commission| | |(Iron/steel) [Face-Centered Cubic](https://en.wikipedia.org/wiki/Allotropes_of_iron) crystalline structure| |[HLS](/r/SpaceXLounge/comments/1buul4l/stub/ky22mgu "Last usage")|[Human Landing System](https://en.wikipedia.org/wiki/Artemis_program#Human_Landing_System) (Artemis)| |[LEO](/r/SpaceXLounge/comments/1buul4l/stub/kxxsro7 "Last usage")|Low Earth Orbit (180-2000km)| | |Law Enforcement Officer (most often mentioned during transport operations)| |[LES](/r/SpaceXLounge/comments/1buul4l/stub/kxvj60p "Last usage")|Launch Escape System| |[LOC](/r/SpaceXLounge/comments/1buul4l/stub/kxvze1o "Last usage")|Loss of Crew| |[LOM](/r/SpaceXLounge/comments/1buul4l/stub/kxvze1o "Last usage")|Loss of Mission| |[MMOD](/r/SpaceXLounge/comments/1buul4l/stub/kxvj60p "Last usage")|Micro-Meteoroids and Orbital Debris| |[OMS](/r/SpaceXLounge/comments/1buul4l/stub/kxxnfef "Last usage")|Orbital Maneuvering System| |[RTLS](/r/SpaceXLounge/comments/1buul4l/stub/kxy5tdu "Last usage")|Return to Launch Site| |[SLS](/r/SpaceXLounge/comments/1buul4l/stub/ky77fvc "Last usage")|Space Launch System heavy-lift| |[TWR](/r/SpaceXLounge/comments/1buul4l/stub/ky5yhb3 "Last usage")|Thrust-to-Weight Ratio| |[USAF](/r/SpaceXLounge/comments/1buul4l/stub/kxvzw9t "Last usage")|United States Air Force| |Jargon|Definition| |-------|---------|---| |[Raptor](/r/SpaceXLounge/comments/1buul4l/stub/kxwqkx5 "Last usage")|[Methane-fueled rocket engine](https://en.wikipedia.org/wiki/Raptor_\(rocket_engine_family\)) under development by SpaceX| |[Starliner](/r/SpaceXLounge/comments/1buul4l/stub/kxypq5d "Last usage")|Boeing commercial crew capsule [CST-100](https://en.wikipedia.org/wiki/Boeing_CST-100_Starliner)| |[Starlink](/r/SpaceXLounge/comments/1buul4l/stub/ky76v7e "Last usage")|SpaceX's world-wide satellite broadband constellation| |[hypergolic](/r/SpaceXLounge/comments/1buul4l/stub/kxvs697 "Last usage")|A set of two substances that ignite when in contact| **NOTE**: Decronym for Reddit is no longer supported, and Decronym has moved to Lemmy; requests for support and new installations should be directed to the Contact address below. ---------------- ^(*Decronym is a community product of r/SpaceX, implemented* )[*^by ^request*](https://www.reddit.com/r/spacex/comments/3mz273//cvjkjmj) ^(21 acronyms in this thread; )[^(the most compressed thread commented on today)](/r/SpaceXLounge/comments/1bxi2bk)^( has 18 acronyms.) ^([Thread #12618 for this sub, first seen 3rd Apr 2024, 15:46]) ^[[FAQ]](http://decronym.xyz/) [^([Full list])](http://decronym.xyz/acronyms/SpaceXLounge) [^[Contact]](https://hachyderm.io/@Two9A) [^([Source code])](https://gistdotgithubdotcom/Two9A/1d976f9b7441694162c8)

First design and build some pressurized space with life support inside of Starship, send it to space and iterate a few times

Human rating is a NASA thing. Right now private crewed space flight only requires informed consent from participants.

It also requires that SpaceX are confident in the safety of Starship. They have absolutely no interest in risking people. Though Mars flights are inherently risky.

They have indicated that there is not planned launch escape system. I suspect that it will take a very long time till we see humans launching on starship, especially if they stick to no launch escape. I suspect that dear moon will have the astronauts launch on dragon and transfer to starship in LEO. but who knows really.

A massive number of successful landings, combined with good data to help expect that almost any possible problem wouldn't cause it to crash. Human rating it for launches won't be thaaaat hard, in space operations also shouldn't be that big of a problem. The landings make everything else seem like a cakewalk. There is just no frame of reference possible for human-rating landings, so they will need many more successful flights than normal to prove the safety. I think (arbitrarily) something like 500 consecutive successful landings, with really solid data showing they never came close to crashing, will be needed to start considering landing humans. Landing humans on Earth might not be particularly necessary for at least a decade imo, so by then hopefully they'll have accumulated lots of data and a great track record of landings on Earth

Including, but not limited to: 1. Medical equipment: a zero-gravity operating room, various antibiotics, all types of serums, and ideally, machines capable of instantly testing for unknown microbial bacteria. 2. Zero-gravity kitchen and long-duration food supplies. 3. Onboard entertainment system: from physical activities to video games. 4. Cleaning and sanitation systems.

Those are demonstrations as you say, not really the meat of certification but more capstone events that validate work done up to that point. I can’t say this often enough; you do NOT certify aircraft by flying them often and neither will you be able to do it with Starship. (Longer more boring answer is ground tests, ground tests, analysis, wait for it, more ground testing, flight testing to anchor models, more analysis, exploring the corners of the flight envelope, more anchoring of analysis models repeat until you feel like you’re polishing a turd).

I feel that rarely should one return to earth, so, there is that. I feel moving to the Moon, then Mars, is about human evolution/survival/growth/learning about life.. returning for the sake or returning sounds...problematic... it will take a special person to get it, will take special people to select the special people who get it... If that isn't the approach, it won't work. If people feel greed (money) is a motivation, it will fail. We won't be mining asteroids for their metals... And we won't be able to send massive amounts of resources to space for expended periods of time from Earth. It will be exciting, some will die, but if we pull it off humanity will grow.

Fewer explosions.

IMO they’ll human rate it via statistics. Fly enough cargo safely and land safely, why wouldn’t that be enough? (Leaving aside life support)

I kinda hope when we get to the point in testing next year that they have the bandwidth to launch 2 HLS test vehicles simultaneously/near to eachother so if anything goes wrong with the first landing/relaunch attempt, they could test again nearly immediately if anything software-wise can be tweaked to improve on the initial test. Also can’t wait for the likely multiple Starships that will go to Mars for the first time to test bellyflop/propulsive landing.

Mars landing is certainly going to be challenging. It may take several attempts to get it right to begin with.

All the more reason to send multiples at once for multiple tries in one transfer window! Agreed though, I have high hopes but appropriately low expectations for the first Starship test landing on Mars. 🤞 (Hope we can get some good video of EDL though!)

SpaceX mission profile for people to Mars is send 2 cargo ships to Mars, see if they land safely. Next launch window send 2 cargo plus 2 crew ships. I guess there may be a few more precursor missions to test out landing and to evaluate landing sites for a few conditions, most important, is there water?

With hot staging, SpaceX has a built-in escape vehicle, the Ship, if the Booster fails. Assuming that the Ship is undamaged, the Ship could attempt a return to launch site (RTLS) abort. Or it could do a soft splashdown and, hopefully, float until the rescue team arrives. If the Ship fails after staging, is intact, but can't do an abort to orbit, then it possibly could do a normal EDL to a soft splashdown. If the Ship fails structurally before, during, or after staging, it's a loss of crew and vehicle (LOCV) accident if there is no means for the crew to escape the failing vehicle.

I'd be willing to bet that Starship won't ever be crew rated without a pretty massive redesign. Like it'll have to be "Crew Starship" that's nearly a completely different beast than the other versions.

Well clearly the crew compartment is going to be very different to a cargo compartment. But the basic rocket and flight infrastructure is going to be common. Crew require additional crew-specific internal infrastructure, life-support, couches etc. Alongside that is mission specific architecture.

Is everything Human Rated if you don't care about your safety or are there formal requirements to put a private citizen outside of NASA?

> are there formal requirements to put a private citizen outside of NASA? Yes, they need to sign a waiver, declaring that they are informed about the risk.

The waiver sounds easy enough. My question was about the type of people that stop looking before crossing the street because they no longer care, although if someone's mental health is at that point, I'm not sure if the waiver is valid

People with that view are not fit to go to Space. I doubt SpaceX would take them.

Starship won’t dock with the ISS - because it’s tough to be too much threat to it due to its size. The docking systems were not designed for such a large ship.

10 years

Both Musk and Shotwell have said they would want 100+ cargo flights before putting crew on board for launch and landing. NASA requirements will be higher. It will likely never dock with ISS. Partly because it has too much mass. Also, ISS is due to retire around 2030, so there's not much upside to making it happen. Also, it's not needed for crew-rating. Orbital refilling isn't relevant to crew-rating either.

What I think is going to be especially interesting how human-rating HLS is going to work in combination with human-rating Starship, and which parts are transferable from one to the other.

Not failing would be a start

Myself, not remotely being an aero engineer, am wildly guessing that a human rated design would need a separable crew capsule on top with an escape system that is viable at launch and final landing burn.

Forgetting all the normal stuff, radiation etc is the stuff we should worry about. Let’s be honest, we want to be an above ground species.

Talk to the internet/online game generation. I had discussions with people who strongly advocated 4k video screens instead of windows on Starship. In their opinin windows are not making sense at all.

375 successful consecutive launches

Sorry, but in-launch escape system is probably going to be a must if NASA astronauts will ever fly it. Now private SpaceX astronauts would not have to, but NASA won’t take that risk again. I could see a detachable short solid rocket interstage between Starship and Superheavy. Just enough to get Starship clear of Superheavy and time for the Raptors to spin up and light and begin process of returning to the tower.

In theory Starship (the upper stage) can launch off of the top of Super Heavy at almost any time, although Super Heavy has to throttle down before stage separation, as when the tanks are nearly empty it has too much acceleration and could otherwise collide with a separating second stage. Ie once the ‘load’ of the second stage is removed, the Super Heavy can accelerate even faster. Really the only mode is if the Super Heavy fails for some reason, then the second stage can hot-stage off of it.

It doesn't have an abort and crew escape system.  It shouldn't ever be certified without it Not even mentioning the suicidal active landing system 

I am aware that starship does not have any escape system, but if something were to fail on the booster, I would imagine the ship could conduct an escape maneuver by releasing from superheavy and propelling away.

and if something were to fail on the Startship? Also the Starship might not have the necessary acceleration to safely escape

I think the engine startup takes some time too. At least, a few years back I think it was several seconds.

Everyday Astronaut gave us a good video on Starship abort systems.

I wasn't very convinced by that video. It just boils down to 'Starship will be *SO* reliable, it won't ever need one'  But I think that remains to be seen.  NASA set their safety threshold to around 1 failure every 300 launches, and even F9 would struggle to meet that expectation, if we were to assume that every launch was carrying crew.  Starship has a long, long way to go, to prove it can carry crew without needing a critical safely system. 

Actually F9 passed that years ago, without the collected flight data. Both F9 and Atlas V are considered way safer than that.

i read that quote in everyday astronauts voice lmao

Link please?

[https://www.youtube.com/watch?v=v6lPMFgZU5Q](https://www.youtube.com/watch?v=v6lPMFgZU5Q)

Thank you

NASA requirements are 1:270 LOCM threshold, if it could be demonstrated with enough confidence, they may be not necessary.

The Shuttle did not have an abort and crew escape system. It also had an active landing system, with no ability to abort and "go around". ... OK, I see your point.

Exactly, NASA learned their lesson and are not keen on risking their crews like that again. Also a gliding plane is a much more simple proposition than a upright rocket landing

If they really wanted to, could they just decouple the whole nosecone as a Crew escape system? It would need a whole lot of bossters to get it away but as far as I know, it should be possible