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If they were trying something genuinely new - like falling out of orbit and making a propulsive upright landing of a wingless booster - then some skepticism wou

If they were trying something genuinely new - like falling out of orbit and making a propulsive upright landing of a wingless booster - then some skepticism would be justified. But what's new in Starship?

ceejayoz 5y ago
Propulsive landing of an orbital stage is pretty new. (You can make an argument for Soyuz's just-before-landing rockets, but it wouldn't be a fair one.)
- Dylan16807 5y ago
  > Propulsive landing of an orbital stage is pretty new. It is, but those are largely separate features. Each half of that combo has been done, and combining them doesn't cause any massive engineering conflicts.
  - macintux 5y ago
    No one has, to my knowledge, de-orbited a spacecraft ready to launch again immediately, which is where Musk thinks Starship is headed. That’s a big jump.
    - Dylan16807 5y ago
      That is, yes, but jumping that hurdle doesn't really matter if the landing is propulsive or not.
- JulianMorrison 5y ago
  Okay, I'll grant you that. Not a huge step from what they already do, but it is a step.
  - macintux 5y ago
    Given the uncertainty around heat tiles (and the impact on rapid turnaround) plus the sheer size of the rocket, it seems like a huge step to this ignorant observer.
  - vanattab 5y ago
    Orbital flight vs suborbital flight is a bigger step then you might think. For orbital flights the vehicle is traveling at least 28,000 km/h where as to reach 125 miles above Earth, a suborbital vehicle only needs 6,000 km/h. This can dramatically effect the survivability on reentry. Orbital and sub orbital flights are very different.
ncallaway 5y ago
> But what's new in Starship? The planned recovery mechanism (the aerodynamic fall, with a very late righting maneuver and landing) is still quite new. They've successfully tested it once (which is great!), but the Starship concept really hinges on that being an extremely high reliability maneuver. I would argue that, until SpaceX can demonstrate that landing maneuver is high reliability, that the Starship concept isn't proven. I say this as a massive fan of Starship, and someone who is extremely excited by the promises of Starship of they come to fruition.
- humanwhosits 5y ago
  They can take the mass penalty of performing a large re-entry burn to reduce heat-load and land falcon9-style. It would mean _much_ less mass to orbit, but the cost savings of reusing the vehicles would still be there.
  - JulianMorrison 5y ago
    Except that one of the Starship's big new things is refuelling in orbit.
modeless 5y ago
Nitpick: the booster does not achieve orbit. If it did it would need a heat shield like the upper stage. What's new in Starship? Rapid turnaround. Catching the returning rocket with the launch tower. A durable heat shield that needs zero refurbishment for back-to-back flights. The sheer number of engines on the first stage and the volume of engine production needed for that. Orbital refueling. The landing flip maneuver. There is a lot of new stuff in Starship, and not all of it is proven yet. Personally I think the biggest remaining risk is the heat shield. I'm no expert, but my speculation is that there will be several reentry failures, and refurbishment will limit turnaround speed for a long time. I've also heard a lot of people saying that orbital refueling will be very difficult. I'm also worried that landing failures will wreck the ground support equipment. And I think it's very unlikely that the reliability of the whole system can ever be good enough for the airliner-like earth-to-earth passenger service that SpaceX has proposed. All that said, I'm very much in agreement with the article that NASA needs to radically change their future plans, because while Starship is not completely proven, it is clearly derisked to the point where it's going to be revolutionary, even if some of the above risks prevent the total potential from being realized. HLS was the first time NASA showed that they realize this, but they are still doing tons of stuff outside HLS that makes little sense in a Starship world.
- prox 5y ago
  Even for some reason Starship can not return in its early development, it still triumphs SLS by a wide, wide margin.
- ncmncm 5y ago
  Rapid turnaround is not demonstrated. Nor is it even, in fact, planned, in any real sense. I.e., to be clear, there is no evidence that they have any idea how to achieve rapid turnaround of a Starship orbiter. (Superheavy is a different story.) All this turns on the design of the heat-shield tiles. Those we have seen are basically the same as on the shuttle. Each individual tile needs a great deal of personal attention before and after each use, including squirting in some goo that will boil off on the next flight. Many will need to be replaced, each flight. So, turn-around time is weeks, minimum. More probably a month or two, or three. It is conceivable that a future version of Starship will have a heat shield that needs less attention. Maybe a fabric shroud in place of tiles, over most of the hull, will turn out to be practical. If that happens, it might get possible to turn around a re-entered Starship faster. But that will require entirely new development not obviously begun. I will be happy to be proved wrong. Despite all of the above, even without quick turnaround or even re-usability, Starship is obviously overwhelmingly superior in every conceivable way to Artemis/Ares. NASA has the unenviable chore of trying to unload that turkey on some commercial contractor to get out from under the obligation to pour ever more treasure down its gaping maw, endlessly. If NASA succeeds in selling it at a penny on the dollar to Marietta, and leaving Marietta to try to find someone, anyone willing to pay for even a single hull, we can all breathe a sigh of relief.
deleted 5y ago
[deleted]

ceejayoz 5y ago

Propulsive landing of an orbital stage is pretty new. (You can make an argument for Soyuz's just-before-landing rockets, but it wouldn't be a fair one.)

Dylan16807 5y ago
> Propulsive landing of an orbital stage is pretty new. It is, but those are largely separate features. Each half of that combo has been done, and combining them doesn't cause any massive engineering conflicts.
- macintux 5y ago
  No one has, to my knowledge, de-orbited a spacecraft ready to launch again immediately, which is where Musk thinks Starship is headed. That’s a big jump.
  - Dylan16807 5y ago
    That is, yes, but jumping that hurdle doesn't really matter if the landing is propulsive or not.
JulianMorrison 5y ago
Okay, I'll grant you that. Not a huge step from what they already do, but it is a step.
- macintux 5y ago
  Given the uncertainty around heat tiles (and the impact on rapid turnaround) plus the sheer size of the rocket, it seems like a huge step to this ignorant observer.
- vanattab 5y ago
  Orbital flight vs suborbital flight is a bigger step then you might think. For orbital flights the vehicle is traveling at least 28,000 km/h where as to reach 125 miles above Earth, a suborbital vehicle only needs 6,000 km/h. This can dramatically effect the survivability on reentry. Orbital and sub orbital flights are very different.

ncallaway 5y ago

> But what's new in Starship? The planned recovery mechanism (the aerodynamic fall, with a very late righting maneuver and landing) is still quite new. They've successfully tested it once (which is great!), but the Starship concept really hinges on that being an extremely high reliability maneuver. I would argue that, until SpaceX can demonstrate that landing maneuver is high reliability, that the Starship concept isn't proven. I say this as a massive fan of Starship, and someone who is extremely excited by the promises of Starship of they come to fruition.

humanwhosits 5y ago
They can take the mass penalty of performing a large re-entry burn to reduce heat-load and land falcon9-style. It would mean _much_ less mass to orbit, but the cost savings of reusing the vehicles would still be there.
- JulianMorrison 5y ago
  Except that one of the Starship's big new things is refuelling in orbit.

modeless 5y ago

Nitpick: the booster does not achieve orbit. If it did it would need a heat shield like the upper stage. What's new in Starship? Rapid turnaround. Catching the returning rocket with the launch tower. A durable heat shield that needs zero refurbishment for back-to-back flights. The sheer number of engines on the first stage and the volume of engine production needed for that. Orbital refueling. The landing flip maneuver. There is a lot of new stuff in Starship, and not all of it is proven yet. Personally I think the biggest remaining risk is the heat shield. I'm no expert, but my speculation is that there will be several reentry failures, and refurbishment will limit turnaround speed for a long time. I've also heard a lot of people saying that orbital refueling will be very difficult. I'm also worried that landing failures will wreck the ground support equipment. And I think it's very unlikely that the reliability of the whole system can ever be good enough for the airliner-like earth-to-earth passenger service that SpaceX has proposed. All that said, I'm very much in agreement with the article that NASA needs to radically change their future plans, because while Starship is not completely proven, it is clearly derisked to the point where it's going to be revolutionary, even if some of the above risks prevent the total potential from being realized. HLS was the first time NASA showed that they realize this, but they are still doing tons of stuff outside HLS that makes little sense in a Starship world.

prox 5y ago
Even for some reason Starship can not return in its early development, it still triumphs SLS by a wide, wide margin.
ncmncm 5y ago
Rapid turnaround is not demonstrated. Nor is it even, in fact, planned, in any real sense. I.e., to be clear, there is no evidence that they have any idea how to achieve rapid turnaround of a Starship orbiter. (Superheavy is a different story.) All this turns on the design of the heat-shield tiles. Those we have seen are basically the same as on the shuttle. Each individual tile needs a great deal of personal attention before and after each use, including squirting in some goo that will boil off on the next flight. Many will need to be replaced, each flight. So, turn-around time is weeks, minimum. More probably a month or two, or three. It is conceivable that a future version of Starship will have a heat shield that needs less attention. Maybe a fabric shroud in place of tiles, over most of the hull, will turn out to be practical. If that happens, it might get possible to turn around a re-entered Starship faster. But that will require entirely new development not obviously begun. I will be happy to be proved wrong. Despite all of the above, even without quick turnaround or even re-usability, Starship is obviously overwhelmingly superior in every conceivable way to Artemis/Ares. NASA has the unenviable chore of trying to unload that turkey on some commercial contractor to get out from under the obligation to pour ever more treasure down its gaping maw, endlessly. If NASA succeeds in selling it at a penny on the dollar to Marietta, and leaving Marietta to try to find someone, anyone willing to pay for even a single hull, we can all breathe a sigh of relief.

deleted 5y ago

[deleted]