SpaceX’s Superheavy/Starship successfully launches
Superheavy/Starship lifting off today
Early this morning SpaceX successfully launched its Superheavy/Starship heavy-lift rocket on its third orbital test flight.
The flight achieved almost all of its test goals, and far exceeded what was accomplished on the previous test launch in November.
First, Superheavy appeared to operate perfectly through launch, putting Starship into its correct near-orbit trajectory. The hot-fire stage separation, where Starship begins firing its engines before separation, worked as planned for the second straight time. Superheavy then refired some of its engines so as to target its correct landing zone in the Gulf of Mexico. As it approached the ocean surface, however, it started to tumble, and though some engines appeared to light for the landing burn, something went wrong and the stage was lost.
Next, Starship continued on its coast phase, during which engineers apparently tested opening and closing the payload doors as well as demonstrating a propellant transfer between two tanks. It also appeared that the engineering team was testing a variety of orientation modes for Starship. First it flew oriented stable to the Earth’s horizon. Then it appeared they placed the spacecraft in barbeque mode, where a spacecraft is placed in a steady roll in order to evenly distribute the heat on its surface.
For reasons not yet explained, the team cancelled the refire test in orbit of its Raptor engines. As the orbit chosen was low, the atmosphere still slowed the spacecraft down so that its de-orbit would still occur over the Indian Ocean.
As Starship started to descend it appeared its flaps were working successfully to control its orientation. It also appeared the heat shield tiles were working, as shown in the picture below. As Starship entered the thicker part of the atmosphere however, some tiles could be seen flying away from the ship and the spacecraft began to tumble. At an altitude of about 65 kilometers signal was lost.
Starship entering the thick part of the atmosphere.
Overall this was a very successful test launch, far more successful than the two previous attempts. As has become expected for this company, every problem was solved from the previous test, with any failures this time new ones farther down the road. Superheavy did its entire job getting Starship into orbit. It only failed at the very end of its flight, in doing its landing burn to make a soft vertical splashdown in the Gulf of Mexico. Based on this superficial analysis, we should expect Superheavy to achieve that soft splashdown on its next flight.
Starship also completed almost all of its objectives. It did not however do an engine relit in orbit, for reasons not yet explained, and failed during re-entry. SpaceX will have to review the data now to determine what went wrong during that re-entry, and what changes are required to fix those issues.
Elon Musk recently said the company hopes to do about six more test launches this year, about every two months, similar to the test launch pace it was achieving for Starship in ’20 and ’21. We shall see. The FAA under the Biden administration has been reluctant to issue launch permits with that speed, as had been done during the Trump administration. Other factors might also delay the next launch, including new lawsuits from a number of activist groups.
My prediction now is that it will be no less than three months before the next launch permit will be issued, placing the next test launch sometime in June.
Because this launch correctly placed its payload in its planned orbit, I consider it a success for my annual launch count of successful launches. Superheavy/Starship is in this sense now an operational orbital rocket!
The leaders in the 2024 launch race:
25 SpaceX
10 China
3 Russia
3 Rocket Lab
American private enterprise now leads the rest of the world combined in successful launches 29 to 19. SpaceX by itself leads the rest of the world combined 25 to 23.
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Congratulations to SpaceX . . .
. . . and to private enterprise.
Impressive as hell!
The only ones who do not like this?
The CCP Chinese and the Russians I would suspect.
I think they will now have to embrace the power of DEI policy and what can be accomplished.
Cotour: You left out the Biden administration and the left. They hate the fact that some Americans are actually accomplishing something, without any consideration of sex, race, or ethnicity.
This is why Joe Biden made no effort to visit Boca Chica on his recent trip to Brownsville. He doesn’t want to give any support to SpaceX, and if he had his way Elon Musk would be in prison for daring to criticize his policies.
The Ship stage appeared to make the transition from an initial nose-first attitude to tail-first, as would be required for a de-orbit thrusting.
Even after no reentry burn, it apparently failed to reenter the nose-first attitude that would be required for actual reentry, resulting in instability and breakup.
I am familiar with aero-forms that are inherently stable, and which would naturally assumed a nose-first attitude once atmospheric drag was encountered, but apparently the Starship is not so designed.
I would suspect that Elons interpretation of DEI would be very heavy in ability, merit, dedication and excellence and not the current definition of the “give me because I deserve it because I am in a class of oppressed people, and you owe it to me” DEI.
I think I am going to have to make another distinction now and include the Subjective version of “DEI” along with the “progressive movement which is not about progress at all and the “woke” movement where it is better to be awake rather than “woke”.
I will take this opportunity and post this SIGMA3iOC post that discusses the Founders who when you study them a bit you come to understand that they were true PROGRESSIVES of their day who structured our country in an Objective form where freedom can result in people like Elon Musk accomplishing what we are all witness to here today.
However, the self-described “DEI” “progressives” of today being entirely Subjective and not about freedom in the least but are about compulsion and forcing people to speak and act as THEY command. And that must ultimately be by force if you choose to resist.
The Founders who Elon and co. can trace their success directly to today were so Objective and advanced in their thinking that they chose instead of a Theocracy, even though they were followers of the words of Jesus to create a Republic based Democracy. Truly PROGRESSIVE men of their day.
“The Founders fundamentally recognized that a King, a Religion or a Government would always be a direct threat to the individual’s freedom. What you do not bestow you cannot take away. BRILLIANT and unassailable!”
https://www.sigma3ioc.com/post/my-mind-is-my-own-church
https://www.sigma3ioc.com/post/god-spirituality-v-politics-law-and-justice-commerce-religion-1
“Cotour: You left out the Biden administration and the left“
Robert, he DID mention the CCP Chinese . . .
It was assumed and implied.
I suspect that as both Biden and McConnel, IMO both clearly controlled assets of the CCP, fad from power there must be a recalibration of how both the CCP Chinese and the Russians are addressed regarding policy.
Tofu China: https://youtu.be/s-2DtL-Wjkc?si=NJ5IA5sfWEWoCrlx
And Russia, a “world power” who thought that they would take over Ukraine in one week is still fighting two years later and have suffered 300K casualties.
Infiltration and blackmail is their only way to success apparently?
Apparently.
And the Democrat party machine which is now fully and desperately radical leftist and the RINO’s are both attempting to make us all equal and all equally controlled through chaos and institutional incompetence.
I say no thank you.
Minor edit in third paragraph after second picture: “six more test launches this year”
Andi: Fixed. Thanks.
Galactic Patrol, here we come! I don’t suppose anyone knows an engineer named “Burgholm”…
Because this launch correctly placed its payload in its planned orbit, I consider it a success for my annual launch count
I was going to make a snarky comment, but you have a good point. Just because the ship cannot land, that doesn’t mean you cannot fill the next test ship with a bunch of Starlink satellites. It would get them up there and if the test ship doesn’t land, well, you’ve lost it anyway. Might as well fill it up for the part of the trip that works.
Supposedly the Ship made some in orbit maneuvers not normally done yet.
it might have sloshed the fuel tanks enough that the engines did not get a good fuel indicator and they decided to not fire them in order to test the heat shields with out possible consequences.
Without the slow down burn The Ship might have been going to fast for the heat tiles and they eventually failed.
Bergenholm, who was actually an Arisian.
Yes, I read Doc Smith, a lot. How did you guess?
Can’t wait to hear the corrective actions they’ll have to take to get the next license. The public must be safeguarded and free speech must be ended! Whoops, I said the quiet part out loud by mistake.
My interpretation of the video feeds from Superheavy and Starship suggest that in both cases, uncontrolled rolling caused both vehicles to crash.
With Superheavy, you can see the vehicle rolling slowly as it descended through the atmosphere. Then as the grid fins started to actuate to control the vehicle, they started over-correcting and the vehicle started to roll back and forth rapidly. I believe that it is was this rolling which may have unsettled the propellant and cause the failure of the engines to relight for the ocean landing. You can see in the graphic that three out of the thirteen engines light and then two immediately quit, leaving only one of the center engines running.
With Starship, the vehicle appeared to be in a continuous but controlled roll for it’s entire sub-orbital arc. It only seemed to lose control when it attempted to reorient for entry. When the fins started actuating, they did not seem to have any control authority to arrest the roll and indeed might have made it worse at some points as the airflow was moving in the wrong direction over the fins during parts of the entry. At two points I saw the roll almost arrested but when Starship was on it’s side, relative to the airflow, not in the intended belly flop configuration.
The fixes I would suggest would be an adjustment to Superheavy’s software to reduce it’s control inputs on the grid fins to better accounts for their seemingly slower actuation speed as compared to Falcon. For Starship I would suggest a more potent RCS system than Nitrogen thrusters so that better control of the craft can be maintained. I would also suggest that the roll should have been arrested before the craft attempted any reorientation prior to entry.
Robert – minor nitpick you wrote “As Starship started to descend it appeared its grid fins were working successfully to control its orientation.” The booster has grid fins, the ship has flaps.
Also watching HD video in real time of what looked like a CFD simulation of re-entry was mighty cool. Watching the plasma form under the vehicle and flaps as it reentered was astounding.
Great flight! Can’t wait for the next one!
A re-entry burn doesn’t slow the ship down significantly with regard to heating, unlike a Falcon 9 booster re-entry burn. I am surprised at how deep into the atmosphere the ship went while still moving >25000kph. I’d have expected it to be fluffier and lose energy higher up. That may be a consequence of the trajectory this time and the lack of stabilization in the proper re-entry attitude.
A bit disappointing that the booster was not able to do its landing burn. If SpaceX had its way would they have perfected the landing of the booster by now? I am thinking every week for the last year they could have been putting the booster into the air with the objective that it lands safely without destroying the landing pad. Or, could the super heavy booster be developed independent of Starship? Where it sends commercial, disposable 2nd stages into orbit, just like the Falcon 9 booster does.
Per SR above: Wouldn’t surprise me if they figured out how to recover Booster before they figured out how to reenter Ship. There was an awful lot of garbage coming off ship before the plasma showed, which I don’t think ought to be a Good Thing. Figure they have better data on Booster than they do Ship and can fly an expendable ship while recovering and reusing Booster for at least a little while. Given their learning curve, 6 more flights this year may be enough to figure it out. Cheers –
“… it might have sloshed the fuel tanks enough that the engines did not get a good fuel indicator …”
Fuel sloshing seems to be a recurring problem. Is that a point of failure that will be solved at some point?
And regarding the plan to refuel a Starship while it is in Earth orbit, is there any danger of all of that fuel exploding? I bet China would bankrupt SpaceX with lawsuits if a RUD caused massive damage to existing orbiting satellites.
Big tanks alowing for grater sloshing?
I would think they would have baffles, but maybe that is not enough?
I am not familiar enough, having only worried about fluid in fuel bunkers and ballast tanks.
IIRC, Elon has said that they weren’t all that worried about the booster as they had lots of Falcon 9 experience. This is the first time they actually even got to a booster landing burn. By the time they lit the engines for the landing burn the fuel and oxydizer should have been well settled so sloshing seems unlikely as a cause of the problem. Seems to me that some Raptors failed to start for the landing burn in a non symmetrical pattern and the grid fins could not handle the asymmetry.
geoffc: You are correct of course. I used grid fins generically, even though I was looking directly at the flaps. :)
Mr. Z.,
Thought you would mention that the spectacular real-time HD video of the start of Starship re-entry, was beamed to Starlink satellites.
I believe it was Ms. Tice that explained how they were going to attempt to accomplish that over the interference of the plasma.
Robert wrote: “As Starship entered the thicker part of the atmosphere however, some tiles could be seen flying away from the ship …”
Visible in that field of view were quite a few thermal protection tiles coming off the vehicle. I suspect that this is the reason for the loss of Starship.
SpaceX seems to have designed the tiles for ease of replacement (maintenance). I wonder how necessary this is. The Space Shuttle’s tiles were subject to quite a few problems, such as strikes from material falling off the External Tank and debris kicked up from the landing runway. Starship has neither condition, so their tiles may survive much better. I suspect that SpaceX could fasten their tiles more securely than they do now, even if it takes a little more time for removal. The ultimate idea is that for rapid turnaround time they will not need to do any tile maintenance at all.
_____________
Gealon wrote: “Then as the grid fins started to actuate to control the vehicle, they started over-correcting and the vehicle started to roll back and forth rapidly.”
Overcorrection was my impression, too.
I also noticed the lack of Super Heavy reentry burn. This indicates to me that the Raptor engines are built more robust than the Merlins and are better able to withstand the various forces and stresses put on them during the fall in the thicker part of the atmosphere. Avoiding the entry burn allows them to use more propellant mass in order to put more payload mass into orbit. I have forgotten the rule-of-thumb ratio, but it is something like four or five pounds saved on the booster allows for 1 pound more payload (five tons of reentry-burn propellant reduces payload by around 1 ton).
_____________
Mike Borgelt wrote: “I am surprised at how deep into the atmosphere the ship went while still moving >25000kph. I’d have expected it to be fluffier and lose energy higher up.”
The Space Shuttle tended to descend to about 200,000 feet and remain there for the majority of its deceleration. This is around 60 km, which is just below where Starship’s signal was lost (65 km).
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Steve Richter wrote: “I am thinking every week for the last year they could have been putting the booster into the air with the objective that it lands safely without destroying the landing pad.”
The rate of manufacture is closer to one every other month rather than one a week. However, had they been able to do their first test launch with Merlin Engines two years ago, as they had desired, then they would likely have discovered many of their problems a year earlier and without the government slow walking the paperwork, they likely would be a year and a half or so farther along than they are.
“Or, could the super heavy booster be developed independent of Starship? Where it sends commercial, disposable 2nd stages into orbit, just like the Falcon 9 booster does.”
I have heard this considered. My understanding is that Starship-Super Heavy is a low-expense launch vehicle even if it were to operate as an expendable vehicle. Reusability lowers costs more and increases the availability of vehicles so that the launch cadence can be even more rapid, like the Falcons.
“And regarding the plan to refuel a Starship while it is in Earth orbit, is there any danger of all of that fuel exploding? I bet China would bankrupt SpaceX with lawsuits if a RUD caused massive damage to existing orbiting satellites.”
Yes, it could explode, but keep in mind that rocket explosions are not like dynamite or fire crackers. It is more like a burst with a whole lot of combustion. Orbital debris from such an accident can be contained by doing the retanking at low altitude so that the debris reenters in a few days.
______________
Mike Borgelt wrote: “IIRC, Elon has said that they weren’t all that worried about the booster as they had lots of Falcon 9 experience. This is the first time they actually even got to a booster landing burn. By the time they lit the engines for the landing burn the fuel and oxydizer should have been well settled so sloshing seems unlikely as a cause of the problem.”
Any sloshing in the booster this time would have been caused by all the overcorrection that seemed to be happening. However, if that really is a problem, then using header tanks would reduce that problem, as we saw with the Starship landing tests three years ago.
I’ve been watching these launches with my kids. My oldest daughter now 12 has been watching these kinds of spacex videos since the first grass hopper video that landing in all the cows. We are watching history but we are finally moving past Apollo and thinking on scale that will move people to other planets.
I want my kids to remember this is how it started.
The first stage could avoid some of the fuel sloshing problems by having two smaller fuel tanks that stay full until first burn back ignition. After that small burn all the fuel in the two larger tanks should then be settled to the bottom.
Or a small solid fuel booster engine or two could do the same thing. Just enough to settle the tanks.
The second stage could do it pretty much the same.
As for in space refueling I think they would have to dock the two ships nose to nose and then spin them about their connection point to settle all the fuel to the bottom of the tanks. Then start the transfer.
If they connected side to side then they would need to have the tanks “low point” on the side of the tanks. opposite the connection point.
Or put a floating lid on top of the fuel inside each tank But this has a bunch of other problems.
I suspect that (as another commenter also noted), most of the TPS tiles were lost because the excess rolling of the Ship exposed them edge-on to the reentry hypersonic flow.
The root problem I saw was that the Ship reentered tail-first for some reason, and the torques thus created caused it to roll beyond the ability of the fins to control it!
I’ll drop this in here, very good summary, video & factoids.
Scott Manley
March 14, 2024
https://youtu.be/8htMpR7mnaM
(19:24)
“Starship ‘punches’ a hole through the atmosphere wide enough that you can send a radio signal back through…”
I wonder if SuperHeavy’s grid fins are too close together.
Shuttle used S-turns to slough off speed. Starship looks too prone to roll.
If Elon would embrace wings and scale up at bit—he could have the space freighter proposed many years ago for powersats.
“The Space Shuttle tended to descend to about 200,000 feet and remain there for the majority of its deceleration. This is around 60 km, which is just below where Starship’s signal was lost (65 km).”
IIRC the Shuttle wasn’t all that fluffy. A nearly empty Starship would be fluffier I think. Shuttle generated some lift. At less than 90 degrees AoA Starship might manage a little. I’d use it to stay as high as possible for as long as possible.
“However, had they been able to do their first test launch with Merlin Engines two years ago, as they had desired, then they would likely have discovered many of their problems a year earlier”
Was this ever a serious thing? Merlins run on kerosene not methane.
In every video sequence shown, while on orbit Ship was venting… something. And a lot of it. At re-entry Ship was tumbling out of control, as can be seen in this stabilized clip:
https://twitter.com/ophello/status/1768481359209849070?s=19
That’s not a time to have less than perfect positioning. However heroically the flaps attempted to correctly orient Ship at the moment of interface, it wasn’t enough. Perhaps the investigation will find that Ship ran out of propellant for the thrusters before then.
Epic views! The onboard ascent shots especially. Great work SpaceX team!
I wonder if the second stage could keep enough fuel so that it can slow down enough to not need the heat shields?
I am guessing that it would only need to slow down to its first/second stage separation speed. Faster than the first stage but slower than the burn speed.
Trent; I noted the venting as well and assumed it was either Ullage motors to keep the propellant settled or venting to dispose of any propellant that was boiling off. In either case, the roll originally seemed to be intentional since I didn’t observe any change in the speed and Starship seemed to be holding it’s orientation. Things didn’t get crazy until it tried to change that orientation. The roll just continued and seemed to throw the maneuvering off and it never recovered. I don’t know what the RCS jet arrangement is, but other than the venting at the rear, I didn’t see other jets firing in the rear to control Starship. I doubt that there would only be jets in the nose, so the lack of jet firing in the rear, might actually speak to an RCS failure.
Granted all of this is just armchair quarterbacking and we’ll have to wait to see what SpaceX says, but that’s my interpretation of what was on the video.
My prediction now is that it will be no less than three months before the next launch permit will be issued, placing the next test launch sometime in June.
This is the safe bet, and I won’t say you’re wrong to suggest it.
But given the progress IFT-3 made – the booster and Starship were actually disposed of where SpaceX had planned, basically – I sense that SpaceX’s mishap investigation won’t take as long as the last one. That doesn’t oblige the FAA to grant a license promptly, but they also can’t grant one until SpaceX gives them their report, either. I do not think that May is out of the question for IFT-4. Stay tuned.
Just because the ship cannot land, that doesn’t mean you cannot fill the next test ship with a bunch of Starlink satellites. It would get them up there and if the test ship doesn’t land, well, you’ve lost it anyway.
We don’t know the full assessment on how the payload door functioned on its test, but unless there was some very big hangup we do not know about, I think there is a good chance that that SpaceX might send up at least a couple Starlink (full size V2) to test out the “pez dispenser” deployment system on IFT-4. Unlikely to be a full load, but at least a couple to test it out.
Speculation on Superheavy / Starship end-of-flight issues.
Superheavy: in watching the return I noticed that rapid grid-fin oscillations began as the booster penetrated a cloud deck. I speculate the oscillations were occasioned by penetration of a windshear layer at near supersonic speed.
Windshear was expressed as a flight concern earlier in the day. Note the clouds. Convection at early dawn is unlikely, but the clouds could have been caused by the mixing of two air masses with differing flow speeds, directions, temperatures and humidity levels – causing wind shear.
In this phase of flight, the booster is relatively light with most weight in the engines at the bottom, but the majority of the hull nearly empty. Thus we have a large, empty object moving very fast, encountering turbulence!
Such oscillations could cause excessive sloshing, especially in the upper Methane tank at the light end, leading to disrupted flow in the fuel downcomer, in turn leading to engine failure.
Ship: here I am going to be even more speculative, and suggest that there is a connection to the decision to terminate in the Indian Ocean, rather than the Pacific near Hawaii. Could it be that SpaceX anticipated some stability issues, and could not satisfy the FAA that the descent path could be adequately controlled for a more-distant landing zone?
A naturally-stable aero-shape might have settled into a benign belly-first attitude, but it looked like the fins were aggressively trying to control the ship as it rotated on two axes (tumbled), but lacked the control authority.
Both of these endings may have provided sufficient data to allow design changes to be made that result in success. After all, the control systems of both booster and ship failed in flight realms that neither had ever before entered!
“I wonder if the second stage could keep enough fuel so that it can slow down enough to not need the heat shields?”
No way.
The problem with trying to figure out what went wrong is a lack of knowledge of what success would have looked like. We had minimal knowledge of the test plan and very little knowledge of how the objectives were to be accomplished. Thank you, wayne, for linking to Manley’s analysis. He notes how difficult it is for us to determine just what went wrong, and he does some speculation based upon deviation from his own expectations. I think we all do this speculation, but maybe that is part of the fun of watching the tests.
We like to think that SpaceX is a very open company, but it keeps a lot of what it knows and does close to the vest. Much of what we know is from the public access that we have to its various facilities. Unlike the heritage space companies, which bought huge tracts of land back in the 1950s and 1960s, SpaceX owns a few acres here and a few acres there, and for half a decade they did a lot of work out in the open.
The advantage for us is that we get to see development work in progress. The disadvantage is that we have to guess whether an engine was intentionally tested to destruction or if there is a real problem brewing in the next version.
_______________
Steve Richter,
You wrote: “I am thinking every week for the last year they could have been putting the booster into the air with the objective that it lands safely without destroying the landing pad.”
The ability for rapid development is catching on. Robert had an update on Stoke Space, last week ( https://behindtheblack.com/behind-the-black/points-of-information/update-on-rocket-startup-stoke-spaces-effort-to-make-completely-reusable-rocket/ ) in which the linked article quoted the Chief Executive Officer:
There are a lot of new startups, and many seem to have learned the lesson that rapid development is necessary. Getting into the space business is expensive, partly because it takes so long to develop a product — the launch vehicle, the spacecraft, or the in-space process — and partly because testing is expensive, each launch costing millions (or tens of millions) of dollars. Small satellite ccompanies can share that launch cost, but launch companies cannot.
So, had SpaceX found a way to safely land Super Heavy, they probably could have launched one or more test units often, maybe even weekly, on hop-like tests just to learn how to catch it with the “chopsticks.” Rapid development.
I’m not sure that SpaceX could do it with Super Heavy, but they already had a license to fly Starship locally (vertically) up to several miles altitude, so flying from the Starship launch pad, hovering, then landing on the landing pad could have happened several times until they were ready to hover next to the launch tower and catch Starship with the chopsticks. Proof of concept testing.
_______________
Mike Borgelt,
For a non-ablative reentry, there is a minimum altitude, as shown by the dark line on the first graph on the following page (Figure 5):
https://www.researchgate.net/figure/Earth-Re-entry-paths-as-Velocity-altitude-graphs-showing-the-influence-of-the_fig4_261316575
Please note that it is a velocity vs altitude graph. Neither time nor downrange distance is included.
If you are returning from the Moon or other “infinity” altitude, you still have to remain above that line in order to have a non-ablative reentry. Starship must remain above that line, and that almost certainly means some amount of lift for some missions. This would explain why there are heat tiles installed on the “upper” side of the nose.
Yes, using Merlin engines and RP1 was a serious thing. It did not happen because SpaceX tired of waiting for a flight license and chose to wait for the Raptors instead. The test was not for Raptor performance but for other system performances. Could they have discovered their hydraulic problem early? They almost certainly would have discovered their problem with the pad concrete. There were sixty-something corrective actions between April and November 2023, and many of them could have been corrected in 2022 instead. They may have gotten much farther along on separation and orbital flight, and may have had success on reentry and landing by now, if only they could have gotten flight licenses earlier and started with the hardware that they had at the time.
________________
pzatchok,
To expand a bit on Mike’s succinct response:
To slow down to the separation speed would require about as much propellant as was used to go from separation to orbit. Thus, to get to orbit, you would then need another stage that had the propellant to get Starship and its deceleration propellant to orbit, and that would be somewhat larger than Super Heavy, which gets Starship around 1/4 of the way to orbit. Thus, to get Starship and a larger-than-Super Heavy sized second stage to separation, a Super Duper Heavy booster would be needed.
Using atmosphere to slow down during reentry was a wise choice made early in the space age.
The Space X launch carried an extremely high payload. What was it actually carrying aboard it? Satellites? Maybe, but what else? Laser systems?
Matthew Hill: As the SpaceX announcers noted, the payload on this test flight was the data. The only physical payload I am aware of on board was the propellant transfer demo, testing the refueling technology SpaceX is developing for refueling Starship in orbit.
They also tested the ability of Starship to open and close its payload doors, but deployed nothing into spae during that operation.
Edward
“pzatchok,
To expand a bit on Mike’s succinct response:
To slow down to the separation speed would require about as much propellant as was used to go from separation to orbit. Thus, to get to orbit, you would then need another stage that had the propellant to get Starship and its deceleration propellant to orbit, and that would be somewhat larger than Super Heavy, which gets Starship around 1/4 of the way to orbit. Thus, to get Starship and a larger-than-Super Heavy sized second stage to separation, a Super Duper Heavy booster would be needed.”
I was thinking that after separation lets just say that the second stage boosts for 1 hour to get things into a higher orbit and then deploys its cargo.
Its mass is now lower by the cargo and the fuel that got it higher.
Thus it would only need the same or less fuel mass than it used to boost the second stage to its higher orbit. So a one hour burn would need only a one hour burn to slow down back to separation speed.
So yes it would need some extra fuel and would thus lower its cargo limit but with out several tons of heat shield they could add that mass back to the cargo or fuel.
Now this might only be done from orbital flights but I could see the possibility. Coming from the moon or mars it would have a chance to get more fuel from its take off point. From either the surface of the moon pr Mars or from orbit around those bodies. Its tanks could be topped off before coming back into Earths orbit.
They can not do this with the Falcon 9 because the cargo limit is so to low to allow for landing gear and the extra fuel. There would be no cost saving.
“Using atmosphere to slow down during reentry was a wise choice made early in the space age.”
It was all they had. They had no other choice. It was either let it slam into the ground or let it burn into through the atmosphere to slow down until parachutes could work..
It was all they had unless they took the leap all the way to what we have today with Space X.
And it turned out to not be perfect for an object the size of the shuttle.
pzatchok: “So yes it would need some extra fuel and would thus lower its cargo limit but with out several tons of heat shield they could add that mass back to the cargo or fuel.”
I think you underestimate the propellant requirements to get from staging to orbit. Starship carries over 1,000 tons to do this job, but the structure is around 100 tons, including engines and heat shielding.
It would need this 1,000 tons to reenter as you propose, but it would then have to accelerate that same 1000 tons to orbit, and its maximum payload capability is around 15% of that.
“It was all they had. They had no other choice.”
It is still all we have. We still have no choice. Mike Borgelt was right to say “no way” and not just say “no.” Even SpaceX doesn’t have that capability. They are doing amazing stuff, but they are still constrained by the laws of physics.
Star Trek Original Series
“I can’t change the laws of physics…”
https://youtu.be/0xD9qEdHFIE?t=12
My dream would be for Elon, Bezos and some good retired Boeing folks to build the methalox Space Freighter::
https://j363j.medium.com/the-boeing-space-freighter-a-giant-leap-for-future-space-exploration-4103542a2178
https://up-ship.com/blog/?p=6104
https://m.youtube.com/watch?v=cVYbbWAd2WA&t=39s
Had SS/SH been winged—They both might be safely on the tarmac now.