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Bob:
I think you may be right. That sure looked like a fire to me.
I noticed the white "vapor" of some kind being vented from the engine compartment, in the thin air several seconds ahead of the first sign of the fire. It's not possible to say whether that is an unintended propellant leak or an intended flowing of cold propellant to pre-cool the engines to operating temperature.
Whatever it was, the gases in the engine bay did seem to catch fire as the booster descended into thicker air. There is a pressure below which fuel-air ignition is not possible. That fire started nearer leeward in the bay, but quickly extended all across it, around the center 13 engines. I did not see any fire around the outside ring of 20 engines, and I do not understand that at all, not yet, anyway.
I am glad there was no apparent oxygen leak into this fire. That would have precipitated an immediate (and fatally destructive) explosion.
GW
Last edited by GW Johnson (2024-10-30 10:41:29)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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For GW: I use the $14/month no ads service and am very sorry that you experienced the advertising avalance you described!
Rodger
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Back to the business at hand: the date being bandied about for IFT6 is still 11 November. Nothing has been stated regarding mission profile, however.
Last edited by Oldfart1939 (2024-10-30 12:22:36)
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I suspect it (the mission profile) will be similar to flight 5, except that they may attempt to circularize outside the atmosphere, to test the in-space restart capability. If they do, then the Starship might proceed around multiple orbits, instead of a fractional orbit, then do a second restart to do the deorbit burn. They might even attempt more simulated propellant transfer by venting pumped liquid to space.
They might bring this one down in the Pacific off California, or in the Gulf off of Florida. I doubt they would attempt a drone ship landing, because this thing is way too big for the drone ships they have. I doubt they would try to land on a pad in Florida, because overflying inhabited land to get there is a major launch license change. But I REALLY doubt they would attempt a catch landing at Boca Chica, for 2 reasons: (1) bringing it down over the US land mass is a major change to the launch license, and (2) they won't have had time to clear the tower of the attempted booster recovery. They only have the one tower so far.
Just my opinions, I have no facts.
GW
Last edited by GW Johnson (2024-10-30 14:40:48)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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For Gw Johnson...
One of the Videos about Startship that members have linked recently included s speculation that an attempt to fly two Starships at once is in the queue for early 2011. That one would test propellant transfer. A second Chopsticks tower is needed.
(th)
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I'd first concern myself with fixing or preventing the nozzle bell damage (thankfully this wasn't catastrophic- a testament to the strength of the components), engine bay fires if such a thing actually happened (because that is deadly serious), grid fin damage (these were definitely more "well done" than usual), and any heat shield damage near the fins on Starship (the damage at the hinge line has been catastrophic or near-catastrophic during all flights). None of that is acceptable if rapid and complete reusability is one of their program goals. After those basic safety of flight issues have been resolved, there's plenty of time to run through different flight profiles to expand the flight envelope, attempt propellant transfers, as well as any other missions that strike their fancy.
SpaceX needs at least one completely clean test flight where nothing gets damaged or destroyed. Their achievement is truly historic, just to be clear, but barely surviving the flight is not good enough.
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I suspect the next IFT will essentially be a near repeat of the last one. The FAA license approved both IFT 5 and IFT 6, but if there are significant changes, they will necessitate a new one.
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This is a follow up on #1955
Title: SpaceX wants to test refueling Starships in space early next year
https://techcrunch.com/2024/11/01/space … next-year/
SpaceX will attempt to transfer propellant from one orbiting Starship to another as early as next March, a technical milestone that will pave the way for an uncrewed landing demonstration of a Starship on the moon, a NASA official said this week.
Much has been made of Starship’s potential to transform the commercial space industry, but NASA is also hanging its hopes that the vehicle will return humans to the moon under the Artemis program. The space agency awarded the company a $4.05 billion contract for two human-rated Starship vehicles, with the upper stage (also called Starship) landing astronauts on the surface of the moon for the first time since the Apollo era. The crewed landing is currently scheduled for September 2026.
Kent Chojnacki, deputy manager of NASA’s Human Landing System (HLS) program, provided more detail on exactly how the agency is working with the space company as it looks toward that critical mission in an interview with Spaceflight Now. It will come as no surprise that NASA is paying close attention to Starship’s test campaign, which has notched five launches so far.
SpaceX made history during the most recent test on October 13 when it caught the Super Heavy rocket booster mid-air using “chopsticks” attached to the launch tower for the first time.
“We learn a lot each time [a launch] happens,” Chojnacki said.
Chojnacki’s work history includes numerous roles in the Space Launch System (SLS) program, which oversees the development of a massive rocket of the same name that is being built by a handful of traditional aerospace primes. The first SLS rocket launched the Artemis I mission in December 2023, and future rockets will launch the subsequent missions under the Artemis program. No part of the rocket is reusable, however, so NASA is spending upwards of $2 billion on each launch vehicle.
The first contracts for the SLS program were awarded over a decade ago under what’s known as a “cost-plus” model, which means that NASA pays a base amount plus expenses. (This type of contract has been stringently criticized for incentivizing long development timelines and high expenses.) In contrast, HLS contracts are “fixed-price” — so SpaceX receives a one-time $2.99 billion payment provided it meets certain milestones.
Chojnacki said NASA has taken very different approaches to the HLS versus SLS program, even beyond the contracting model.
“SLS was a very traditional NASA program. NASA laid out a very strict set of requirements and dictated propellant inventory, dictated all the things to the various elements. They flowed down. They were cost-plus programs where the aerospace companies would respond, and we would work in a very traditional manner,” he said. “Moving to HLS, we’re doing a lot of moving parts at one time. On SpaceX’s contract right now, for their initial landing, there are 27 system requirements. Twenty-seven, and we kept it as loose as possible.”
Under SpaceX’s contract, they must meet mandatory design reviews, but SpaceX can also propose additional milestones for payment. One requirement that SpaceX requested is the ship-to-ship propellant transfer demonstration. Those tests are set to begin around March 2025, with testing concluding in the summer, Chojnacki said.
“That would be the first time that’s demonstrated on this scale, so that is a big building block. And once you’ve done that, you’ve really cracked open the opportunity to move massive amounts of payload and cargo outside of the Earth’s sphere. If you can have a Starship with propellant aggregation, that’s going to be the next step to doing an uncrewed demonstration.”
In addition to the testing, the next major review of Starship will be the Critical Design Review (CDR) in Summer 2025, which is when NASA certifies that the company met all 27 of those system requirements. Chojnacki said NASA astronauts also meet with SpaceX once a month to provide input on Starship’s interior. The company is building mockups of the crew cabin, including the sleeping quarters and laboratory, at Boca Chica. NASA anticipates getting a design update this month before looking at it during the CDR next year.
That isn’t the only place where NASA has offered its input: It also offered input on some aspects of the rocket design, like the vehicle’s cryogenic components, as well as conducting some testing on the thermal tiles that help keep the cryogenic fuels cold.
If all goes to plan, SpaceX will land astronauts on the moon in September 2026.
“That is definitively the date we’re working towards. We don’t have any known road blocks. We do have some first-time things that have to be demonstrated, and we have a plan in place to go demonstrate those.
(th)
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According to Musk, they are targeting Nov 18 for flight 6. We will see if the team is really ready. He pushes too hard, has a history of that. It shows in "Musk time" being factor 2 to 3 shorter than reality. The flight profile has to be similar to flight 5, or it would require a new launch license from FAA. Watch for (1) no more flap hinge line burn-throughs, and (2) touching down on the ocean without exploding. Actually, I rather doubt that 2 is possible. It's bound to bust a tank, toppling over into the sea. If oxygen hits a fuel-air fire, the fire always explodes.
GW
Last edited by GW Johnson (2024-11-07 09:50:50)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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What I have been reading is that they want to do the engine relight in sub-orbit, and they want to challenge the heat shield.
I read that they are going to try a steeper descent to challenge the flaps. I suppose that it may also be possible that with a steeper descent, more heat can be shed from the process as radiation rather than as heat sinking into the flaps. (That is my feeble theory). But of course they may want to challenge the flaps now, as later on they will want to try to recover ships. Destructive testing, I suppose.
The other things I observe from "The Blab", is that they are going to remove some tiles from the sides, apparently to see how well the ablative under protection works, and they also need to find a way to have landing projections for the catch tower. Currently the heat shield, does not allow for that.
Just what Blab I have seen.
Ending Pending
Last edited by Void (2024-11-08 07:41:29)
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The 18 November date has been confirmed by the issuance of a NOTAM by the FAA for that date (NOtices To AirMen).
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Following up on the post by OF1939 #1961...
Here is a link to a discussion of plans for the flight on November 18th.
There is quite a bit of detail included.
https://starship-spacex.fandom.com/wiki … ght_Test_6
The in-space engine restart is included, along with removal of tiles to make way for side catch supports.
Those supports will have to survive re-entry heating.
(th)
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I’d like to get some feedback on these estimates I made after I heard Robert Zubrin say Elon told him the Starship, i.e., the upper stage only, could be made for ~$10 million production cost:
https://twitter.com/spacewatchgl/status … 6932841756
I was surprised that Elon estimates a Starship only cost of ~$10 million. At a ~$10 million Starship cost, SpaceX should investigate it as 1st stage of a smaller system, with a mini-Starship as the 2nd stage at perhaps only ~$2 million additional cost, due to its proportionally smaller size. Get ~100 ton to LEO Saturn V-class launcher at only ~$12 million cost(!)
As the first stage now, Starship loses only a proportionally small payload by reusing if you land it down range. Then close to a 100 ton partially reusable launcher for only ~$3 million(!) Say, payload reduced to 80 tons with partial reusability. Then price per kilo only $3 million/80,000kg = $37.5 per kilo(!)
Bob Clark
Old Space rule of acquisition (with a nod to Star Trek - the Next Generation):
“Anything worth doing is worth doing for a billion dollars.”
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It's kind of hard to evaluate your idea, because I have no clue as to the mass and weight statement of the "mini-Starship" upper stage. It's also a bit hard to know what the real thrust of a Raptor-2 or Raptor-3 engine is, and which configuration those data are for (sea level or vacuum).
Starship as it has been flying is somewhere in the vicinity of 120 metric tons inert, and 1200 metric tons propellant in the tanks. It has been flying at zero payload, and not with all the features of an operational LEO freighter. We will ignore those very fundamental difficulties.
I will just do a wild guess of 200 tons for an upper stage "mini-Starship", which might carry 10-30 tons of deliverable payload. Maybe. Maybe not.
Weight statement for launch configuration: payload = loaded "mini-Starship" = 200 m.tons, + 120 m.tons 1st stage inert + 1200 tons 1st stage propellant = 1520 m.tons ignition mass.
Kinematic requirement: T/W ~ 1.5 at liftoff in order not to waste propellants accelerating too slowly.
Take a wild guess as to the max thrust per engine of a sea level Raptor-3: call it 250 m.tons-force. Raptor-2 is not that high. But we are looking to the future here.
Starship as we know it is 9 m diameter. The three center engines are sea level, and they gimbal for thrust vectoring. The outer 3 are vacuum with much larger bells, but are fixed in mounting. Take a wild guess that we could replace these three vacuum Raptors with 6 sea level Raptors, also fixed in mounting. That is a total of 9 sea level engines, for a total of about 2250 m.tons-force at liftoff.
The thrust/weight ratio at liftoff is then about 2250/1520 ~ 1.5, which is adequate to fly efficiently. But, the 200 ton upper stage mass limits your deliverable payload to a low number, likely down near 10-30 m.tons! Raising the upper stage mass lowers the launch thrust/weight. That means the gravity loss dV is going to be much higher!
I'm quite unsure this is a good approach at 9 m diameter. The requirements on the first stage are quite different from those imposed on the second stage. You have to look at thrust/weight as well as the rocket equation. If you fail to look at thrust/weight, you get bad answers from the rocket equation.
GW
Last edited by GW Johnson (2024-11-14 15:41:54)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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I think that SSTO I proposed would make a fantastic upper stage for the Super Heavy booster. It generates lift, so it has cross-range and can land on a runway. The pressurized passenger compartment could be used to return ZBLAN fiber optic cable from orbit, back to Earth, with a lower probability of loss than a vertically landed upper stage. The fiber optic cable cargo would be much easier to offload than it would be from Starship, and the crew could oversee the loading and unloading of the cargo. The upper stage could then be flown back to the launch pad using a conventional jet engine, for which there's plenty of mass margin since it doesn't need to achieve orbit all on its own. The booster provides enough of a Delta-V reduction that the vehicle could achieve high orbit to drop off passengers, come back down to a lower orbital altitude to pick up ZBLAN from the manufacturing plant, and then return to Earth, and to choose where to land to offload the cargo. It could go to Silicon Valley, Japan, South Korea, or anywhere else that a paying customer wants the latest and greatest fiber optics tech for their networks, which would probably be anywhere with a runway capable of landing an airliner.
Passengers could go up to an awaiting interplanetary transport for the lucky few who get selected to venture out to our colonies, the vehicle reduces its orbital altitude to stop by an orbital manufacturing facility to pick up fiber optics or photonics "chips" or similarly valuable products, and then the high value cargo and any returning passengers reenter and fly to an airport of convenience (for delivery of the cargo) here on Earth. The passengers then fly back to the states or wherever they're originally from, aboard a commercial airliner. There are revenue generating payloads going both ways, so the ticket price to go to another planet could be reduced since some of the generated revenue comes from the passengers and the rest comes from high-cost / high-demand electronics and telecommunications products that we'd very much like to use to replace existing Copper or lesser quality fiber optics here on Earth, but unfortunately the ZBLAN crystals grown on Earth look like crap, whereas ones grown in orbit look flawless.
This would be the first practical application of space, used to simultaneously unlock interplanetary transport and orbital manufacturing of next generation computers and communications equipment. The photonics-based computing and sensor tech would dramatically reduce the energy consumption associated with data center computing and AI, which is now eating more energy than the entire global air travel industry. Low cost fully reusable rockets are akin to a "cheat code" to level-up our tech and travel capabilities. There's an implicit defense application for Space Force as well. If we can use some of the interplanetary transport tech to go after the metals in the main belt, then we get functionally unlimited Platinum group metal catalysts for advanced energy tech, CO2 removal, and various other technological "goodies". Beyond that, we need to find new sources of Copper and Silver, or this idea of electrifying everything will remain a dream forever.
Our newly formed "Department of Government Efficiency" should appreciate the "How many different birds can we kill with the same stone?" aspect of this as well. We have lots of people with degrees, and we just imported millions of people with hand labor skills but no degrees. Unfortunately for both groups, there are few jobs worth doing because they don't ultimately take us anywhere new. Solving these engineering-based problems, none of which are beyond our technical capabilities so they need not devolve into endless pointless science experiments, would be well worth the time and labor devoted to it.
I think WWIII is already in-progress, even if it remains undeclared, but this "unlock space" project would become the "silver lining" following the hell on Earth that we're about to be subjected to. Our children can look forward to this on the other side of the war- something which puts those of us who remain onto a project that is broadly beneficial to humanity, and provides a huge surge in demand for people, ideas, materials, and technologies. The Greatest Generation had the opportunity to "remake the world" following WWII. Our children will get the same opportunity. Everything involving humanity operates over cycles. Along the way, we somehow manage to progress a bit.
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The conclusion you could get a Saturn V-class launcher, i.e., 100 ton payload to LEO, using the Starship as a 1st stage and a “mini-Starship” as an upper stage is based on the estimate Elon once made for an expendable Starship dry mass:
Elon Musk @ElonMusk
Probably no fairing either & just 3 Raptor Vacuum engines. Mass ratio of ~30 (1200 tons full, 40 tons empty) with Isp of 380. Then drop a few dozen modified Starlink satellites from empty engine bays with ~1600 Isp, MR 2. Spread out, see what’s there. Not impossible.
https://x.com/elonmusk/status/1111798912141017089?s=61
But that is for an upper stage use where it did not have enough engines for liftoff from ground. Assume for 1st stage use it needs 9 engines. Increase the dry mass now to 50 tons for the greater engine mass.
For the mini-Starship, an upper stage commonly is 1/3rd to 1/4th the size of the lower stage, so call it 300 tons propellant mass. As an upper stage it doesn’t need high engine thrust so assume same mass ratio of ~30 to 1 as for Elon’s expendable Starship, giving it a dry mass of 10 tons.
Take Starship exhaust velocity as 3,500 m/s and the upper stage’s vacuum exhaust velocity as 3,700 m/s. Then we could get ~100 tons to LEO:
3,500Ln(1 + 1,200/(50 + 310 + 100)) + 3,700Ln(1 + 300/(10 + 100)) = 9,360 m/s.
Bob Clark
Last edited by RGClark (2024-11-15 10:49:36)
Old Space rule of acquisition (with a nod to Star Trek - the Next Generation):
“Anything worth doing is worth doing for a billion dollars.”
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Musk predicts 400 Starship launches during Trump's second term.
https://www.zerohedge.com/technology/ah … -trump-era
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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For those who have not yet had time to read the article that Calliban linked in #1967, I think the read is worth the time...
From the closing section:
Post
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Elon Musk@elonmusk
The first Starships to Mars will launch in 2 years when the next Earth-Mars transfer window opens.These will be uncrewed to test the reliability of landing intact on Mars. If those landings go well, then the first crewed flights to Mars will be in 4 years.
Flight rate will grow exponentially from there, with the goal of building a self-sustaining city in about 20 years. Being multiplanetary will vastly increase the probable lifespan of consciousness, as we will no longer have all our eggs, literally and metabolically, on one planet.
Quote
Elon Musk@elonmusk
·
(th)
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The launch seemed to go well this evening (Tuesday 2024/11/19) but the Super Heavy sat down gently in the Gulf instead of attempting a return to the tower.
It will be interesting to find out what happened to lead to the no-landing decision.
Update later ... I tuned in just as the Starship "landed" ... the keel over seemed stately to me, and the ship was floating high in the water after the maneuver. It is probably not surprising that fires were burning in the vessel after engine shutdown. There would have been some methane left over, and there were plenty of hot components to provide ignition.
SpaceX cut away from the scene, so it is a mystery what happened.
(th)
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I watched SpaceX's video of the mission, of course looking past the long times where nothing was happening. Launch looked good, hot staging looked good. The booster diverted to a water landing for no reasons I could understand watching their video.
The upper stage boosted itself onto the barely-suborbital trajectory just fine. The engine relight was about a 1 sec burn just before entry manifested itself. Entry went well, except for another hinge-line burn-through averted by the end of entry hypersonics, at the leading edge of one of the forward flaps, which forward-flap hinge line is where the other burn-through problems have occurred, except that they were at the aft end of that hinge line.
Booster recovery was aborted in favor of a splashdown, for no reasons given in the video.
The second-stage spacecraft entry and belly-flop looked fine, plus the flip to a thrusted water landing. This time, there seemed to be no explosion when the vehicle tumped over. However I saw some sort of shape change and some fires, after it did tump over. Looks to me like a methane tank broke open and started a methane-air fire. I saw no explosion from breaking open an oxygen tank, though.
GW
GW Johnson
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"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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For GW Johnson re #1970 and Booster water landing...
I saw some chatter to the effect that President Elect Trump was present for the launch.
The decision to land in water ** may ** (speculation) have been to avoid any risk whatsoever.
In light of the greater importance of the Starship tests, my guess is the chopsticks landing was of no importance in comparison.
(th)
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The reason for water landing given by several commenters was damage to the launch tower radio antenna, which was seen to be clearly bent in post-flight photos. This is speculation on their parts, but the actual damage was visible.
Last edited by Oldfart1939 (2024-11-19 22:27:51)
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Here's a link to the SpaceX notes stating the tower was definitely the issue, as the tower initiated the landing abort into the ocean.
https://www.youtube.com/watch?v=W2R1aFSkHVI&t=13s
Last edited by Oldfart1939 (Yesterday 11:57:24)
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Another link to one of the more reliable and realistic reporters on the IFT6!
Marcus House, Scott Manley, and Felix are all great, along with Tim Dodd.
Here's a link to Marcus House.
https://www.youtube.com/watch?v=Mw0jxOE … WL&index=1
Last edited by Oldfart1939 (Yesterday 22:31:21)
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