Space Stuff and Launch Info

In summary, the SpaceX Dragon launch is upcoming, and it appears to be successful. The article has a lot of good information about the upcoming mission, as well as some interesting observations about the Great Red Spot.
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9 hours and 30 minutes. Still on track for a launch.

NASA coverage will start about 4 hours before launch.
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  • #1,262
I just got back to this. So the flight was scrubbed?
  • #1,263
A valve issue. Again.
Remember June 2023? Or August 2021?

Edit: It's a valve issue on the rocket this time, not a Starliner problem.
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  • #1,266
Sorry for the dumb question, but what is helium used for in the rocket? It's an inert gas, right?
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  • #1,268
According to ChatGPT:

Helium serves several important purposes in rockets:
  1. Pressurization: Helium is commonly used to pressurize the propellant tanks in rockets. As the rocket burns fuel and the propellant tanks empty, helium is injected into the tanks to maintain the necessary pressure for propellant flow.
  2. Purging: Helium is also used to purge and inert the fuel and oxidizer lines in rockets, preventing the formation of potentially explosive mixtures of fuel and oxidizer gases.
  3. Cooling: In some rocket systems, helium is used as a coolant for various components, such as the engine nozzles, to prevent overheating during operation.
  4. Gas generators: Helium is sometimes employed in gas generators, which provide the energy needed to drive turbopumps that feed fuel and oxidizer into the rocket's combustion chamber.
Overall, helium plays a crucial role in ensuring the safe and efficient operation of rocket propulsion systems.
  • #1,269
Ah, pressurizing the propellant tanks and purging the fuel lines makes sense. Thanks guys. :smile:
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Borg said:
According to ChatGPT:
I’ve never heard of helium being used to drive turbines or cool nozzles. You’re leaving performance on the table that way, and helium isn’t a very good coolant compared to your fuel, whether it be hydrogen, methane, kerosene, or hydrazine derivatives.
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  • #1,271
Agreed, but...
We are arguing with a computer (ChatGPT), we will not be allowed to win!

"join us and live in peace, or pursue your present course and face obliteration." :eek:
(from: The Day The Earth Stood Still")

  • #1,272
No earlier than May 25 for Starliner, they are still working on the helium leak.
The ISS schedule is free until early June at least or maybe even early July, if it gets delayed beyond that then ISS scheduling could shift the launch further.

A Falcon 9 booster has flown for the 21st time, going beyond the previous limit of 20 launches.

Portugal and Spain had an extremely bright fireball. Some clips
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  • #1,273
Quarterly statistics:

In the first quarter of 2024, SpaceX launched 429 tonnes, or 87% of the global mass to orbit.
Its main competitor, ULA, launched 1.3 tonnes.
Everyone else combined launched ~65 tonnes (China 31, Russia 24, Japan 5, India 3)

Edit: Starliner is delayed, no longer targeting May 25, no new (public) launch date yet.

Edit2: Starliner is now scheduled to launch no earlier than June 1.
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Will Starliner ever get off the ground? Seven years and holding.
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gleem said:
Will Starliner ever get off the ground? Seven years and holding.
Yes, if for no other reason than to finish the contract to prove it out. After that? Probably not. Too expensive to launch it compared to Dragon.
  • #1,278
Looks like they figured out the reason for the automated Hold near the end of the weekend launch countdown, and will try again on Wednesday.

BTW, TIL that the tall towers surrounding the launch vehicle are for lightning protection. I've been wondering what they were for... :smile:



The latest attempt at an inaugural crewed launch of Boeing’s Starliner spacecraft is on track for Wednesday after a computer issue halted the countdown just moments before liftoff on Saturday.

The historic mission, called the Crew Flight Test, is set to launch at 10:52 a.m. ET from Cape Canaveral Space Force Station in Florida. The event will stream live on NASA’s website, with coverage beginning at 6:45 a.m. ET.

United Launch Alliance technicians and engineers assessed the ground support equipment over the weekend, examining three large computers housed inside a shelter at the base of the launchpad. Each computer is the same, providing triple redundancy to ensure the safe launch of crewed missions.

“Imagine a large rack that is a big computer where the functions of the computer as a controller are broken up separately into individual cards or printed wire circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a Saturday news conference. “They’re all stand-alone, but together, it’s an integrated controller.”

The cards within the computers are responsible for different key systems that must occur before a launch, such as releasing bolts at the rocket’s base so it can lift off after ignition.

During the final four minutes before launch, all three computers must communicate and agree with one another. But during Saturday’s countdown, a card on one of the computers was six seconds slower in responding than the other two computers, indicating that something was not correct and triggering an automatic hold, according to Bruno.

Over the weekend, engineers evaluated the computers, their power supply and network communications between the computers. The team isolated the issue to a single ground power supply within one of the computers, which provides power to the computer cards responsible for key countdown events — including the replenishment valves for the rocket’s upper stage, according to an update shared by NASA.

Starliner teams reported no signs of physical damage to the computer, which they removed and replaced with a spare. Meanwhile, mission specialists continue to analyze the faulty power unit to better understand what went wrong.

The other computers and their cards were also assessed, and all of them are performing normally as expected, according to the ULA team.

The Starliner mission management team reviewed the computer replacement troubleshooting steps that were taken, and they have agreed that Starliner is “go” for launch on Wednesday, according to an update from NASA.

“I really appreciate all the work by the NASA, Boeing, and ULA teams over the last week,” said Steve Stich, manager of NASA’s Commercial Crew Program, in a statement. “In particular, the ULA team worked really hard to quickly learn more about these issues, keep our NASA and Boeing teams informed, and protect for this next attempt. We will continue to take it one step at a time.”
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  • #1,279
Starliner is now NET June 5, 14:52 UTC (in 12:30). NASA coverage will start in 7 hours.

Starship is NET June 6, 12:00 UTC (in 1 day 9:40). Launch license granted
Mostly the same profile as the previous flight. No propellant transfer as that was already successful last time. No reentry burn, it's unclear why this gets skipped. The main goal is to study the reentry profile. If the ship survives reentry then it will attempt the landing flip maneuver. The booster will attempt a soft "landing" on an imaginary tower over the ocean.

Two important flights planned within 24 hours, but the two approaches couldn't be more different. Starliner will fly a crew for the first time, so everyone is extremely cautious about everything. It has been delayed multiple times and further delays are not unexpected. Meanwhile Starship flies to see what will break - it's unlikely the mission will be a full success, and that is okay.

Edit: The maiden flight of Ariane 6 is now planned for July 9.
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  • #1,280
NASA coverage has started, the astronauts have arrived at the launch tower. T-3 hours
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Good separation from the rocket, now preparing for a short burn to circularize the orbit and then more burns to get closer to the ISS orbit.
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  • #1,282
About damn time. I was beginning to worry that the joking “if it’s Boeing, it’s not going” was going to be serious.
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A little late but liftoff in three minutes.
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  • #1,284
Starship reentry video was amazing - seeing the flap gradually being burnt through (and the camera being gradually destroyed by debris), yet it survived!
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  • #1,285
Apparently both the booster and the ship could go standstill at the end of the flight, at low altitude.
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  • #1,286
Yeah, the flaps will need some more work before they can be reused. The ship still made it to a controlled splashdown.

One booster engine failed seconds after liftoff and one engine failed during the landing burn but that's well within the margins.
SpaceX confirmed that future Starships will have a lighter hot staging ring that can stay attached.

Besides the flap issue, the ship reentry looked really calm and controlled. The booster splashdown looked perfect.

SpaceX has already gotten approval to make more flights with this mission profile, assuming nothing happens that poses a risk to anyone. With an essentially flawless flight I assume this to be the case - which means the next flight can happen as soon as the hardware is ready, which might just be a month away. But SpaceX might choose to spend more time on the flaps first.
They could try to recover the booster on the next mission, but it's also possible they want to collect more data with another flight first.
  • #1,287
Starliner is about to dock with the ISS

Edit: Successful docking. They'll do some more checks before the astronauts can enter the ISS but now NASA and Boeing have a week to look into the new helium leak issues. I expect that they can return in that capsule, but in the worst case then Dragon could fly them home, too.

First time three different crewed spacecraft types are docked to the ISS.
First time two different crewed US spacecraft are in orbit at the same time.
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mfb said:
First time two different crewed US spacecraft are in orbit at the same time.
Didn't Gemini VI and Gemini VII, each carrying two US astronauts, rendezvous in orbit back in 1965?
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  • #1,289
renormalize said:
Didn't Gemini VI and Gemini VII, each carrying two US astronauts, rendezvous in orbit back in 1965?
I think he means different designs. Dragon and Starliner
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  • #1,290
Boeing Starliner’s crew is now on the space station after encountering new issues en route

Boeing’s Starliner mission has safely docked with the International Space Station and the spacecraft’s crew, NASA astronauts Butch Wilmore and Suni Williams, have arrived aboard the station after navigating new issues that cropped up overnight and Thursday en route to the orbiting laboratory.

This is the first time astronauts have arrived at the space station from a Boeing Starliner spacecraft.

Docking occurred at 1:34 p.m. ET. Steps were taken to more firmly secure the connection between Starliner and the space station’s port, and docking was completed about 20 minutes later.
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"The crew brought a much-needed replacement pump that processes urine aboard the station and turns it into drinking water."

According to Miles O'Brien, this was their "number one" priority.
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  • #1,292
External views of the Super Heavy landing burn, looks pretty similar to Falcon 9 but with a larger vehicle. A tower catch attempt on the next flight is possible, although SpaceX will need to analyze the water landing in more detail to determine if it's worth the risk.

There was an Australian airplane that flew into the Starship reentry zone, presumably booked by SpaceX to observe it - it's possible we'll get some views of that eventually. Despite the flaps melting, it splashed down only 6 km away from its target. That's more precise than most Mars landings.
  • #1,293
In post 1283 of this thread, the @Borg provided this link to the SpaceX video coverage of Starship 4 launch (for those of us without a direct connect to the Collective).

For me (and, I think for most), the main plot line for this video is focused on the reentry - something I've been waiting for for over 5 years - for both the technical challenge and as a critical Starship development milestone.
The technical challenge is to protect the reusable ship during reentry with the lowest mass shielding as possible. The development milestone I was focused on was the point at which Starship becomes destined for success - even if Elon and SpaceX. I think we have just passed that milestone. By my guesstimate, Starship's remaining development costs are low enough that if the whole thing was sold off, the new owner would find it far more tempting to finish it off than to scrap it. In short, I don't see anything short of WW3 stopping this thing.

But back to the technical challenge:

What made the reentry key for me was Musk's description of it in this January 2015 Popular Mechanics article:
On the windward side, what I want to do is have the first-ever regenerative heat shield. A double-walled stainless shell—like a stainless-steel sandwich, essentially, with two layers. You just need, essentially, two layers that are joined with stringers. You flow either fuel or water in between the sandwich layer, and then you have micro-perforations on the outside—very tiny perforations—and you essentially bleed water, or you could bleed fuel, through the micro-perforations on the outside. You wouldn’t see them unless you got up close. But you use transpiration cooling to cool the windward side of the rocket. So the whole thing will still look fully chrome, like this cocktail shaker in front of us. But one side will be double-walled and that serves a double purpose, which is to stiffen the structure of the vehicle so it does not suffer from the fate of the Atlas. You have a heat shield that serves double duty as structure.
My immediate thought was, "You gotta show me that". With Elon's reputation, you had to believe he could make it work - but still ... like a steam iron?
Of course, the stainless steel part worked out very well. For the most part, the unshielded leeward side of the ship stood up well.

So here is what I saw in the reentry video:
This first screen grab (below) is at 2:29:33 in the video. Notice that the time stamp at the top of the video is T+45:17 while the timestamp associated with the telemetry is 45:00. The best evidence of this "time warp" is during the booster landing. Clearly, the commentator reactions to the video off by a few seconds from each other and one commentators claims that the landing burn was late by 17 seconds. During the engine cutoff of the upper stage, the telemetry seemed to precede the video by just over a second.
That "pitch indicator" (small spacecraft outlines with the horizon lines) often seem to indicate something other than an actual pitch measurements. For example, see the video at T+9:11 where the icon does a somersault. This will be important to note when attempting to make sense of the splash down segment.
And one final telemetry quirk: those six thrust indicators will not be functioning from this point on. So don't expect anything from them during splashdown.
I've also moved the YouTube progress bar down and out of the image area.

The speed is over Mach 25 but the altitude is only 107 KM (half its apogee) - that plasma from reentry is just starting to show as a faint pink zone below the belly beneath flap. This is the "flapcam" showing the view of the aft port-side flap form the forward port-side flap. Apparently (but not surprisingly), this camera did not survive reentry.

At T+46:00 (image below) we are faster and lower. The plasma is a lot brighter - but a lot of that is because we have crossed into night and the video system is making brightness adjustments.

This next screenshot was take 6 minutes later at T+52:00, shortly after peak heating. The altitude is 68Km, which it has been for over a minute and which will remain for over another minute. The speed is about Mach 22.

There is a light gray zone above the flap showing some out-gassing. The engine is being chilled, so the out-gassing may be related to that. Also, there have been occasional "sparks" in the wind stream from belly material. There is none showing in this frame, but there will be lots more to come.

Three minutes later (image below) at T+55, we are at Mach 19.5.

Look at the unprotected steel just forward of that flap we are watching. Material from the tiles seems to be coating that metal. The unprotected surfaces seem to become more involved with the destructive wind stream as altitude and speed drop. This is the last screen shot from this camera. It lasted for more than two more minutes - during which time it showed controlled flap movement.

At T+57:15 the trouble starts.
This is another camera, another fin, the other side of the ship. The camera is mounted on the top side (protected half) of the ship on the starboard side. It is looking forward and down at the back edge and unprotected side of the starboard forward flap.
We are down to 57Km and Mach 15.7. those white streaks are intense sparks coming out of the aft underside junction of that flap with the side of the ship. But in addition to the bright white sparks, we are seeing some heat effects of the unprotected flap surface. It is just starting to redden.

The next frame is only 15 seconds later, 1Km lower, and 500 KPH slower. But something abrupt just happened. The bottom edge of the flap, where it meets the ship body, has moved away from the body by an inch or so, tile material was lost, and unprotected steel appears to be in direct contact with the wind stream.

Below: 45 seconds later, Mach 13.9, 56 Km high. The flap steel has been heating up and flaking off continuously. Its trailing edge is now well-separated from the ship.
But notice something else: There are two black dots in the image - and at this point I need to describe something about the camera. The camera along with its lens are behind a window. As we will see, the camera lens will remain survive. All of the effects that are seen from this point on are with the window - not the lens.
So those black dots are material that has separated from the craft and landed on the window.

At T+59:06, the window is so coated with material that the view is best discerned by changes in glows, and at that point it starts cracking. This is where the nail-biting starts. The image is almost useless. Last we saw, the craft was doomed. But the telemetry suggests that things are holding together and the Mach number is down to a slow-searing 12.

At T+1:00:30 we see some glimmers of something (hope?) through the broken window (image below).
We are just under Mach 9, still apparently under control, and a pinkish splotch in the middle of the image tells us that the flap has not yet separated. Those light gray areas are cracks in the window where sparks (from the "flap") can still be seen flying by. So how long will things kinda hold together?

A minute later, we're dropping like a rock but with pitch still stable, the window cracks are bigger, we're just over Mach 6, the Starlink connection is mostly holding, and there is definitely still something there to call a flap.
NASA has noted that the temperatures are coming down fast and the ship is within seconds of maximum aerodynamic pressure.

At T+1:01:37, the video is lost "Awaiting acquisition of signal".
At T+1:02:24 we get the video back - but it's hard to interpret. We're at Mach 3.5 at 33Km over the Indian Ocean at night. But the window is gone. The only sources of light look like remnant cinders.

There are pitch maneuvers and then, at T+1:03:05 some light flashes that suggest to me that they may have been using jets to augment the flap control. At T+1:03:20, telemetry shows a drastic pitch down orientation. Previous simulations had shown some pitch down before the main rockets kicked in, but this seemed extreme. It is also possible that that "pitch icon" was just showing something other than a pitch measurement.

We can also make out the flap from time to time - and it appears to be under control.

Next, at T+1:03:58 we see the trailing edge of that forward flap we've been watching lit up by the initial ignition of the main rockets. The slight down pitch is consistent with simulated renditions. The speed is a very tame 722KPH and altitude is 14Km.

Would you believe that I am only allowed to attach 10 photos to this post??
Guess you'll have to watch the next 2.5 minute of the video - to mission end.

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  • #1,294
The RCS is used for slow maneuvering in space, it's useless in the atmosphere. From the time the flaps gain control in the upper atmosphere until the start of the landing burn the ship is purely controlled via its flaps. At 14 km something glowing hot zips past the camera. There is more later.

The first engine use happens at 1:05:39, the ignition of the final landing burn.
.Scott said:
My immediate thought was, "You gotta show me that". With Elon's reputation, you had to believe he could make it work - but still ... like a steam iron?
Transpiration cooling was abandoned - probably too complicated to get the liquid everywhere.

Starship is a useful rocket even without any reuse, and a very competitive rocket with booster reuse. Falcon 9 shows that landing and reusing boosters works, it's going to work for Starship as well.
  • #1,295
Once they work out the bugs, it’s absolutely going to be a game changer. I suspect that all the other big players are waiting to see how SpaceX does it, and then they’ll either snap up some of the burned-out engineers that SpaceX uses up almost as fast as Superheavy uses up propellant, or they’ll just use espionage, to get the inside scoop on all the hard lessons. Then they’ll make their own take on it.

ULA is going to have to re-evaluate the entire Vulcan partial reuse system very quickly if they want to be competitive for even DoD contracts.

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