SpaceX Starship development: fifth flight, captures booster

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The engine section is pretty heavy and propellant for an ascent will lower the center of mass more. Here is an analysis.

 

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SpaceX is preparing for the WDR. It's mimicking the launch sequence but stopping just before engine ignition. It is one of the two main tests that are left to do before a launch, with the other being a static fire of all engines together.

NASASpaceflight coverage:

 

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WDR completed. The video is showing how it will look like for a launch, with ice all around the booster and covering the tank section of the upper stage on the side without heat shield. The ice-free part in the middle is the interstage (upper part of the booster) and the engine section of the ship, the ice-free part on the top is the payload section.

 

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Destacked to prepare the static fire test
The next time the ship will be on the booster it's in preparation for launch.

In other news:

SpaceX's Sarah Walker says the company is making "good progress" toward having Pad 40 at Cape Canaveral SFS ready to support launches of Dragon cargo missions to the International Space Station in the fall, then will add in crew launch capability later.

While this sounds like a Dragon announcement, it's really about Starship.
SpaceX prepares a Starship launch pad at site 39A in Florida, the same area that also handles Dragon launches. An exploding Starship could damage both pads and interrupt launches to the ISS. NASA really wants to avoid that, especially with the current situation with Russia and Starliner still not being certified.
To avoid that risk, SpaceX prepares its other launch site in Florida to handle Dragon launches if needed. That means they likely aim at initial Florida launches of Starship for late 2023 or early 2024 or so.

 

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SpaceX says it hopes to fire all engines (33) on the starship booster tomorrow.

 

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31 engines, good enough for an orbital launch. One engine was stopped before ignition by the operators, one shut down automatically. Ship is still standing, no obvious damage to the launch pad either. For the bottom of the launch mount this test was worse than the actual launch because there the rocket will move away from it.

Likely ~70 MN, far more thrust than any other rocket. Saturn V had just 33 MN, SLS has 39 MN, N1 had 45 MN.

SpaceX and the FAA will need to go through the data, but assuming everything looks fine Starship passed its last major test before an orbital launch.

 

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Update: The engines were only fired at ~50% thrust. Still enough to beat Saturn V and also a new record in terms of engines fired simultaneously (N1 had 30), but not a new thrust record.

 

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This is 50%:

 

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"From what I hear, everything is on track for a March launch attempt as far as the FAA is concerned."
Starship SN24 is still being prepared for the first orbital launch attempt. It has the full reentry and landing hardware (heat shield, flaps and so on).

SN25 is similar to SN24, it could repeat its flight profile if SN24 is not successful.
SN26 doesn't have a heat shield or aerodynamic surfaces, it is expected to be an in-orbit propellant transfer demo (within the spacecraft) and maybe a depot prototype - critical elements of the Artemis program. It could be the second or third flight.
SN27 has a Starlink satellite dispenser, it could become the first flight to deploy satellites.

 

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SN27 has a Starlink satellite dispenser, it could become the first flight to deploy satellites.

In the latest Physics Today issue there is an article discussing the role of SpaceX in placing in orbit some of NASA's large future space observatories much quicker than originally thought, including the Lynx X-Ray observatory, the Origins Space Telescope, and the LUVOR observatory.

If the Starship program can reach its payload goals these instruments might be in use decades before it was initially thought it would be possible.

 

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SLS has a similar fairing size and it can deliver all these telescope projects to their target orbit, too. It's just far more expensive and means another 1-2 years of delay for Artemis for each launch. Starship could be used for future modular telescopes with a far larger total mass.

 

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A launch license is now expected to come within the next two weeks.
A launch date could be announced once that license is issued, although Starship is very unlikely to launch on the first announced date (like every new rocket).

The booster is on the launch mount again.

 

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Ship 24 is at the launch site again.

Here is a great animation how the flight could look like (although some of the elements in it won't happen):



Edit: First set of notices to mariners, declaring potential risk areas for a flight between April 6 and April 12. It's unlikely that the launch will happen in these days, but SpaceX wants to keep the option. We'll likely get more of these with days after April 12 soon.

 

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SpaceX has informed NASA that they aim for a launch on April 10. While it is very likely that we'll see delays, and the FAA approval is still outstanding, it is still the first specific target date.
It's the "primary date" in the FAA plan, too (with April 11 and 12 as backup dates).

Edit: The ship has been stacked on the booster again.

Edit: Not April 10, unsurprisingly, now not earlier than April 17.

 

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Launch license has been issued

SpaceX confirms Monday April 17 for its first launch attempt
New rockets rarely launch on their first scheduled attempt, but a launch next week is likely now. "Excitement guaranteed", as SpaceX puts it - when it takes off then we either see at least some success or a big explosion.

 

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Something fell down the launch tower but it doesn't seem to be critical, SpaceX is still aiming at a Monday launch (in under 24 hours!).

SpaceX livestream will be here
Others:
Everyday Astronaut
NASASpaceflight

 

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T-3:30:00

NASASpaceflight stream is live.
There are traffic jams on roads towards viewing sites, even though it's 4:30 am local time.

Flight readiness poll will happen at T-2:00:00.

Edit: The propellant storage has started to get active in preparation for propellant loading.

Edit: No sign of propellant loading yet (as of 6:37 local time), looks like they won't aim at an 8:00 launch.
Edit 6:41: 8:20 via SpaceX's twitter account, so it was just a short hold and propellant loading should start soon.
Edit 6:43: Propellant load started

7:25: Ice build-up on booster and ship indicates propellant loading is going well. Under an hour to go. SpaceX coverage should start in 10 minutes.

 

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T-35 minutes

SpaceX livestream is up

 

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SpaceX is also providing a link with narration.
T-00:12:00

 

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Scrub. They will convert it to a wet dress rehearsal, finishing propellant load but there will be no ignition.

 

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First stage pressurization issue will nix a launch for today.
But they are continuing for reheasal.
Countdown clock will stop at T-00:03:00.

 

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Minimum of 48 hours to recycle.
4/19... or 4/20?

1 million watching on the SpaceX channel, 220,000 at NSF, 80,000 at Everyday Astronaut. Probably more at the time they announced the scrub but I didn't check.

 

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SpaceX is now aiming at a launch on April 20 (internet is full of 4/20 memes), giving them three days to fix the freezing valve and to replenish the stored propellant. Most of it is recycled, of course, but the operation isn't loss-free.

 

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The FAA has Temporary Flight Restrictions posted for Starbase (Brownsville, TX) for 4/20 and 4/21.

 

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Still aiming for an April 20 launch.

The FAA has released a 120 page document discussing environmental impact findings for this flight and the next two. If you ever wanted to know the size of the area around the Starship impact where a Hawaiian Monk Seal could get temporary hearing loss and how many of them we expect closer than that on average: You'll find that in the document (41.37 km² and 0.001241 animals, page 14). Even if we add up all the animals in the list then we still expect not a single temporary hearing loss as most likely outcome, but it's great that millions have been spent determining all these numbers, which also included giving some of these animals hearing loss in the lab to find the pressure thresholds used as inputs.

We can learn more about the flight plan as a side effect of all these calculations: The ship will hit the water at terminal velocity, no chance of a landing burn. The impact is expected to mix methane and oxygen, leading to an explosion with a yield of a bit over 1 tonne of TNT. The booster will do a landing burn and is expected to survive impact, it should sink after water enters through open valves. If not they might use it as military target - shoot it until it sinks.

SpaceX plans a second and third flight with a similar flight profile, but the upper stages will not have a heat shield so they won't survive re-entry. The nominal booster landing is again in the ocean, but with some option to attempt a chopstick capture on the launch pad.
It's likely SpaceX will cancel the remaining missions if they don't think they can improve on them, e.g. if they reach orbit with the first or second flight and don't think they are ready for booster recovery yet. The hardware for the first three flights is at least half a year old, what they are building now (nominally: for a fourth flight) must have hundreds of improvements.

 

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Currently, the FA has TFRs registered for Starbase for Thursday (tomorrow) through Tuesday the 25th. That include Saturday and Sunday.

 

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~90 minutes until the launch window opens. Fuel loading of the booster has started.

SpaceX stream
NSF
EDA

 

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Looking good today. Fueling nearly complete!

 

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We are farther than on Monday, so the valve issue has been solved.
Last 4 minutes.

Possible hold up to 15 minutes at T-40s, this is different from Falcon 9 which basically has to fly or do a larger recycle.

 

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Hold at -35 seconds. Might go back to -40 seconds or earlier.

 

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SpaceX Starship Launch at 8:33am CDT (local time) - cleared the pad and still going.

 

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LIFTOFF

 

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Five engines appear to be out.
Now six Stage 1 engines are out.

 

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6 engines now. Yeah, there were some smaller explosions. We'll see if that is enough thrust to reach orbit.

 

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That trajectory looks really wrong