SpaceX completes fueling test, setting stage for first launch of Starship V3

SpaceX cleared an important milestone Monday on the road to launching a new version of Starship.

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[Thomnmi]

Just for comparison, the Saturn 5 booster generated 7.5 million pounds of thrust and the old Soviet N1 Rocket was about 10.2 million pounds.

 

[Lurins]

It's about time.

 

[Cloudgazer]

Compensating for something?

The tyranny of the rocket equation?

 

[JohnCarter17]

Brutal signal to noise ratio here.

 

[Drunkahedron]

For example, in Version 3, the internal transfer tube that channels methane fuel from the top of the booster to the engine compartment is about the same size as the first stage of SpaceX’s workhorse Falcon 9 rocket, which is roughly 12 feet (3.7 meters) in diameter.

This seems unlikely. This 2024 render from Chameleon Circuit shows an oxygen landing tank (wrapped around the base of the methane transfer tube) which was roughly that large, but the transfer tube was much smaller.

Perhaps for V3, the methane sump and manifold is 3.7m wide, but if the transfer tube is that wide, it's no longer just a transfer tube.

 

[wagnerrp]

Perhaps for V3, the methane sump and manifold is 3.7m wide, but if the transfer tube is that wide, it's no longer just a transfer tube.

It’s assumed the transfer tube now doubles as the header tank for the landing burn.

 

[terkans]

Designate it Space Force One and gift it to Trump who recently told the Artemis II astronauts that he might want to go to space himself.

Space Force One-Way

 

[Cthel]

At what point does this become like buildings - occupied height vs. spire height etc?

If ULA wants to take the crown, just plop an unusually long "escape system" to the top of their rocket.

I wonder what the tradeoff looks like for a jettisonable aerospike to improve the aerodynamics of a blunt-nosed rocket?

(Presumably it comes down to the weight of the extra reinforcement it requires vs just making the nose of the rocket pointy the traditional way, which is why it's currently only found on length-limited rockets like the Trident 1 SLBM)

 

[Super3DPC]

I wonder why SpaceX never attempted a Starship launch for a full orbit but with perigee inside the atmosphere. That way they can try landing Starship on the ocean near its launch site, just like the booster. Is it because such orbit requires engine relight?

 

[Dtiffster]

This seems unlikely. This 2024 render from Chameleon Circuit shows an oxygen landing tank (wrapped around the base of the methane transfer tube) which was roughly that large, but the transfer tube was much smaller.
View attachment 134885
Perhaps for V3, the methane sump and manifold is 3.7m wide, but if the transfer tube is that wide, it's no longer just a transfer tube.

You're out of date

 

[hopkinssm]

I wonder why SpaceX never attempted a Starship launch for a full orbit but with perigee inside the atmosphere. That way they can try landing Starship on the ocean near its launch site, just like the booster. Is it because such orbit requires engine relight?

Because until they can show (to themselves) control of the starship during re-entry, any landing attempt into the Gulf would require approaching over populated areas.

 

[Chatskiy]

I wonder why SpaceX never attempted a Starship launch for a full orbit but with perigee inside the atmosphere. That way they can try landing Starship on the ocean near its launch site, just like the booster. Is it because such orbit requires engine relight?

Full orbit would have to pass over populated territory in California/Mexico/Texas.
This was deemed too risky.
Current plan is for "two successful "soft" ocean landings of the upper stage Starship before attempting a catch"

 

[stjns]

You're out of date

holy shit.

Is it possible that it is serving multiple functions now though? That just seems like an insane volume for a transfer tube?

 

[Helernus]

Brutal signal to noise ratio here

It's still early. Give some time for the voting system to do its job. After all, it's lot faster to type out a quip about Elon than it is to thoughtfully engage with the post and have informed discussions of rocketry.

 

[Chatskiy]

Is it possible that it is serving multiple functions now though? That just seems like an insane volume for a transfer tube?

It is also a landing header tank.

edit: Transfer tube + header tank + possibly extra structural element.
edit2: after all, after test mishap Booster 18 was still standing supported only by the transfer tube

 

[Demosthenes642]

The mention of record height got me wondering. How much taller is an empty stack in versus a fully fueled one? On something that size the thermal expansion/contraction must be a design consideration.

 

[Helernus]

Current plan is for "two successful "soft" ocean landings of the upper stage Starship before attempting a catch"

It seems to always take them a couple of attempts at least to work out the kinks with each new version. I would expect at least one RUD before they have a successful-enough flight to get an ocean landing of the upper stage.

 

[Ziv]

So they are changing the launch course from approximately 105° to 125°, (from overflying the Florida Strait to the Yucatan Strait).
Why? Are they increasing the inclination of the orbit to increase the amount of land covered? Or do they want to splashdown further south in the Indian Ocean?
Is the Yucatan Strait less traveled by aircraft and deemed to be safer? How high does a spacecraft need to be before overflight is effectively a non-issue? Would 100 km. be sufficient?
Sorry for the newby questions.

 

[fenris_uy]

and the first since last October, after delays in readying V3 for its first launch.

By "delays" you mean losing a first stage and second stage during testing.

 

[wagnerrp]

So let me get this straight - if we gut the government space program to pay for ~$100T in tax cuts for billionaires, 50 years after landing on the moon and 40 years after ending the Apollo program we'll be ready to test a rocket that is part of a test program to land on Mars, at a further cost of ~$30B (with no new capability provided except profit margins for said billionaires).

And all it cost us was 50 years and $100T.

Private space has been a complete and utter disaster.

I forgot about cheap internet for billionaire yachts, we have that too.

$30B? SpaceX is only getting $4B in funding for Starship/Artemis, and that includes payment for a demonstration and two operational missions.

 

[Chatskiy]

Is the Yucatan Strait less traveled by aircraft and deemed to be safer?

It seems to be.

 

[MacnCheese]

My back of the napkin math (ChatGPT) says that the booster's instantaneous propulsion power is roughly 140-160 gigawatts.

That is over twice the instantaneous power consumption of Germany.

Rough country comparisons:

• United Kingdom average electric demand: ~30–40 GW
• France: ~50–70 GW
• Japan: ~120–160 GW
• Germany: ~60–80 GW

 

[wagnerrp]

So they are changing the launch course from approximately 105° to 125°, (from overflying the Florida Strait to the Yucatan Strait).

They’re changing the launch course from ~90° to ~105°, from flying north of Cuba to flying south of Cuba.

Why?

Because they’ll need to launch to that trajectory to rendezvous with something launched from the Cape.

Are they increasing the inclination of the orbit to increase the amount of land covered?

There’s no significant overflight. This is north of the Yucatán, not over it.

How high does a spacecraft need to be before overflight is effectively a non-issue?

It’s a question of how long it takes for the debris to fall. There’s an exclusion zone and a DRA (debris response area). The exclusion zone is an immediate hazard during a launch. The DRA is a region in which the rocket should be high enough that you should be able to escape the falling debris before it reaches your altitude. It’s still an issue, but it’s not an immediate hazard.

 

[Speaking from Europe...]

I still remember when Elon Musk was publicly interviewed and he said he was building a rocket that would be bigger and more powerful than the ones Nasa used for the moon - a bunch of the people there were amazed, half of them thought he was full of shit and the rest thought he was crazy.

He really showed the non believers!

 

[Jedakiah]

holy shit.

Is it possible that it is serving multiple functions now though? That just seems like an insane volume for a transfer tube?

V3 has two major changes that appear to justify this.

1) All of the engines now begin firing simultaneously, there is no staged ignition. Static fires show two flashes, first from 33 preburners, then the subsequent big one comes from simultaneous chamber ignition. The transfer tubes go from moving nothing, to nearly instantly moving around 15tons/second of propellant! That gets them to their minimum throttle level. At max throttle it nearly doubles the amount of propellant flowing. Changes this quick can easily produce cavitation. To offset you widen the tubes.

2) Transfer tube pulls double duty as a landing header tank. Or as I like to call it: the footer tank.

 

[peterford]

Anyone know if v3 changes the autogenous pressurisation to prevent water ice and the resultant filter requirement?

 

[Redwood1]

Has any of these vehicles or elevators or all of these ideas even started to be developed by SpaceX?
https://www.popsci.com/science/starship-artemis-concept-art/

 

[Cthel]

[snip]
On-topic: isn't it amazing that the world's most powerful rocket ever can't get out of LEO without refueling! It is so counterintuitive. I guess the heavy weight of the steel is the culprit, but also the enabler of refueling and reuse.

The two-stage-to-orbit architecture, methalox fuel and low staging velocity is not good for payload energy-to-launch mass performance.

It is good on a payload-to-dollar basis though, which is the idea behind the gamble.

(There's no such thing as the "best" rocket design; it all comes down to what metrics you care about)

 

[normally butters]

By "delays" you mean losing a first stage and second stage during testing.

Yes, but Pad 2 readiness ended up being the long pole in the schedule anyway. If Booster 18 and Ship 38 had completed Massey's tests successfully, they'd have been waiting until now for the pad to be ready for booster static fire and full-stack wet dress rehearsal.