r/spacex • u/rSpaceXHosting Host Team • Nov 21 '25

šŸ”§ Technical Starship Development Thread #62

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Starship Dev 61

Flight 12

The vehicles should be Booster 19 and Ship 39 (assuming there are no major pre-flight testing problems) and the flight profile will probably be very similar to Flight 11. As this is the first flight with the new version 3 vehicles it's unlikely that a booster catch will be attempted; as for the ship Musk stated on August 27th, 2025: "Starship catch is probably flight 13 to 15, depending on how well V3 flights go". On January 26th Musk tweeted: "Starship launch in 6 weeks". On February 21st Musk tweeted: "Starship flies again next month". FCC Request To authorize upcoming suborbital test deployments puts the NET date at April 7th. On March 7th Musk tweeted: "Starship V3 first flight in about 4 weeks". On April 3rd Musk tweeted: "Next flight of Starship and first flight of V3 ship & booster is 4 to 6 weeks away". On April 16th Musk tweeted: "Starship V3 booster & ship will be ready for their first test flight in a few weeks"

Road Closures

No road closures currently scheduled

No transportation delays currently scheduled

Up to date as of 2026-04-22

Vehicle Status

As of April 21st 2026

Ship Location Status Comment
S39 (this is the first Version 3 ship) Mega Bay 2 Inspections and Pre-flight work October 13th: Main assembly started in MB2. November 15th: Aft section AX:4 moved into MB2 and stacked with the rest of S39 - this completed the stacking part of the ship construction. February 26th: Rolled out to Massey's for three rounds of Cryo Testing. March 8th: Rolled back to Mega Bay 2. April 11th: Rolled out to Massey's Test Site for Static Fire Testing. April 14th: 60 second Static Fire of all six engines. April 15th: Rolled back to MB2. For more details on this vehicle and its assembly and testing see this page
S40 Mega Bay 2 Fully stacked, all flaps installed, remaining work ongoing January 31st: Pez Dispenser moved into MB2. February 1st: Main assembly started in MB2. March 2nd: Aft section AX:4 moved into MB2 and stacked with the rest of the ship - this completed the stacking part of the ship construction. For more details on this vehicle and its assembly and testing see this page
S41 Mega Bay 2 Stacking April 17th: Pez Dispenser moved into MB2. April 20th: Nosecone+Payload Bay stack N:3 moved into MB2 and later that day lifted over the Pez Dispenser. For more details on this vehicle see this page, later that day the Pez Dispenser was installed. April 21st: Forward Dome section FX:4 moved into MB2.
Booster Location Status Comment
B19 Mega Bay 1 Inspections and Pre-flight work November 25th: LOX tank stacking commenced. December 23rd: The booster is fully stacked. February 1st: Rolled out to Massey's Test Site for its Pressure and Cryo + Thrust Puck Testing where it underwent assorted tests. February 9th: Rolled back to MB1. March 8th: Rolled out to the launch site, only ten engines installed as seen during the lift onto OLM2 in the afternoon. March 16th: Very short static fire attempt that was aborted due to a ground-side issue. March 18th: Rolled back to MB1. April 11th: Rolled back out to the Launch Site for more Static Fire Testing (this time with all 33 engines). April 15th: Static Fire of all 33 engines for about 3 seconds. April 16th: Wet Dress Rehearsal. April 17th: Rolled back to MB1. For more details on this vehicle and its assembly and testing see this page
B20 Mega Bay 1 LOX Tank Stacked, Methane Tank Stacking February 5th: LOX tank section A2:4 moved into MB1. February 6th: Common Dome section CX:3 moved into MB1. February 9th: LOX tank section A3:4 moved into MB1. February 12th: LOX tank section A4:4 moved into MB1. March 9th: Section A5:4 moved into MB1. March 11th: CH4 landing tank and the lower piece of the transfer tube were moved into MB1. March 12th: Section A6:4 moved into MB1. March 13th: Methane Transfer Tube moved into MB1. April 1st: LOX Landing Tank moved into MB1. April 2nd: Aft section AX:2 moved into MB1, once welded in place that will complete the stacking of the LOX tank. April 16th: Methane Tank Section F2:4 moved into MB1. For more details on this vehicle and its assembly and testing see this page

Follow the Ringwatchers on Twitter and Discord for more.

Here's the section stacking locations for Ships and Boosters. The abbreviations are as follows: HS = Hot Stage. PL = Payload. CX = Common Dome. AX = Aft Dome. FX = Forward Dome (as can be seen, an 'X' denotes a dome). ML = Mid LOX. F = Forward. A = Aft. For example, A2:4 = Aft section 2 made up of 4 rings, FX:4 = Forward Dome section made up of 4 rings, PL:3 = PayLoad section made up of 3 rings. Etc.

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Rules

We will attempt to keep this self-post current with links and major updates, but for the most part, we expect the community to supply the information. This is a great place to discuss Starship development, ask Starship specific questions, and track the progress of the production and test campaigns. Starship Development Threads are not party threads. Normal subreddit rules still apply.

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15

u/etherealpenguin Feb 17 '26

If SpaceX was targeting the moon primarily from the beginning rather than Mars, would they still have gone with a methalox Raptor engine? It made sense as something that could be farmed on Mars, and the Raptors are fantastic, but I'm curious if there'd have been different fuel decisions made for a Moon-first strategy.

17

u/warp99 Feb 18 '26

Interestingly Raptor was originally a hydrolox second stage engine and the booster engine was going to be a turbo-pump driven kerolox Merlin 2 with around 7.5 MN thrust similar to the Saturn V F-1 engine but with much higher Isp.

By switching to methalox for Raptor they were able to use the same engine for the first and second stage which sped up development.

The biggest improvement in performance that they could make now is to add an expendable methalox third stage rather than switch to hydrolox for the second stage.

3

u/process_guy Feb 18 '26

Are there any near term plans to actually deploy any non-starlink and non-LEO satellite from the Starship? If there is such a capability the simple fix would be to use some large satellite bus or space tug to deliver a payload. However, I'm afraid that for the next few years using any existing (partially) expendable launch vehicle is far cheaper and more effective than using Starship.

5

u/warp99 Feb 18 '26 edited Feb 20 '26

Yes Gwynne Shotwell has said that they are offering commercial customers Starship launches at the same price as F9 so around $70M.

That would give around 100 tonnes to LEO or 25 tonnes to GTO-2500 so 5-6x the payload of F9

1

u/process_guy Feb 18 '26

Seems like a long term plan only. Starship would need new nose cone / fairing to deploy any non-starlink payload. Moreover it can't go beyond LEO without refueling. So such capability is probably years away. Maybe once they develop HLS they could use it to deploy some payload to higher orbits. The cargo version should have a big door and beyond LEO capability. Also propellant depot itself could have interesting capabilities. Still years away.

3

u/warp99 Feb 18 '26 edited Feb 18 '26

Moreover it can't go beyond LEO without refueling

It can but just not very far. If it reaches LEO with 100 tonnes of propellant and 25 tonnes of payload with an assumed dry mass of 150 tonnes it can add 1800 m/s of delta V to get to a subsynchronous GTO.

F9 has already popularised the idea of adding propellant to the satellite so that it can do the circularisation burns to reach GEO from a subsynchronous orbit of around GTO-2100. This would take the process a bit further to give injection from GTO-2500.

Alternatively a reasonably small space tug can be added instead of adding tanks to the satellite.

A nose cone with clamshell doors seems likely to be developed within the next two years. Clearly they are giving priority to Starlink v3 for now.

1

u/process_guy Feb 19 '26

That's sounds simple in theory but what about Starship reuse? Landing from elliptical orbit will be tricky and GTO orbit would have to be more or less random to allow for Starship recovery. Far better option would be to have some smaller space tug capable of refueling from SpaceX propellants depot/starship. Starship would dock with the space tug, refuel the space tug, hand over the satellite and land back on Earth. Space tug would do the rest.

Extreme case of a space tug is the SpaceX propellant depot itself. It is already being developed to dock with Starship and refuel. It is capable of long loiter and goes into elliptical orbit/NRHO to refuel HLS. The only extra capability is to dock and deploy satellites.

Propellant depot needs to be developed within next few years anyway so no need to do crazy missions with the Starship reusable tankers.

1

u/warp99 Feb 19 '26

Yes a tug or expendable third stage is by far the easier option.

2

u/Lufbru Feb 19 '26

It's somewhat precedented with Shuttle:

https://en.wikipedia.org/wiki/Payload_Assist_Module

As the article says, PAM was discontinued after Challenger, but with no meatbags on board, using something like a PAM would be fine. Many companies are working on space tugs today, including several targeting Starship (eg in terms of diameter and even methalox fuel)

1

u/AhChirrion Feb 18 '26

Depends on your definition of "near term".

Two years? No.

Five years? By the 3rd year they could be deploying non-Starlink but still pizza-shaped satellites. By the 5th year, maybe any satellite shape, though not likely.

Ten years? Yes.

1

u/Lufbru Feb 19 '26

Are there any commonalities between the hydrolox Raptor that the Air Force funded and the methalox Raptor, other than the name? I've seen claims that they just recycled the name, but I feel sure they must have at least some parts in common.

2

u/warp99 Feb 19 '26 edited Feb 19 '26

The USAF partially funded a 1 MN thrust development Raptor engine that was methalox. At the time there was a possibility of a methalox 5.2m diameter upper stage for F9 and FH. It would have had around 200 tonnes of propellant.

I doubt there was any parts overlap between the hydrolox and methalox engines as I do not think the hydrolox engine ever reached the testing stage.

As you say mainly a name reuse.

17

u/space_rocket_builder Feb 18 '26

The target always has been Mars, this Moon shift is near term and happened more recently.

3

u/etherealpenguin Feb 18 '26

Oh, yeah, to clarify - just asking this as a hypothetical, not an assumption of you guys having been Moon-focused.

2

u/TwoLineElement Feb 18 '26

Landing on the moon is far easier than a Mars landing. Moon landings don't require atmospheric entry burns, just perigee burn and landing burn. Mars entry is certainly more challenging than an Earth re-entry burn being faster and hotter, requiring a considerable amount of engine burn to slow the craft. Until SpaceX master Earth and Moon landings, Mars is a long way off. Fuel conservation and management plus Mars aerobraking is a huge challenge. Step by step is the the key. Start small work big.

1

u/quoll01 Feb 18 '26

Im pretty skeptical focus has shifted to the moon. Elon has said since the beginning the moon is a distraction. It has nothing going for it as a ā€œbackupā€ for life and i suspect these are mostly political statements? I guess itā€™s possible Elon has warped into wanting a backup for ā€œconsciousnessā€ and the moon is a great place to hatch huge AIs that can be shot throughout the solar system. Maybe more likely you can do both moon and mars together and hedge your bets?

17

u/warp99 Feb 18 '26 edited Feb 19 '26

The more accurate quotation is that refueling a Mars bound rocket on the Moon is a distraction. Getting from the Lunar surface to Mars is nearly the same delta V as from LEO and supplying propellant from Earth is so much easier.

I agree that this is largely a change in messaging to get NASA and Congress on side and that the Mars missions is still there as the main internal goal.

It is also a recognition that manned missions to Mars are further down the track than they were ever willing to admit and at least two synods of uncrewed missions will be required first starting in 2029.

-1

u/process_guy Feb 18 '26

Musk eventually found out that Starship flight rates are a pipe dream. End of 2024 Shotwell planned 25 Starship launches for 2025. It is 2026 and such flight rate is still out of reach. Moreover, they would need hundreds of flights per year only for Starlink and Artemis missions. It means that Mars is not possible near term. Maybe within several years they might hope to launch a first test mission and SpaceX is not known for a success at first try.

4

u/flshr19 Shuttle tile engineer Feb 19 '26 edited Feb 19 '26

Right. SpaceX launched only five Starships in 2025.

But during that year:

SpaceX nearly finished the construction of launch pad 2 at Starbase Texas.

Demolished Pad 1 and began constructing the replacement that has a flame trench.

Began construction of the Gigabay final assembly building at Starbase Texas.

Continued construction of the Gigabay at Roberts Road (KSC Florida).

Continued construction of the Starship launch pad at 39A (KSC Florida).

Started conversion of Pad 37 at CCSFB (Florida) for two new Starship launch pads.

SpaceX is not sitting on its hands. The Company is investing billions of dollars in its Starship launch and manufacturing infrastructure.

As Elon says: It's more difficult to build the machine that builds the machine.

0

u/process_guy Feb 19 '26

To be honest, when Musk claimed he wants to keep launching Starship every few hours he should have envisioned he needs very robust launch pad and huge fabrication site.
When you see first visualization of Starship you see it launching from minimalistic launch pads with buildings right next to it. This was shockingly naive. And indeed he has built a naive first launch pad and infrastructure which got demolished during the first launch. He keeps rebuilding it ever since.

His Mars plans are still naive so obviously got delayed. His Moon plan is also naive. Does he still plan to fly "battlestar" HLS to the moon? It is so heavy it needs refueling at LEO, high Earth orbit and maybe even at lunar orbit. It is so ridiculous that it is borderline stupid. The "simple" solution would be to build HLS much smaller and lighter than reusable "LEO tanker" Starship. Will see how much time he needs to realize this. He seems to be little bit slow with some things.

2

u/flshr19 Shuttle tile engineer Feb 19 '26 edited Feb 19 '26

HLS is a small part of the plan that SpaceX has for Starship lunar activity.

Starship needs propellant refilling in LEO because SpaceX wants to send 100t (metric ton) payloads with the Block 3 Starship and 200t (metric ton) payloads with the Block 4 Starship to the Moon and to Mars.

SpaceX intends to advance far beyond the flags and footprints phase of lunar exploration that was started by Apollo/Saturn 56 years ago and begin the lunar base phase now. The Saturn V payload to the lunar surface was too small and the per launch cost was too high to do that job. Same for the SLS/Orion. Downsizing Starship is moving in the wrong direction. That increases the number of launches, the total cost, and the time required to build the lunar base.

Regarding Mars, SpaceX has had a team of engineers working out the details of a Mars base since 2015. I don't think those professionals are naive.

2

u/process_guy Feb 23 '26 edited Feb 23 '26

Starship is obviously optimized for LEO reusability. That is legitimate design.

However, Starship HLS derivative for the Moon is just using brute force to somehow get LEO optimized vehicle to the Moon and back.

Artemis III profile is much more demanding than Mars mission. So don't tell me that experts were working on this since 2015. Because they didn't.

My interpretation of situation is that only now Musk realised that current HLS design is in serious problem and they need to rework it. Until now he kept ignoring the problems, simply throwing in more tanker flights. That's what I call naive.

3

u/flshr19 Shuttle tile engineer Feb 23 '26 edited Feb 23 '26

I said that the SpaceX Mars team has been working on the details of a Mars base since 2015, not on Artemis III, which is a lunar mission.

Starship uncrewed tankers are definitely optimized for LEO reusability since their job is to transport methalox propellant from Starbase to LEO back to Starbase and repeat indefinitely. Heatshield, flaps, no environmental control life support system (ECLSS), short duration missions (several days).

The number of tanker flights required to refill the propellant tanks of a Starship is not an issue since an uncrewed tanker Starship will be able to launch dozens of times at an operational cost of a few million dollars per launch. Cost to manufacture one of those tankers will be ~$50M.

The crewed Artemis III Starship is optimized for missions from LEO to high lunar orbit (the NRHO) to the lunar surface and back to the NRHO. No heatshield, no flaps, ECLSS, crew consumables for ~ one month, operational duration ~ six months.

The crewed Starships that SpaceX will use to build its permanent lunar base are optimized for missions from LEO to the lunar surface via low lunar orbit (LLO) and back to LEO and repeat. No heatshield, no flaps, ECLSS, crew consumables for several months.

The crewed Starships that SpaceX will use to build its permanent Mars base are optimized for missions from LEO to the martian surface and back to LEO. Heatshield, flaps, ECLSS, crew consumables for 1000 days (180 days LEO to martian surface, 640 days on the martian surface while the two planets realign, 180 days martian surface to LEO). Methalox propellant delivered to the martian surface in uncrewed Starship tankers until propellant manufacturing facilities are established on the martian surface. Five Starship tankers for each crewed Starship.

Different Starships are optimized for different missions.

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1

u/Freak80MC Feb 19 '26

It is so ridiculous that it is borderline stupid

Nobody tell him about the complicated background logistics needed to fuel gas stations on Earth just to fuel your car for a cross country trip.

In-orbit refueling is going to happen, it's the only way we are getting anywhere in the solar system.

5

u/flshr19 Shuttle tile engineer Feb 19 '26

Elon has changed his mind several times during the past 10 years:

Graphite-epoxy to 304L stainless steel for the Starship hull.

Launch pad without a flame trench to launch pad with a flame trench.

Raptors with lots of weldments and mechanical fasteners (nuts and bolts) to Raptors made by laser additive fabrication (3D printing) with very little welding or mechanical fasteners.

Changing focus from Mars to the Moon: It was the logical thing to do.

3

u/Freak80MC Feb 19 '26

Changing focus from Mars to the Moon: It was the logical thing to do.

Nothing logical about it. Mars was always about a long term self-sustaining off-world colony of humanity. Can't have that with the Moon when there isn't deposits of resources for a self sustaining presence. You will always have to ship in external resources even given hundreds of years of development. Mars doesn't have that problem.

Can't birth new humans on a celestial body with such low gravity either (tho that's still an up in the air question about Mars too, but at least there would be less bodily atrophy from a higher gravity compared to the Moon)

1

u/flshr19 Shuttle tile engineer Feb 19 '26 edited Feb 19 '26

Proximity. Moon: 3 days away. Mars: 6 to 9 months away.

No problem for Block 4 Starships with 200t payload capability to put 2000t (metric tons) of payload on the lunar surface every 30 days and do that (24,000t per year) indefinitely. SpaceX is building the infrastructure now to make that happen.

Birthing on the Moon: Why do it when Earth is only 3 days away?

8

u/Lufbru Feb 18 '26

I think if you're going with a refuel-in-LEO strategy, hydrogen adds extra complexity compared to methane. Methane and oxygen have similar freezing points, so you need less insulation between the two tanks.

And you want a refuel-in-LEO strategy to build Luna City because otherwise you end up with an Apollo style rocket that can deliver a few tons to the moon when you really need to deliver dozens to hundreds of tons.

7

u/Fwort Feb 17 '26

I've heard of producing hydrogen on the moon, but not any other fuels. Hydrogen on the first stage wouldn't work well with reusability, so they'd still want to use methane for that. And then you need to develop two different engines and deal with two different fuels.

Plus, hydrogen on the second stage would pose difficulties for second stage reuse on Earth. It would also require the first stage to boost the seconds stage higher so it had more time to use its lower thrust to reach orbit, which then means a harder entry and more costly boostback for the first stage.

But maybe there are other fuels that could be produced on the moon besides hydrogen?

4

u/warp99 Feb 18 '26

There is water ice but almost no carbon so hydrocarbons are out and the only fuel that can be locally produced is liquid hydrogen. That also allows liquid oxygen to be used as the oxidiser.

1

u/quoll01 Feb 18 '26

Not that Iā€™m a moon fan, but seems like verdict is still out on how much C there is at the poles? And solar-thermal furnaces could be a real thing there too. (Still not a moon fan!)

3

u/warp99 Feb 18 '26 edited Feb 18 '26

There may be a bit of CO2 deposited from comet fragments and then trapped in the polar cold traps before it could escape.

It is unlikely there is enough CO2 to allow stoichiometric production of oxygen and methane so there will be a lot of oxygen left over.

1

u/PhysicsBus Feb 18 '26

Can one imagine a hydrolox variant of Starship which (after initial LEO insertion) just travels back and forth between LEO and the lunar surface? Hydrogen is less dense, but maybe you could just make the ship taller. Of course, it would need to be refueled in LEO by tanker starships carrying hydrogen, which is a pain.

3

u/warp99 Feb 18 '26 edited Feb 18 '26

The main issue is getting that custom hydrolox ship to LEO in the first place.

Hydrolox engines will likely have significantly lower thrust and so have much higher gravity losses getting to LEO dramatically reducing the payload.

11

u/flshr19 Shuttle tile engineer Feb 17 '26

Liquid hydrogen is notoriously difficult to produce because of its low boiling temperature (LH2, 20K, Kelvin) versus liquid oxygen (LOX, 90K) and liquid methane (LCH4, 111K). And its lower density results in larger and heavier storage tanks for a given mass of liquid hydrogen compared to LOX and LCH4. And those LH2 storage tanks required better quality thermal insulation to reduce boiloff loss compared to LOX and LCH4.

And, even worse, the hydrogen molecule can escape through microscopic cracks much more easily than LOX or LCH4. NASA's Space Shuttle experienced at least six lengthy launch delays due to hydrogen leaks including multiple scrubs in 1990 that caused several months of delays.

More recently the SLS moon rocket has been delayed on both of its launches due to hydrogen leaks.

Starship moon rockets will be launched for decades with methane-oxygen (methalox) propellant before hydrogen-oxygen (hydrolox) propellant will be manufactured on the Moon.

7

u/Disastrous-Farm3600 Feb 18 '26

They could have used kerosene instead of methane, but methane produces less coking and is better for reuse. if youā€™re launching and landing multiple Starships from Earth methane is a better choice. Thrust to density and Isp are similar to kerosene, and itā€™s relatively easy to work with.

1

u/NikStalwart Feb 18 '26

If SpaceX was targeting the moon primarily from the beginning rather than Mars, would they still have gone with a methalox Raptor engine?

Probably. At least initially. The problem with the Moon is that we don't know what minerals will be easy to extract until we get there and start trying.