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NASA recently made a presentation at some conference that revealed interesting information.

They say that they expect Starship's fourth orbital test flight (OFT-4) to take place before the end of May.

And there was this very informative briefing slide about the on-orbit ship-to-ship fuel transfer experiment to take place next year in 2025.

It involves two Starships in orbit at once such that the second homes in on and docks with the first, then transfers propellant to it. Both are to be launched from Starbase, which raises some questions. How quick succession between launches are they anticipating? How quickly can the launch pad and ground support equipment be turned around for a second launch?

NASA says that the docking mechanism and quick disconnects (the physical connections through which fuel will flow) are currently in development.

Today Ship 30, the OFT-5 ship, performed what appeared to be a flawless static fire.

SpaceX photo



nsNS

The Coast Guard has issued a marine safety warning for May 16. It's believed that this might be for a "wet dress rehearsal" for the upcoming OFT-4 launch, in which a fully stacked vehicle is loaded with actual propellant and a count-down is conducted without an actual launch ignition.

The Starfactory's roof is complete

This is its final footprint (or at least as final as anything at Starbase, it could change tomorrow).

Note the office building under construction in the lower right, and the parking structure under construction in the lower left.

(Photo by RGV Aerial Photography)

B11, the OFT-4 booster, rolled out to the launch site last night.

(SpaceX photo)



And placed on the launch mount this morning

(Photo by Base Camp Zero)

Yesterday they were cryo-testing S31 (with LN2) at Masseys when a bright spot of flame appeared on the side of the ship. It's believed that it was an electrical fire located along a 'raceway' (where electrical cabling goes up and down the ship.) The tanks didn't rupture and detanking the liquid Nitrogen seemed to proceed uneventfully. The SpaceX drone was spotted aloft getting closeup imagery of the site of the fire. A blackened spot was visible afterwards.

Video here:

https://twitter.com/NASASpaceflight/stat...3335943209

My guess is that they will hold off stacking the OFT-4 vehicles until they are sure they understand the cause of the S31 fire and are confident that S29 won't require any changes.

They stacked the OFT-4 vehicle today: Ship 29 on top of Booster 11.

It's expected to undergo a Wet Dress Rehearsal in the next couple of days. Then we expect S29 to be destacked and roll back to the Bays, for finishing tile work.

(SpaceX photo)

The WDR is now scheduled for Saturday. Today was devoted to testing their ground support equipment.

And another tower segment (arrived from Cape Canaveral several months ago) has been moved from the Port of Brownsville to the Hwy 4 (the Boca Chica road) junction. It will be moved to the Sanchez part of Starbase tonight about midnight local, when its less disruptive to close the road.

(Photo by RGV Aerial)



(Photo by Starship Gazer)



These tower sections are destined to become the second launch tower at the launch site at Starbase.

The WDR is underway as I write this. Both ship and booster have been fully tanked and are starting to detank.

And... it's successfully concluded. This wasn't just a tanking test, it was a complete countdown rehearsal, up to right before launch. (Then a detanking rehearsal, which would be necessary in the event of a scrub.)

SpaceX photo

There are rumors swirling...

One is that SpaceX is aiming to launch OFT-4 on June 1. This is based on NASA's WB-57 photography and tracking plane being reserved for an undisclosed mission on that date. (That's what typically happens before launches.)

Another rumor is that SpaceX wants to conduct two launches in June. I don't know the source for this one. It initially sounds unbelievable, but it isn't totally outlandish, given that next year's orbital refueling demonstration will require two launches from Starbase in quick succession and now is arguably the time to perfect quick launch turn around.

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Elon (sorta, kinda) confirms an OFT-4 launch date around the beginning of June

Starship Flight 4 in about 2 weeks.

Primary goal is getting through max reentry heating.

Worth noting that no one has ever succeeded in creating a fully reusable heat shield. Shuttle required >6 months of rework.

https://x.com/elonmusk/status/1792629142141177890