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(May 16, 2025 07:41 PM)Yazata Wrote: [ -> ]An interesting detail is that Booster 14.2, the first reflown Superheavy booster, won't be attempting a second tower catch, but instead will be soft landing expendably in the Gulf of America.

Is that just an easier way to retire it, in favor of the next version?

(May 16, 2025 10:45 PM)Syne Wrote: [ -> ]

(May 16, 2025 07:41 PM)Yazata Wrote: [ -> ]An interesting detail is that Booster 14.2, the first reflown Superheavy booster, won't be attempting a second tower catch, but instead will be soft landing expendably in the Gulf of America.

Is that just an easier way to retire it, in favor of the next version?

I don't know.

Perhaps they want to see how a reflown booster performs before they risk a catch. That's my guess.

My understanding is that they will be using the original model boosters for several more flights. They have several all constructed and waiting in the vertical assembly bays.

The new model boosters aren't compatible with original Pad A, so they can't be flown until the new Pad B is completed. Then Pad A will be torn apart and reconstructed to Pad B specifications.

Besides the new booster tank design is still in structural testing, so the new boosters aren't quite ready for prime-time yet.

Ah, that would make sense.

A big party on top of Megabay-2. Apparently, it's a SpaceX engineers' wedding.

In other news... Space Balls!

They are huge bags of water to create mass to load-test the Pad B "chopstick" tower arms.

Hence: Testicles!

(Photo by Starship Gazer)



(Photo by Carlos Nunez)

The city of Brownsville says

SpaceX’s Starship is expected to launch its Ninth Test Flight.
Here’s what you need to know:
Launch Window: Tuesday, May 27, Time: TBD
Sonic Booms: Possible in Brownsville, South Padre Island, and Port Isabel

https://x.com/BTxRGV/status/1924923183079014598

---

The new Pad B launch mount.

The part depicted here is where the propellants feed into the booster quick disconnects for tanking/detanking, and where high pressure gasses are fed into an onboard manifold in order to spin up the turbopumps of the outer ring of 20 raptor engines. (The inner 13 engines, that have to relight in flight, are spun up by gas in high pressure bottles carried by the booster.) There's lots of electrical controls and valves in this part of the launch mount. There's speculation that it might be covered by steel armor when it's completed to protect it from the ascending rocket's exhaust plume.

(Photo by Starship Gazer)



nsNS

The FAA has approved Starship's Return to Flight!

They say:

"FAA Approves SpaceX Starship Vehicle Return to Flight

The FAA conducted a comprehensive safety review of the SpaceX Starship Flight 8 mishap and determined that the company has satisfactorily addressed the causes of the mishap, and therefore, the Starship vehicle can return to flight. The FAA will verify SpaceX implements all corrective actions.

The FAA’s determination of when a vehicle involved in a mishap can resume operations is based on public safety. When making this determination, the FAA considers several factors, including but not limited to, the nature of the mishap, the performance of vehicles safety-critical systems, and the generation of unplanned debris. Prior to making a return to flight determination, the FAA must find that any system, process, or procedure related to the mishap does not affect public safety or any other aspect of the operator’s license.

With the Starship vehicle return to flight determination, Starship Flight 9 is authorized for launch. The FAA finds SpaceX meets all of the rigorous safety, environmental and other licensing requirements."


https://www.faa.gov/newsroom/statements/...statements

NASASpaceflight.com just put out this helpful and entertaining little video explaining a bunch of the jargon that the space nerds (and the professionals) toss around. BQD, SQD, OLM, OLIT, GSE, SPMT and many more. Narrated by the always likeable John Galloway ("Das")

SpaceX just posted an account of the Flight 8 failure.

It's important to note that while the Flight 7 and Flight 8 failures occurred at the same point in the Ship's boost to orbit, the failures had distinctly different causes.

They say:

"On March 6, 2025, Starship’s eighth flight test successfully lifted off at 5:30 p.m. CT from Starbase in Texas...

Starship’s upper stage flew along its expected trajectory following separation from the Super Heavy booster. Approximately five and a half minutes into its ascent burn, a flash was observed in the aft section of the vehicle near one of the center Raptor sea level engines followed by an energetic event that resulted in the loss of the engine. Immediately after, the remaining two center Raptor engines and one of the Raptor vacuum engines shut down and vehicle control authority was lost. Telemetry from the vehicle was last received approximately nine and a half minutes into the flight, or a little more than two minutes following the first flash observation, at which point all engines had shut down...

The most probable root cause for the loss of Starship was identified as a hardware failure in one of the upper stage’s center Raptor engines that resulted in inadvertent propellant mixing and ignition. Extensive ground testing has taken place since the flight test to better understand the failure, including more than 100 long-duration Raptor firings at SpaceX’s McGregor test facility.

To address the issue on upcoming flights, engines on the Starship’s upper stage will receive additional preload on key joints, a new nitrogen purge system, and improvements to the propellant drain system. Future upgrades to Starship will introduce the Raptor 3 engine which will include additional reliability improvements to address the failure mechanism.

While the failure manifested at a similar point in the flight timeline as Starship’s seventh flight test, it is worth noting that the failures are distinctly different. The mitigations put in place after Starship’s seventh flight test to address harmonic response and flammability of the ship’s attic section worked as designed prior to the failure on Flight 8...."

https://www.spacex.com/updates/

SpaceX posted more details about Flight 9:

https://www.spacex.com/launches/mission/...p-flight-9

"The ninth flight test of Starship is preparing to launch as soon as Tuesday, May 27. The launch window will open at 6:30 p.m. CT.

A live webcast of the flight test will begin about 30 minutes before liftoff, which you can watch here and on X @SpaceX. You can also watch the webcast on the X TV app...

The upcoming flight test marks the first launch of a flight-proven Super Heavy booster, which previously launched and returned on Starship’s seventh flight test...

...extensive inspections took place following the booster’s first launch to assess hardware health and identify where maintenance or replacement hardware was needed. Known single-use components like ablative heat-shielding were replaced, but a large majority of the booster’s hardware will be flight-proven, including 29 of its 33 Raptor engines. Lessons learned from the first booster refurbishment and subsequent performance in flight will enable faster turnarounds of future reflights...

Following stage separation, the booster will flip in a controlled direction before initiating its boostback burn. This will be achieved by blocking several of the vents on the vehicle’s hotstage adapter, causing the thrust from Starship’s engines to push the booster in a known direction. Previous booster flips went in a randomized direction...

After the conclusion of the boostback burn, the booster will attempt to fly at a higher angle of attack during its descent. By increasing the amount of atmospheric drag on the vehicle, a higher angle of attack can result in a lower descent speed which in turn requires less propellant for the initial landing burn. Getting real-world data on how the booster is able to control its flight at this higher angle of attack will contribute to improved performance on future vehicles...

Finally, unique engine configurations will be demonstrated during the Super Heavy’s landing burn. One of the three center engines used for the final phase of landing will be intentionally disabled to gather data on the ability for a backup engine from the middle ring to complete a landing burn. The booster will then transition to only two center engines for the end of the landing burn, with shutdown occurring while still above the Gulf of America and the vehicle expected to make a hard splashdown.

The Starship upper stage will again target multiple in-space objectives, including the deployment of eight Starlink simulators...

The flight test includes several experiments focused on enabling Starship’s upper stage to return to the launch site. A significant number of tiles have been removed from Starship to stress-test vulnerable areas across the vehicle during reentry. Multiple metallic tile options, including one with active cooling, will test alternative materials for protecting Starship during reentry. On the sides of the vehicle, functional catch fittings are installed and will test the fittings’ thermal and structural performance. The entire ship's tile line also received a smoothed and tapered edge to address hot spots observed during reentry on Starship’s sixth flight test. Starship’s reentry profile is designed to intentionally stress the structural limits of the upper stage’s rear flaps...

Assuming that everything progresses according to plan, Starship flies tomorrow at 6:30 PM CDT.

(Nasaspaceflight.com photo)



(SpaceX photo)