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BFR Developments

Yazata Offline
Over the last few days, several extraordinary fan-videos have come out. First there was Space Sudoer's very moving love-song to Starbase and to everything it represents.

And here is one from Marcus House in far-off Tasmania, Australia's island state. (Space-nuts are a world-wide clan.) This takes audio of Elon's recent presentation to the assembled Starbase employees, and provides illustrations of all the things that Elon is saying.

If you were ever a science-fiction nut, you can't help being moved by this.
Yazata Offline
Eric Berger of Ars Technica is reporting that the FAA told him that SpaceX is asking the FAA for approval to perform "at least" nine Starship launches this year!

We all know that there are already multiple ships and boosters at Starbase, just waiting for their chance to be flung at the sky. What's more, development of the HLS lander for Artemis along with the orbital refueling upon which it all depends, demands lots of development flights if everything is to be completed on time. So not only Elon, but also NASA and probably the Space Force as well, want the pace to accelerate. Which puts the FAA in the uncomfortable position of having to rewrite their procedures, in full knowledge that if anythings goes wrong, they will be among those blamed.

(highlighting by me)

"As SpaceX nears its first Starship launch of 2024—possibly as soon as within three weeks—from its Starbase facility in South Texas, the company is pressing regulators to increase its cadence of flights.

During a press availability this week, the administrator for Commercial Space Transportation at the Federal Aviation Administration, Kelvin Coleman, said the agency is working with the company to try to facilitate the Starship launch-licensing process.

"They're looking at a pretty aggressive launch schedule this year," he said. "They're looking at, I believe, at least nine launches this year. That's a lot of launches. If you're doing modifications and doing them one by one, that's a lot of work. We've been talking to SpaceX constantly around the clock, coming together and trying to figure out how do we do this. We're invested with the company, and so we'll work with them to get them back going as soon as they can..."
C C Offline
^ ^ ^ ^ ^

It's nice to know that all relevant agencies and parties at least have some kind of clue.

I mean, before one even allows a Starbase to be built that's going to be assembling and regularly launching giant rockets, the various concerns for that area need to be identified, addressed, and the changes, strategies and preparations settled that will need to be implemented. You don't wait till Godzilla has already built its massive château beside a bay, and is ready to party with other monster guests, and start blowing fire, before you even begin considering if it was a good idea.
Yazata Offline
The location of the second orbital launch tower and orbital launch mount have been revealed in an obscure Army Corps of Engineers filing.

"SpaceX reinitiated the permit application on 12 February 2024 with modified project plans requesting to fill a 0.16 acre wetland to construct a second orbital launchpad which will replace the current suborbital launch pad and test stand...."

It doesn't really come as any surprise to Starbase watchers since SpaceX has been telegraphing their intentions for some time, not least by moving the suborbital side's cryo testing and ship static fire functions to Masseys.

[Image: GG-cq_HW8AALVoL?format=jpg&name=900x900]
[Image: GG-cq_HW8AALVoL?format=jpg&name=900x900]

Yazata Offline
The FAA just sent SpaceX this:

"Following a successful start-up of all engines and separation from B9, Starship Ship 25 (S25) had a nominal ascent until 13:09:55 UTC, when the planned pre-second engine cutoff Liquid Oxygen dump started. Over the next minute, several explosions and sustained fires were observed in onboard camera aft video streams, ultimately resulting in a loss of communication between the forward and aft flight computers. This resulted in a commanded shutdown of all six engines, and an Autonomous Flight Safety System flight termination triggering at 13:10:55 UTC per flight safety rules...

...The FAA has been provided with sufficient information and accepts the root causes and corrective actions described in the mishap reports. Consequently, the FAA considers the mishap investigation that SpaceX was required to complete to be concluded."

Now that SpaceX's proposed mitigations have been accepted by the FAA, SpaceX still needs to demonstrate to the FAA that they have been completed on the IFT-3 vehicles before the FAA will grant a license. I think that we can assume that they have already been completed or are currently underway, so this shouldn't take long.

[Image: GHS4y1QawAA5Rr4?format=jpg&name=large]
[Image: GHS4y1QawAA5Rr4?format=jpg&name=large]

SpaceX posted this today on the 'updates' section of their website today:

"The second flight test of Starship and Super Heavy achieved a number of important milestones as we continue to advance the capabilities of the most powerful launch system ever developed.

On November 18, 2023, Starship successfully lifted off at 7:02 a.m. CT from Starbase in Texas. All 33 Raptor engines on the Super Heavy Booster started up successfully and, for the first time, completed a full-duration burn during ascent. Starship then executed a successful hot-stage separation, the first time this technique has been done successfully with a vehicle of this size.

Following stage separation, Super Heavy initiated its boostback burn, which sends commands to 13 of the vehicle’s 33 Raptor engines to propel the rocket toward its intended landing location. During this burn, several engines began shutting down before one engine failed energetically, quickly cascading to a rapid unscheduled disassembly (RUD) of the booster. The vehicle breakup occurred more than three and a half minutes into the flight at an altitude of ~90 km over the Gulf of Mexico.

The most likely root cause for the booster RUD was determined to be filter blockage where liquid oxygen is supplied to the engines, leading to a loss of inlet pressure in engine oxidizer turbopumps that eventually resulted in one engine failing in a way that resulted in loss of the vehicle. SpaceX has since implemented hardware changes inside future booster oxidizer tanks to improve propellant filtration capabilities and refined operations to increase reliability.

At vehicle separation, Starship’s upper stage successfully lit all six Raptor engines and flew a normal ascent until approximately seven minutes into the flight, when a planned vent of excess liquid oxygen propellant began. Additional propellant had been loaded on the spacecraft before launch in order to gather data representative of future payload deploy missions and needed to be disposed of prior to reentry to meet required propellant mass targets at splashdown.

A leak in the aft section of the spacecraft that developed when the liquid oxygen vent was initiated resulted in a combustion event and subsequent fires that led to a loss of communication between the spacecraft’s flight computers. This resulted in a commanded shut down of all six engines prior to completion of the ascent burn, followed by the Autonomous Flight Safety System detecting a mission rule violation and activating the flight termination system, leading to vehicle breakup. The flight test’s conclusion came when the spacecraft was as at an altitude of ~150 km and a velocity of ~24,000 km/h, becoming the first Starship to reach outer space.

SpaceX has implemented hardware changes on upcoming Starship vehicles to improve leak reduction, fire protection, and refined operations associated with the propellant vent to increase reliability. The previously planned move from a hydraulic steering system for the vehicle’s Raptor engines to an entirely electric system also removes potential sources of flammability.

The water-cooled flame deflector and other pad upgrades made after Starship’s first flight test performed as expected, requiring minimal post-launch work to be ready for vehicle tests and the next integrated flight test.

Following the flight test, SpaceX led the investigation efforts with oversight from the FAA and participation from NASA, and the National Transportation and Safety Board.

Upgrades derived from the flight test will debut on the next Starship and Super Heavy vehicles to launch from Starbase on Flight 3. SpaceX is also implementing planned performance upgrades, including the debut of a new electronic Thrust Vector Control system for Starship’s upper stage Raptor engines and improving the speed of propellant loading operations prior to launch.

More Starships are ready to fly, putting flight hardware in a flight environment to learn as quickly as possible. Recursive improvement is essential as we work to build a fully reusable launch system capable of carrying satellites, payloads, crew, and cargo to a variety of orbits and Earth, lunar, or Martian landing sites."

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