SpaceX is about to have a fleet of Starship rockets

[F-22Raptor]

SpaceX has finished the last major stacking event for the business half of its fifth full-scale Starship prototype, meaning that the company may be a week or less from having a fleet of Starships for the first time ever.

As of now, Starship serial number 5 (SN5) is on track to be completed in under a month, continuing a trend that SpaceX has managed over the entirety of 2020. Beginning in mid-January, SpaceX has completed several nosecone pathfinders, three test tanks, and three full-scale Starship prototypes – soon to be four once SN5 is finished. Once it is, however, SpaceX will be entering a new era of operations – fleet operations.

Up to this point, every full-scale Starship prototype and test tank SpaceX has built – excluding the tank SN2 was turned into in March – has been quickly destroyed over the course of one or two tests. For better or for worse, this has meant that SpaceX’s test and launch pad has always been more or less self-clearing, making way for the next prototype to roll out and begin testing after the scraps of its predecessor were removed. This time around, barring Starship SN4’s imminent demise, SpaceX will now have to deal with multiple completed Starship prototypes at the same time – a tiny taste of things to come.

For unknown reasons, SpaceX decided to swap out Starship SN4’s lone Raptor engine (likely SN18) after multiple wet dress rehearsals, partial engine tests, and two static fire tests – at least one of which was confirmed a success by CEO Elon Musk. Most recently, SpaceX removed Raptor SN18 to perform a more ambitious cryogenic pressure test, pushing Starship SN4’s propellant tanks all the way to 7.5 bar (~110 psi) at the same time as hydraulic rams simulated the thrust of three Raptor engines at the rocket’s base.

Instead of reinstalling Raptor SN18, SpaceX transported Raptor SN20 to the launch pad and installed it on Starship SN4 on May 10th, less than 24 hours after the prototype passed an orbital-class pressure test.

Aside from installing Raptor SN20, SpaceX teams have spent the last few days adding new COPVs (composite overwrapped pressure vessels) and plumbing to Starship SN4’s exterior – purpose largely unknown. While the new hardware is mostly a mystery, it is known that SpaceX is in the process of preparing SN4 and its new Raptor engine for a third wet dress rehearsal (WDR) and static fire test, necessary to ensure that Raptor SN20 is properly installed and functioning as expected.

Assuming that third static fire is successful, SpaceX’s will prepare Starship SN4 for its first flight, a ~150m (500 ft) hop test that will also be the first intentional flight of any full-scale Starship prototype since the program’s birth. For that hop test, SN4 will need some kind of attitude control system (ACS) thrusters to control its rotation and provide fine trajectory tuning to assist the ship’s lone Raptor engine. This is the likeliest explanation for the new hardware being installed on Starship SN4, as the ship does not currently appear to have ACS thrusters installed.

Starship Troopers
Of course, the first flight of a full-scale Starship prototype will probably be the riskiest test yet for the program and there’s a good chance that SN4 will meet its demise at some point during that flight. Enter Starship SN5.


As of May 12th, Starship SN5’s final two tank sections were stacked, effectively completing the most important half of the rocket (minus one final circumferential ring weld). SN5’s final outfitting of avionics and plumbing is still pending and will take at least a few days to a week or more, but that work can and has been completed after prototypes are transferred by road to the launch pad. Currently, Starship SN4 is occupying SpaceX’s one and only pad test stand, however, meaning that it wouldn’t make much sense to immediately move SN5 to the launch pad – at least until SN4 is done testing.

SN5 will also need a nose section and, perhaps, flaps installed, meaning that the fullship is likely still at least a week or two away from being finished, but that likely wont stop SpaceX from proof testing the rocket’s tanks if or when SN4 makes space at the launch pad.


According to comments made by Elon Musk, SN5 will likely become the first Starship prototype to have three Raptor engines installed and the first to attempt a truly high-altitude flight test if Starship SN4 is met with success in the coming weeks. As absurd as it feels to say, if SN5 completes triple-Raptor testing and a 20 km (~12 mi) flight test without issue, Musk has stated that the next step would be orbital flight tests. Starship SN6’s steel rings, meanwhile, are already being formed and stacked as SN5 nears completion.

https://www.teslarati.com/spacex-starship-fleet-sn5-prototype-progress/

 

[Hamartia Antidote]

https://www.cnbc.com/2020/06/07/elo...x-employees-starship-is-the-top-priority.html
Elon Musk tells SpaceX employees that its Starship rocket is the top priority now

SpaceX launched astronauts for the first time barely a week ago but CEO Elon Musk does not want the company resting on its laurels.

Instead, Musk urged SpaceX employees to accelerate progress on its next-generation Starship rocket “dramatically and immediately,” writing Saturday in a company-wide email seen by CNBC.

“Please consider the top SpaceX priority (apart from anything that could reduce Dragon return risk) to be Starship,” Musk wrote in the email.

SpaceX did not immediately respond to CNBC’s request for comment on Musk’s email.

His space company launched a pair of NASA astronauts on May 30, marking a historic first for SpaceX and a crucial step forward for the U.S. space program. A SpaceX Falcon 9 rocket and Crew Dragon capsule carried the astronauts to orbit and on to the International Space Station. That mission is ongoing, as Musk noted, with the spacecraft set to return the astronauts to Earth in the next couple months.


The Falcon 9 rocket that launched the astronauts is the mainstay of SpaceX’s business, with 85 missions over the past decade. But Starship represents the company’s aim to make obsolete even the cost-saving advances of its Falcon 9 fleet. Its Falcon 9 rockets are partially reusable, as the company often lands the large “booster” stage of the rocket and recovers the rocket’s nosecone. But Musk’s goal is to make Starship fully reusable — envisioning a rocket that is more akin to a commercial airplane, with short turnaround times between flights.

Musk last year unveiled the Starship prototype, built of stainless steel and dwarfing the company’s existing spacecraft. SpaceX is developing Starship with the goal of launching as many as 100 people at a time on missions to the moon and Mars.

SpaceX’s first Starship prototype under construction near Boca Chica, Texas in 2019.
SpaceX

“We need to accelerate Starship progress,” Musk said in Saturday’s email.

Musk’s emphasis on Starship comes nine months after a controversial comment by NASA Administrator Jim Bridenstine, just before SpaceX unveiled the latest prototype. The NASA chief declared his agency wanted “to see the same level of enthusiasm” for SpaceX launching NASA astronauts as there was for the Starship program, saying it was “time to deliver.”


At the time, Musk said that SpaceX “resources are overwhelmingly” focused on finishing development of the Crew Dragon spacecraft. Now, with SpaceX having delivered on the first part of its commitment to fly NASA astronauts, Musk is turning the company’s attention to Starship.

SpaceX has raised nearly $1.7 billion since the beginning of 2019, with its valuation rising to around $36 billion according to CNBC sources. The company has steadily raised funding as its developed three ambitious programs: the Crew Dragon spacecraft, its Starlink internet satellites and the massive Starship rocket.

The Starship program has seen prototypes pass several critical milestones but SpaceX has yet to begin flight testing its most recent design. A previous iteration, known as Starhopper, completed a short launch and landing flight test in August.

Airlift to Texas
SpaceX continues to build up its facility in Boca Chica, an area along the Gulf of Mexico at the most southern part of the U.S. and Mexico border in Texas. Musk noted that he’s often been on site at Boca Chica recently and continues to do so. On Saturday he tweeted an aerial view of the complex, showing its growing array of production tents and rocket manufacturing bays.

In his email, Musk asked SpaceX employees to “consider spending significant time” in Boca Chica to help further accelerate Starship development. SpaceX has about 8,000 employees, most of whom are at the company’s Los Angeles area headquarters or its facilities at Cape Canaveral, Florida or near Austin, Texas. Although SpaceX has some land under lease in the Port of Los Angeles for Starship development, Musk’s email implied that the company is seeking to incentivize employees to move to Texas from California and Florida.

“For those considering moving, we will always offer a dedicated SpaceX aircraft to shuttle people,” Musk wrote.

SpaceX owns and operates at least one private jet, as the company has charged Tesla for use of the aircraft as recently as the first quarter of 2020. But the extraordinary relocation offer underlines how crucial Musk sees the Starship project. The company’s Boca Chica team is already working nearly around the clock but Musk wants more, urging SpaceX employees to help Starship development progress even more quickly.