Tag: Superheavy

According to a tweet put out by Elon Musk on January 8, 2023, SpaceX is now targeting late February/March for 1st orbital launch of the 24th prototype of Starship and the seventh prototype of Superheavy.

The testing in 2022 has not gone as smoothly as hoped, and is the reason no launch occurred last year:

Super Heavy B7 first left SpaceX’s Starbase factory in March 2022 and has been in a continuous flux of testing, repairs, upgrades, and more testing in the nine months since. The 69-meter-tall (~225 ft), 9-meter-wide (~30 ft) steel rocket was severely damaged at least twice in April and July, requiring weeks of substantial repairs. But neither instance permanently crippled the Starship booster, and Booster 7 testing has been cautious but largely successful since the rocket’s last close call.

Following its return to the OLS [orbital launch site] in early August, Super Heavy B7 has completed six static fire tests of anywhere from one to fourteen of its 33 Raptor engines. It has almost certainly dethroned Falcon Heavy to become the most powerful SpaceX rocket ever tested. And on January 8th, 2023, SpaceX rolled the rocket back to Starbase’s orbital launch site for the seventh time. According to statements made by CEO Elon Musk and a presentation from a NASA official, the last major standalone test between Booster 7 and flight readiness is a full 33-engine static fire. Together, B7’s 33 Raptor 2 engines could produce up to 7600 tons (16.7 million lbf) of thrust at sea level, likely making Starship the most powerful rocket stage in the history of spaceflight.

I had read speculation earlier that it was impossible for SpaceX to do a full 33-engine static fire test because the OLS could not hold the rocket down. That now appears to be incorrect.

Musk’s tweet and proposed schedule should also not be taken with great seriousness. He routinely sets ambitious targets merely to keep the pace fast, even if those targets are not met.

Link here.

While work appears to be proceeding aggressively, it increasingly looks like no orbital launch will occur before the end of this year. SpaceX engineers appear to be preparing two different Superheavy prototypes, #7 and #9, but both are still undergoing modifications based on recent engine tests. In addition, modifications to Starship prototype #24 continue.

SpaceX’s seventh prototype of its Superheavy first stage booster — intended to launch its Starship orbital craft on the first orbital flight — successfully completed a 10-second static fire test of 14 of its 33 engines yesterday.

I have embedded video of the test below the fold. It shows the burn repeatedly from different angles. It appears the engine test went exactly as planned, with no subsequent fires near the launch pad.

According to the article at the link, this test fire, even with only 14 engines, made this Superheavy booster the most powerful rocket on Earth, at least until tonight when NASA’s SLS launches. Once this booster fires all of its 33 Raptor-2 engines however it will then exceed SLS in power. That it hasn’t launched however makes this claim a little overstated.

Regardless, SpaceX continues to move quite smoothly towards that first orbital launch of Starship, which the company hopes to do before the end of the year.
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Starship about to be stacked on Superheavy, using
the launch tower’s chopstick arms. Click for full image.

For the first time in six months SpaceX engineers have stacked Starship prototype #24 on top of Superheavy prototype #7, with the intention of running a dress rehearsal countdown and a full static fire test of Superheavy’s 33 engines, all in preparation for the first orbital test flight before the end of this year.

According to CEO Elon Musk, Booster 7 and Ship 24 will attempt Starship’s first full-stack wet dress rehearsal (WDR) once all is in order. The prototypes will be simultaneously loaded with around 5000 tons (~11M lb) of liquid oxygen and methane propellant and then run through a launch countdown. Diverging just before ignition and liftoff, a WDR is meant to be more or less identical to a launch attempt.

…If the wet dress rehearsal goes to plan, SpaceX will then attempt to simultaneously ignite all 33 of the Raptor engines installed on Super Heavy B7, almost certainly making it the most powerful liquid rocket ever tested. Even if all 33 engines never reach more than 60% of their maximum thrust of 230 tons (~510,000 lbf), they will likely break the Soviet N-1 rocket’s record of 4500 tons of thrust (~10M lbf) at sea level. It would also be the most rocket engines ever simultaneously ignited on one vehicle. SpaceX will be pushing the envelope by several measures, and success is far from guaranteed.

Depending on the results of these tests, the stacked rocket will either require further modifications, or could even proceed directly to launch.

We are thus seeing a true race between SpaceX’s privately developed and funded rocket and NASA’s government developed and funded SLS rocket. Which will launch first? Right now the race is neck-and-neck, though that is deceiving since SpaceX began development twelve years after NASA started work on SLS. Even if SLS launches first, SpaceX will have clearly shown that private enterprise does things faster (7 years vs 18 years) and for far less money (about $9 billion vs $46 billion).

According to a tweet yesterday by Elon Musk, SpaceX engineers will likely have the first orbital prototypes of Starship and Superheavy ready for the orbital attempt either late in October, or by November. His full tweet:

Late next month maybe, but November seems highly likely. We will have two boosters & ships ready for orbital flight by then, with full stack production at roughly one every two months. [emphasis mine]

The highlighted words are the most significant. SpaceX is not building one rocket for test, like NASA has done with SLS. It is building an assembly line of test rockets, so that it can do a fast series of test launches plus upgrades, leading to quick and reliable operations. Should any one rocket launch fail, the company will speedily move on to the next, with little or no delay.

Should SLS fail in its first test launch sometime in the next month, NASA has no back-up. The entire program will be shattered, with no easy way to recover.

Capitalism in space: SpaceX today successfully did a static fire engine test of seven engines on its Superheavy prototype #7, intended to be the lower stage of the first Superheavy/Starship orbital test.

The link takes you to the full live stream. Below I have cued that live stream to just before the test occurred. Everything seems to go as planned, with no obvious anomalies.

SpaceX continues to be moving closer and closer to that first orbital flight.
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Link here. The article not only outlines the test program leading to the first launch of prototypes Starship #24 and Superheavy #7, it describes the status of later prototypes, as well as the construction of SpaceX’s Starship launch site in Florida. Key quote:

Booster 7’s gradual approach to static fire testing will allow the teams to fix issues as they test and fully mature procedures and software ahead of the long-awaited orbital flight of Starship. Should this gradual testing go without a hitch, it could culminate in one or perhaps even two 33-engine static fire tests of Booster 7 on the OLM [orbital launch mount].

Once this testing is completed and any issues found fixed, it’ll be cleared to proceed into another phase of testing: Ship 24 will then be stacked on top of Booster 7 for combined tests. This could include launch countdown simulations, an eventual full-up countdown, and a 33-engine static fire test.

SpaceX hopes to complete this by mid-next month and clear both vehicles for launch shortly after. However, as we’ve seen in the past few weeks, any issues encountered during this intense test campaign could well mean a slip to later into the year and, perhaps, into next year.