Musk outlines major upgrades for Starship rocket
Spaceflight Now June 25, 2023 William Harwood
SpaceX will need another six weeks or so to finish implementing hundreds of changes to its Super Heavy-Starship rocket and the gargantuan booster’s Texas launch pad before it will be ready for a second attempt to reach orbit, company founder Elon Musk said Saturday.
That’s assuming Federal Aviation Administration clearance to fly in the wake of the Super Heavy’s dramatic maiden launch April 20 in which the rocket blew itself up after multiple engine failures and the Starship upper stage’s failure to separate from the first stage booster.
In a Twitter Spaces discussion with author Ashlee Vance, Musk said SpaceX is implementing “well over a thousand” changes,” and “I think the probability of this next flight working, getting to orbit, is much higher than the last one. Maybe it’s like 60 percent. It depends on how well we do at stage separation.”
The reusable Super Heavy first stage is equipped with 33 methane-powered Raptor engines while the Starship second stage features six. The original design called for the Super Heavy’s engines to shut down after boosting the Starship out of the lower atmosphere. The Starship then would separate and ignite its own engines to continue on to orbit.
During the rocket’s maiden flight, a half-dozen engines shut down or never started and the Starship never separated from the Super Heavy first stage.
After reaching an altitude of just 24 miles or so, the entire vehicle began tumbling, falling about six miles before its self-destruct system activated, blowing the rocket apart. The self-destruct system took longer to respond than expected.
For its second flight, Musk said the stage separation system has been modified, a “late breaking change that’s really quite significant.”
The Starship’s engines will begin firing before all of the Super Heavy engines have shut down. This so-called “hot staging” technique has been used for years in Russian rockets. Musk said it would improve the performance of the Super Heavy-Starship by reducing the velocity lost between first stage engine shutdown and ignition of the upper stage engines.
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