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Elon Musk’s SpaceX is preparing to launch the latest prototype of its next-generation Starship rocket on Wednesday, in the third high-altitude flight test of the system.
Starship prototype rocket Serial Number 10, or SN10, will aim to launch and fly as high as 10 kilometers, or about 32,800 feet in altitude. The rocket is built of stainless steel, representing the early versions of the rocket that Musk unveiled in 2019.
SpaceX fired the rocket’s engines briefly for a launch attempt at about 3:15 p.m. ET but an unknown issue caused the rocket to abort the attempt and the engines shutdown. SpaceX principal integration engineer John Insprucker said on the company’s webcast that it is evaluating whether there is time to reset the rocket and try another attempt today. The Federal Aviation Administration’s launch window for the SN10 attempt runs until 7:30 p.m. ET.
The company is developing Starship with the goal of launching cargo and people on missions to the moon and Mars.
Starship prototype rocket SN10 stands on the launchpad at the company’s facility in Boca Chica, Texas.
The flight will be similar to the ones SpaceX conducted in December and February, when it test flew prototypes SN8 and SN9, respectively. Both prior rockets completed several development objectives – including testing aerodynamics, shutting down the engines in succession, and flipping to orient for landing –but both prototypes exploded on impact as they attempted to land, unable to slow down enough.
Like SN8 and SN9, the goal of the SN10 flight is not necessarily to reach the maximum altitude, but rather to test several key parts of the Starship system. The Starship prototype stands at about 150 feet tall, or about the size of a 15-story building, and is powered by three Raptor rocket engines. SpaceX will fire all three engines for liftoff and then shut them down one at a time in sequence as it nears the top of the flight’s intended altitude.
SN10 will aim to transfer propellant from the main tanks to the header tanks, and then flip itself for the “belly flop” reentry maneuver so it can control its descent through the air with the rocket’s four flaps. Then, in the final moments of descent, SpaceX will flip return the rocket to a vertical orientation and fire the Raptor engines to slow itself down for a landing attempt.
While SpaceX has yet to land a Starship prototype successfully after a high-altitude flight test, the company has landed previous prototypes after short flights to about 500 feet in altitude.
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