Feed: Slashdot
Feed Link: https://slashdot.org/
---

Title: SpaceX Starship Blasts Off In Ninth Test Flight

Link: https://science.slashdot.org/story/25/05/28/0...

SpaceX's Starship Flight 9 successfully launched and reached space -- marking
the first reuse of a Super Heavy booster -- but both rocket stages were
ultimately lost mid-mission due to a "rapid unscheduled disassembly." SpaceX
CEO Elon Musk said in a statement: "Starship made it to the scheduled ship
engine cutoff, so big improvement over last flight! Leaks caused loss of main
tank pressure during the coast and re-entry phase. Lot of good data to
review." Musk said the next three Starship test launches could lift off every
three to four weeks in the days ahead. Space.com reports: The mission lifted
off from Starbase today at 7:37 p.m. EDT (2337 GMT; 6:37 p.m. local Texas
time), sending the 40-story-tall rocket into the Texas sky atop a pillar of
flame. It was a milestone launch, marking the first-ever reuse of a Super
Heavy booster; this one earned its wings on Flight 7 in January. (SpaceX
swapped out just four of its Raptors after that mission, meaning that 29 of
the engines that flew today were flight-proven.) "Lessons learned from the
first booster refurbishment and subsequent performance in flight will enable
faster turnarounds of future reflights as progress is made towards vehicles
requiring no hands-on maintenance between launches," the company wrote in a
Flight 9 mission preview. The Super Heavy had a somewhat different job to do
today; it conducted a variety of experiments on its way back down to Earth.
For example, the booster performed a controlled rather than randomized return
flip and hit the atmosphere at a different angle. "By increasing the amount
of atmospheric drag on the vehicle, a higher angle of attack can result in a
lower descent speed, which in turn requires less propellant for the initial
landing burn," SpaceX wrote in the mission preview. "Getting real-world data
on how the booster is able to control its flight at this higher angle of
attack will contribute to improved performance on future vehicles, including
the next generation of Super Heavy." These experiments complicated Super
Heavy's flight profile compared to previous missions, making another
"chopsticks" catch at Starbase a tougher proposition. So, rather than risk
damaging the launch tower and other infrastructure, SpaceX decided to bring
the booster back for a "hard splashdown" in the Gulf of Mexico on Flight 9.
That was the plan, anyway; Super Heavy didn't quite make it that far. The
booster broke apart about 6 minutes and 20 seconds into today's flight, just
after beginning its landing burn. "Confirmation that the booster did demise,"
[Dan Huot, of SpaceX's communications team] said during the Flight 9 webcast.
Super Heavy's flight ended "before it was able to get through landing burn,"
he added. Ship, by contrast, improved its performance a bit this time around.
It reached space today on a suborbital trajectory that took it eastward over
the Atlantic Ocean -- the same basic path the vehicle took on the truncated
Flight 7 and Flight 8. But Flight 9 got choppy for Ship after that. The
vehicle was supposed to deploy eight dummy versions of SpaceX's Starlink
satellites about 18.5 minutes after liftoff, which would have been a landmark
first for the Starship program. That didn't happen, however; the payload door
couldn't open fully, so SpaceX abandoned the deployment try. Then, about 30
minutes after launch, Ship started to tumble, which was the result of a leak
in Ship's fuel-tank systems, according to Huot. "A lot of those [tanks] are
used for your attitude control," he said. "And so, at this point, we've
essentially lost our attitude control with Starship." As a result, SpaceX
nixed a plan to relight one of Ship's Raptor engines in space, a test that
was supposed to happen about 38 minutes after launch. And the company gave up
hope of a soft splashdown for the vehicle, instead becoming resigned to a
breakup over the Indian Ocean during Ship's reentry. The company therefore
will not get all the data it wanted about Flight 9. And there was quite a bit
to get; for example, SpaceX removed some of Ship's heat-shield tiles to
stress-test vulnerable areas, and it also tried out several different tile
materials, including one with an active cooling system. But the company plans
to bounce back and try again soon, just as it did after Flight 7 and Flight
8. You can watch a recording of the launch on YouTube.

Read more of this story at Slashdot.

---
VRSS v2.1.180528