They say, “third time’s the charm.” This was largely the case today as SpaceX made their third attempt at a high altitude flight test at their launch facility in Boca Chica, Texas. Like the previous two attempts, this flight saw a Starship prototype (SN10) with three Raptor engines fly to an altitude of 10 km (6.2 mi), conduct a “belly-flop” descent maneuver, and then return to the launch facility.
As with the previous high-altitude tests, the SN10 successfully launched, reached its apogee, and validated the control fins and aerodynamic surfaces. But unlike the previous tests, the SN10 was able to slow down enough and keep itself upright so it could make a soft landing. While the prototype exploded a few minutes after landing (apparently from a methane leak) the flight was a complete success!
In the month that passed since the previous flight, ground crews at the SpaceX South Texas Launch Site near Boca Chica had been prepping for their third attempt at a high-altitude flight. After much anticipation, March 3rd was selected as the earliest date for a launch attempt. Initially, Elon Musk and the Boca Chica crews were hoping to launch at 09:00 AM CST (07:00 A.M. PST; 10:00 A.M. EST) but the flight was aborted.
The abort occurred almost immediately after the engines ignited when the automated safety systems kicked in. Musk took to Twitter shortly thereafter to explain why this had happened, tweeting, “Launch abort on slightly conservative high thrust limit. Increasing thrust limit & recycling propellant for another flight attempt today.”
After a few hours of prepping, they made a second launch attempt at around 05:14:45 P.M. CST (03:14:45 P.M. PST, 06:14:45 P.M. EST). The flight began with the SN10 igniting all three of its Raptor engines and lifting off smoothly. The ascent went off without a hitch and was broadcast live by SpaceX, NASA Spaceflight, and others from multiple perspectives (exterior, interior, fuselage, and drone).
About 2 minutes and 13 seconds into the flight, one of the Raptor engines shut down and the other two began to noticeably gimbal – designed to test their thrust-vectoring capabilities. The second cut out 3m15s into the flight and at 3m45s, the prototype reached its apogee of 10 km (6.2 mi), at which point the ground crews switched it over to its header tank.
At 4m19s, the last Raptor engine cut out and the prototype commenced its “belly-flop” maneuver. After descending for about a minute and a half using only its maneuvering surfaces, two of the Raptor engines reignited at 5m45s and the prototype flipped its end around to hover to the ground. Perhaps proving that the third time’s the charm, the SN10 prototype then managed to bring it in for a soft landing!
Unfortunately, things didn’t end there. At 14m27s after launch, the prototype exploded suddenly on the landing pad, apparently as a result of a methane leak. While this indicates that the prototype still has some bugs that need to be worked out before orbital flights can be made, the test was still a complete success. Like the previous tests, the SN10 flight validated the ascent, descent, and maneuvering elements of the systems.
This time, it also validated the spacecraft’s ability to make a soft landing, which relies on several of the Starship’s system. As the company explained in a pre-flight statement:
“A controlled aerodynamic descent with body flaps and vertical landing capability, combined with in-space refilling, are critical to landing Starship at destinations across the solar system where prepared surfaces or runways do not exist, and returning to Earth. This capability will enable a fully reusable transportation system designed to carry both crew and cargo on long-duration, interplanetary flights and help humanity return to the Moon, and travel to Mars and beyond.”
This latest launch comes roughly four weeks after the last (Feb. 2nd), which came a little over five weeks after the first one (Dec. 23rd). At this rate, SpaceX is achieving a good launch cadence, which is essential to success in spaceflight. The ability to turn things around quickly, learning from failures and building on successes, is also in keeping with SpaceX’s rapid prototyping and “testing to failure” approach.
As of today, they are one step closer to achieving Musk’s long-term vision of regular, affordable space travel to orbit, the Moon, and Mars!
Further Reading: SpaceX