Update:Yesterday (March 9th), Elon Musk shared the reason for the explosion via Twitter. According to Musk, the problem originated with the one Raptor engine used to slow the SN10 down before landing.
“SN10 engine was low on thrust due (probably) to partial helium ingestion from fuel header tank,” he tweeted. “Impact of 10m/s crushed legs & part of skirt. Multiple fixes in work for SN11.“
On March 3rd, 2021, SpaceX conducted a third high-altitude flight test with one of their Starship prototypes (SN10). This time around, the prototype managed to achieve an apogee of 10 km (6.2 mi), a controlled descent relying on nothing but its aerodynamic surfaces (the “belly-flop”), and even managed to land successfully. However, a few minutes after it stuck the landing, the SN10 exploded on the landing pad.
Whereas the SN8 and SN9 explosions were attributed to problems that took place during engine reignition, the cause of the SN10 explosion was not as clear. Thankfully, astrophysicist and Youtube personality Scott Manley (Twitter handle @DJSnM) has offered his take on what might have caused it. Using SpaceX’s footage of the SN10 flight test, he suggests that a slightly-harder-than-intended landing and a fuel tank rupture were responsible.
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!
Another day, another round of testing (and yes, another explosion). Today, on Tuesday, Feb. 2nd, 2021, flight teams at SpaceX’s launch facility near Boca Chica, Texas, conducted a high-altitude test flight with a Starship prototype. Similar to the previous test in December, the SN9 was powered by three Raptor engines, flew to an altitude of 10 km (6.2 mi), then attempted another “belly flop” to test out its fins and aerodynamic surfaces.
As always, the event was broadcast via live stream by SpaceX, NASASpaceFlight, LabPadre, and several other observers. Like the SN8 test flight, SpaceX’s coverage provided multiple vantage points (landing pad, engine compartment, fuselage, aerial drone, etc.) The flight commenced at 2:25:15 P.M. CST (04:25:15 EST; 12:25:15 PST) when the Starship ignited its three engines and began its ascent.