The newest spaceship prototype, the SN11, explodes in midair and rains particles on the launch web site
Space exploration sure is difficult, isn’t it? Fortunately, it’s an iterative process with engineers testing and testing and retesting to fix any errors in advance. At least we remember when the prototype “Kaboom!” The SN11 is now the fourth Starship prototype to successfully perform a flight test and then explode while attempting to land (or shortly afterwards).
This was SpaceX’s fourth high-altitude flight test, in which a three-engine Starship prototype flew to an altitude of 10 km, performed a “belly flop” maneuver, and then attempted a soft landing. As always, the purpose was to test the spacecraft’s ability to soar, maneuver in the atmosphere, switch from its main to its collection tanks, then reignite its engines and realign itself to touch down on a landing pad.
Testing began at 8:00:05 a.m. CDT (6:00 a.m. PDT; 9:00 a.m. EDT) on the morning of March 30, when the SN11 fired all three Raptor engines and launched the Boca Chica Launch Facility from the landing pad . Live coverage was provided by SpaceX (video below) as well as NASASpaceflight, LabPadre, and other regular observers at the facility.
As you can see from the footage, conditions were extremely foggy and the prototype wasn’t always visible to cameras. However, SpaceX’s on-board cameras captured the ascent and descent phases with both the exterior and engine compartment cameras. The SN11 peaked 10 km without incident, then shut off its three engines and realigned itself to begin the descent.
Again, this was successfully carried out and reaffirmed the spaceship’s ability to control its descent using only its aerodynamic surfaces – namely, its two forward and two aft mounted flaps. Due to the thick fog, the ground-based cameras were unable to take a clear picture of the spaceship during the ascent and descent phases. For a few minutes, only SpaceX’s onboard cameras were able to provide coverage, but these were turned on and off several times
5 minutes and 48 seconds after the flight began, the ground teams began reigniting the Raptor engines to realign the spaceship. However, the engine compartment camera suddenly stopped transmitting a second later. At 8:06:06 a.m. local time, the ground cameras recorded the unmistakable sound of an explosion. Almost a minute later, debris was discovered and heard falling around the landing site.
Some of the debris even landed near the location of the ground cameras, but no injuries were reported. From the last few seconds of footage captured by the SpaceX engine bay camera, it was clear that at least the Raptor engine had managed to reignite. However, the prototype exploded before it could touch down, exploding in mid-air, throwing debris around the facility.
The ground teams immediately began searching the data to determine the cause. Elon Musk took to Twitter shortly after the explosion to share her preliminary findings:
“It looks like Motor 2 was having problems climbing and did not reach pressure in the operating chamber during landing, but in theory it was not needed. Shortly after the landing took off, something significant happened. Should know what it was when we can examine the parts later today. “
In all three previous attempts, the spacecraft exploded either during the landing (SN8 and SN9) or shortly after (SN10). In the case of SN8, the prototype managed to realign itself seconds before landing, but it encountered a pressure problem with its collection tank. This resulted in it becoming too heavy, which resulted in a Rapid Unscheduled Disassembly (RUD), which is an aerospace engineer explosion.
In the case of SN9, the prototype passed over during the reorientation and landed on its side, resulting in another RUD. However, the SN10 RUD appeared to be due to a malfunction in the landing legs, half of which was improperly deployed. This caused the SN10 to land harder on one side, causing structural damage to its internal tanks as well as the fuel lines on the landing pad.
The tanks burst a moment later, spat out excess propellant, and launched the prototype into the air. This propellant was ignited by the pre-existing fire and caused an explosion that gave the SN10 an extra boost. This time it looks like there was a problem during the Raptor re-ignition, possibly caused by a cracked fuel line or something that occurred when the mission controllers switched over to the collection tanks.
We will see. Meanwhile, Musk posted some follow-up tweets exchanging information about what kind of Starship tests are ahead of him. This included the next prototype (SN15) and future iterations (like the SN20) that will have the benefit of updated designs:
“The SN15 will roll to the launch pad in a few days. It has hundreds of design improvements in terms of structure, avionics / software, and engine. Hopefully one of these improvements will cover this problem. If not, the upgrade will take a few days longer.
“The next major technology revision is with the SN20. These ships will be orbitable with a heat shield and a step separation system. The probability of success in advancement is high. However, SN20 + vehicles will likely take a lot of flight attempts to survive the Mach 25 entry heating and land intact. “
As always, it goes on and on! In accordance with SpaceX’s rapid prototyping process, the data from this flight will be incorporated into future designs to minimize the risk of failure. On March 18, Musk tweeted a picture showing the first fully assembled Super Heavy Booster in his hangar in Boca Chica. In the near future, SpaceX is also planning high altitude test flights with this and other super heavy prototypes.
Meanwhile, the Boca Chica cleanup crews have cut their work out for them. Much debris needs to be removed and a lot of repairs to be done. You are the real heroes here!
Further reading: SpaceX