SpaceX’s SN8 spaceship climbs and flies, however fails to land. Effectively, carry the SN9 with you!
SpaceX has finally made the first high-altitude test flight with its prototype Starship! During launch, the eighth iteration of their spacecraft (SN8) flew to an altitude of 12.5 km and performed some fancy maneuvers before returning to their landing site. Unfortunately the landing was a bit hot and the SN8 exploded as soon as it touched down.
Although SpaceX failed to get home in one piece (well, technically, but then exploded), SpaceX validated its spacecraft design for soaring, which is an important step in conducting regular space flights. In addition, the data they have collected from this test and the failed landing are already being used in preparation for the next high-altitude flight test. So this test was really a very important milestone on the way to regular flights to the moon and Mars.
The launch window opened this morning at 7:00 a.m. CST (8:00 a.m. EST; 5:00 a.m. PST) and closed at 5:00 p.m. CST (6:00 p.m. EST; 3:00 p.m. PST). An attempt was made yesterday (Tuesday, December 8th) but scrubbed after a pre-flight engine problem resulted in an automatic shutdown. Today’s launch was originally scheduled to be at 3:00 p.m. CST (1:00 p.m. PST; 4:00 p.m. EST) but was canceled at 2:12 a.m. prior to launch.
Still image of the SpaceX live stream with the three different feeds. Image Credit: SpaceX
Ground teams requested that the countdown be interrupted (the obvious cause being that an aircraft had entered restricted airspace) and then reset the start clock. A new launch was tentatively scheduled for 4:40 p.m. CST, just 20 minutes before today’s launch window closed. The countdown resumed just before 4:00 p.m. CST and the SN8 started at 4:45:26 p.m. CST (2:25:26 p.m. PST; 5:25:26 p.m. EST)!
The launch began without incident when all three Raptor engines ignited and the spaceship slowly lifted off the pad. SpaceXs shared the entire event via live stream (see below), which recorded everything with an outside camera, a downward facing camera on the outside of the spaceship, and a third camera in the “rock” (engine compartment).
Just before 4:42 minutes, the SN8 reached its target altitude of 12.5 km (41,000 feet) and the Raptor engines were shut off. The SN8 rolled in the air for a moment before beginning its descent and tilting its hull towards the ground. This was the much anticipated “belly-flop” maneuver, testing the spacecraft’s maneuvering flaps and aerodynamic surfaces.
The SN8 performs its “belly flop” maneuver. Image Credit: SpaceX
The spaceship then glided through the air for over a minute, making most of the way back to the landing site. The ground teams then reignited the three Raptor engines (6:25 minutes after takeoff), which giggled and fired to swing the tail section quickly around. The last 17 seconds of the test consisted of the SN8 slowing down enough to allow it to land gently.
Unfortunately, immediately after touchdown, the SN8 went up in flames 6:42 minutes after takeoff (at 4:52:08 p.m. CST) and then quickly exploded. With the exception of the external camera, all video feeds were abruptly interrupted and after a few seconds the smoke dissipated to reveal a small pile of dirt and much of the nose cone that was scattered across the pad. The live feed ended with the message:
“Great test, congratulations Starship, steam! SN9 Up Next! ”
Elon Musk took to Twitter about 10 minutes after the flight ended to put the test (and its fiery finale) into context. First of all, he praised the successes they had achieved with this last run of the spaceship.[s]Successful ascent, conversion to collection tanks and precise flap control to the landing point. ”
The still image of the SN8 explodes immediately after touching down on the landing pad. Image Credit: SpaceX
He also explained the reason why SN8 exploded immediately after reaching the landing site:
“The pressure in the fuel tank was low during landing, resulting in a high touchdown speed and RUD, but we have all the data we needed! Congratulations SpaceX Team Hell yeah !! ”
For the recording, RUD stands for “Rapid Unscheduled Disassembly”, a term in aerospace engineering that essentially means code for “Kaboom!” Is. That said, Musk is certainly right, and there are many reasons SpaceX is feeling solemn right now. With the exception that the SN8 arrived too quickly and burned on the landing pad, it managed to do everything that was intended for this flight test.
It peaked at 12.5 km, successfully gliding through the atmosphere with nothing but its fins and surfaces, and managed to reignite its engine just in time to turn around and land. As for the landing portion, Musk and his engineers now have the data they need to make sure the next flight test has more time to slow down.
Given SpaceX’s highly iterative rapid prototyping approach, these errors can be instantly translated into success. The SN9 is almost completely stacked and processed and at this point is just waiting for the integration of its nosecone. Barring unforeseen delays, it could be ready to do a similar hop test in a few weeks.
At this point it is impossible to tell if the SN9’s hop test will have a similar target altitude of 12.5 km or if it will try to reach a higher altitude. Originally, the altitude test was supposed to peak at 20 km (~ 12.5 mi) above sea level. However, this value was reduced as the SN8 approached the attempt – first to 15 km (9.5 mi; 50,000 ft) and then to 12.5 km.
However, SpaceX is sure to shift the envelope as they near an orbital flight test in the near future. A Starship prototype will try to reach a height of 200 km with six Raptor engines. Musk also stated last week that he was “very confident” that the spacecraft would complete a crewed mission to Mars by 2026. While this means a two year delay, it’s fair to say he’s still on a tight schedule!
In the meantime, several more prototypes (SN10 to SN15) are in various stages of manufacture and assembly, and construction of the first Super Heavy prototype (BN1) is in full swing. So expect lots of news from Boca Chica in the months and years to come! Also watch the video of the start (the start starts at 1h48m).
Further reading: SpaceX