Starship Completes its Fifth Test Flight, Demonstrating Booster Catch

Today, SpaceX’s Starship program achieved one major step forward by successfully catching a Super Heavy booster using the launch tower. Additionally, the Starship spacecraft completed a water landing in the Indian Ocean. This milestone had already been achieved on the last flight, but today SpaceX demonstrated improvements in integrity during reentry.

Liftoff of Starship! pic.twitter.com/WyNRN1fLbd
— SpaceX (@SpaceX) October 13, 2024

^{Launch of Starhip IFT-5. Credits: SpaceX via Twitter/X}

Starship thus continues moving forward toward orbital flights, and eventually operational missions. These include fulfilling the Human Landing System contract for NASA’s Artemis program, launching Starlink V2 satellites, and ultimately making life multiplanetary.

Liftoff

Starhip’s Integrated Flight Test 5 (IFT-5) lifted off on October 13, 2024, at 12:25 UTC from Starbase Orbital Launch Mount A. All 33 Raptor engines on Super Heavy ignited successfully, lifting the Booster 12 and Ship 30 stack in the air. The rocket immediately pitched down to perform a pad avoidance maneuver, ensuring it would not fall back on the OLM were it to fail catastrophically.

One minute into the flight, the stack experienced peak aerodynamic loads. At T +2:34 the complex hot-staging sequence began. The two outer rings of engines on Super Heavy shut down in groups, a measure taken to limit stress on the fuel lines. Then the engines on the Starship spacecraft ignited, and at T +2:41 the two vehicles separated.

Starship hot-staging separation pic.twitter.com/6tRw2OjtMm
— SpaceX (@SpaceX) October 13, 2024

^{Starship performs the hot staging maneuver. Credits: SpaceX via Twitter/X}

While the Starship spacecraft proceeded to orbital velocities, Super Heavy performed its boostback burn. The 10 Raptors on the inner ring relit, joining the 3 central ones that had never stopped firing. For approximately 45 seconds, the booster burned to get on a trajectory headed for Starbase. 15 seconds later, the three center engines also shut down. During the burn Booster 12 skimmed the edge of space, reaching an apogee of 96 km.

Catch

After approximately three minutes of coasting, at T +6:30 Super Heavy relit its innermost 13 engines, beginning the landing burn. 7 seconds later 10 engines shut down, leaving only 3 Raptors on to perform the precise maneuvers needed to land.

The booster then moved towards the launch tower, leaving its trajectory that would have led to a slight miss were the engines unable to relight correctly. As Booster 12 came down towards the tower, it swung away from it to cancel lateral velocity. Finally, Super Heavy stopped mid-air in a hover, giving the chopsticks time to close. At T +6:59 all engines shut down, leaving Booster 12 hanging from Mechazilla as planned. The booster was lowered on the OLM approximately five hours after the flight, with the Quuck Disconnect being then reattached.

Mechazilla has caught the Super Heavy booster! pic.twitter.com/6R5YatSVJX
— SpaceX (@SpaceX) October 13, 2024

^{Booster 12 is caught by Mechazilla. Credits: SpaceX via Twitter/X}

The maneuver was not entirely without flaws, however. As the 10 inner ring engines shut down, large flames billowed from the base of Super Heavy. After catch, a small fire kept burning near the Quick Disconnect location of the booster. One of the aerodynamic chines also had a portion of its skin stripped, leaving the structure underneath visible. However, all Raptor engines seemed to perform as expected, with no engine losses reported.

Reentry

Shortly after booster catch, the Starship spacecraft shut down its engines. At T + 6:59 the outboard vacuum engines shut down, while the center sea-level Raptors came offline at T +7:27. Starship achieved an apogee of 212 km. As planned, the spacecraft did not achieve a stable Earth orbit, avoiding the risk of leaving an enormous piece of debris stranded in orbit. The onboard cameras showed signs of some tile damage.

*Ship 30 in a suborbital trajectory, showing some sign of tile damage. Credits: SpaceX via Twitter/X*

After a 40-minute coast phase, Starhip began reentry. Plasma first appeared approximately 45 minutes into the flight, at an altitude of 102 km. By this time the vehicle had oriented itself to present its thermally protected belly to the airstream. Both flaps were already moving to control the vehicle, albeit very slowly.

Ship 30 reenters through Earth's atmosphere, with plasma engulfing the vehicle's belly and some burn-through occuring at a flap's base. Credits: SpaceX via Twitter/X — *Ship 30 reenters through Earth’s atmosphere, with plasma engulfing the vehicle’s belly and some burn-through occurring at a flap’s base. Credits: SpaceX via Twitter/X*

Temperature and heat flow then began increasing, putting the thermal protection system to the test. At T+57 minutes one of the rear flaps appeared to show some limited signs of damage, with the plasma being visible through a fissure in the skin. A minute later, the other rear flap showed a similar phenomenon at its hinge. At this point, Starship was still 50 km high and moving at 3.7 km/s.

Splashdown

By T +63 minutes, Starship was 15 km above the Indian Ocean, with the flaps moving faster than earlier to maintain a belly-first attitude. At T +1:05:23 the three sea-level Raptors relit. Starship executed its characteristic belly-flop maneuver, coming to a water landing 22 seconds later.

Ship 30 as it approaches the surface of the Indian Ocean during it's belly-flop maeuver. Credits: SpaceX via Twitter/X — *Ship 30 as it approaches the surface of the Indian Ocean during its belly-flop maneuver. Credits: SpaceX via Twitter/X*

Subsequently, the vehicle tipped over and detonated, having by then completed its mission. The explosion was recorded by a pre-positioned buoy. The fact that the floating platform was able to record the event is a testament to the landing precision achieved by Starship on this flight.

Looking forward

Like all previous Starship flights, this launch represented an improvement upon the previous mission. While SpaceX has yet to release all the details, it is clear that successfully catching the Super Heavy booster on the first attempt is a major achievement for the program. In the future, SpaceX will likely have to address the damage encountered by Booster 12 during its landing. The burn-through issues the flaps encountered on reentry will probably have to be taken care of as well. However, the FAA won’t be requiring an investigation, as it has stated that “All flight events for both the Starship vehicle and the Super Heavy booster occurred within the scope of planned and authorized activities.”

*Ship 30 tips over and explodes after touchdown, as filmed by a buoy pre-deployed at the splashdown site. Credits: SpaceX via Twitter/X*

Having demonstrated the most important capabilities of Starship in its launch and landing phases, the next major milestone will be to relight Raptors in space. Such an achievement would pave the way for proper orbital flights. We may also see a repeat of this flight with the same exact profile, as changes to the FAA licensing procedure would allow that to happen rather rapidly. That is if SpaceX decides to move in that direction, of course.

^{*Cover image credits: SpaceX}