From Liftoff to Relight: IFT-6 Pushes Starship Closer to Orbit

On November 19, 2024, SpaceX conducted its sixth integrated flight test (IFT-6) of the Starship launch system from Starbase in Boca Chica, Texas. The mission aimed to further validate the vehicle’s capabilities, building upon the achievements of previous tests. 

Launch and Ascent 

At 4:00 p.m. CST, the Super Heavy booster, designated Booster 13, ignited its 33 Raptor engines, propelling the Starship system off the launch pad. The vehicle successfully navigated through Max Q, the phase of maximum aerodynamic pressure, demonstrating structural integrity under significant stress. 

Stage Separation and Upper Stage Operations 

Approximately two minutes and 39 seconds into the flight, the Starship upper stage, known as Ship 31, executed a hot-staging maneuver. This process involved igniting its engines before complete separation from the booster, enhancing efficiency and performance. Ship 31 continued its ascent, reaching the intended suborbital trajectory. Notably, the upper stage performed an in-space relight of a single Raptor engine, a critical test for future orbital missions requiring precise engine restarts in space. 

Booster Recovery Attempt 

Post-separation, Booster 13 was programmed to execute a boost-back burn, returning to the launch site for a catch using the launch tower’s mechanical arms, colloquially known as “chopsticks.” However, during the descent, an issue with the launch tower’s systems prompted mission control to abort the catch attempt.  

“During this phase, automated health checks of critical hardware on the launch and catch tower triggered an abort of the catch attempt. The booster then executed a pre-planned divert maneuver, performing a landing burn and soft splashdown in the Gulf of Mexico.”  (– SpaceX – Launches) 

The abort of the boost catch should not be looked at as a failure. Instead, it was a remarkable success that in midflight this 23-story tall rocket gracefully changed its flight path and performed a soft water landing safety 24 miles away from harming and body or any property. The successful demonstration of this ability to recognize an issue and change course midflight is a remarkable engineering and programing accomplishment.

Mission Outcomes 

Despite the aborted booster catch, IFT-6 achieved several significant milestones: 

• Successful Liftoff and Ascent: The vehicle demonstrated reliable performance during launch and ascent phases. 

• Effective Hot-Staging: The upper stage’s hot-staging maneuver was executed as planned, indicating progress in stage separation techniques. 

• In-Space Engine Relight: The upper stage’s successful engine relight in space is a crucial step toward enabling deorbit burns for future orbital missions. 

The decision to abort the booster catch underscores SpaceX’s commitment to safety and operational prudence. By opting for a controlled splashdown, the company mitigated potential risks associated with the catch mechanism’s malfunction. 

Overall, IFT-6 provided valuable data and insights, contributing to the iterative development of the Starship system. Each test, regardless of outcome, offers lessons that inform future designs and operational strategies, bringing SpaceX closer to its goal of creating a fully reusable launch vehicle.