The European Space Agency (ESA) has successfully completed the final wet dress rehearsal for the Ariane 6 rocket, marking a significant milestone before its inaugural launch scheduled for July 9.
This comprehensive test involved fueling the rocket and executing a countdown that stopped just before engine ignition, ensuring all systems and procedures are ready for the actual launch.
Ariane 6 Rocket Undergoes Rigorous Testing at Europe’s Spaceport
On June 20, 2024, the Ariane 6 rocket underwent its final wet dress rehearsal at Europe’s Spaceport in French Guiana. This rehearsal was a critical step in the launch preparations, allowing the team to fine-tune the complex operations required up until liftoff. Guy Pilchen, Ariane 6 launcher project manager at ESA, emphasized the importance of this test: "The wet dress rehearsal is the very final milestone before launch, allowing teams to fine-tune the delicate operations required up until liftoff, using the real rocket’s actual flight hardware and software for the first time."
The test began with the rollback of the 90-meter tall Ariane 6 mobile gantry, a massive structure that provides access to the rocket during pre-launch preparations. Rolling it back 120 meters from the launch pad allowed the rocket to stand free for the first time.
Following this, technicians pumped 180 tonnes of propellant – liquid oxygen (cooled to -180°C) and liquid hydrogen (cooled to -230°C) – into the rocket. This process, taking about 3.5 hours, started with the slow cooling of pipes, valves, tanks, and engines from the tropical temperatures of French Guiana to the super-chilled temperatures of the cryogenic fuels. Any air or moisture was flushed out using nitrogen to prevent blockages from freezing.
Once the tanks were full, teams had to continually top them up as the liquid fuels gradually boiled away in the Sun, ensuring the rocket remained properly fueled and ready for the next stages. The rehearsal included a complete countdown sequence that stopped just before engine ignition. This simulated launch process is critical for verifying the synchronization and readiness of all systems, from ground control software to the rocket's onboard systems.
Meticulous Countdown and Final Checks
The countdown process, which took the rocket through every step up to just before engine ignition, was meticulously executed. ESA Director General Josef Aschbacher noted, "The preparations towards the inaugural flight are really, really progressing well." He added that there were no major issues delaying the launch, indicating a smooth transition towards the final launch phase.
This wet dress rehearsal not only verified the readiness of the rocket and its systems but also ensured the launch team could handle the operations effectively. Data from the rehearsal is being analyzed, with results expected on June 26, which will confirm the final launch date.
Addressing the European Launcher Crisis
The successful rehearsal of Ariane 6 is crucial for ESA's efforts to resolve the "launcher crisis" that has temporarily deprived Europe of independent access to space. The crisis was exacerbated by delays in the development of Ariane 6, issues with the Vega C rocket, and the loss of access to the Soyuz rocket following geopolitical tensions.
Aschbacher highlighted the importance of Ariane 6 in restoring Europe's capability: "Ariane 6 was designed and developed to secure Europe’s independent access to space. With the first launch of this new heavy-lift rocket, Europe is back in space."
Moving Forward with Confidence
The wet dress rehearsal is a testament to the dedication and precision of the teams involved. "The rocket, the launch pad and teams from ESA, CNES and ArianeGroup, all put in a great performance, and everything went smoothly – I couldn’t be prouder," said Pier Domenico Resta from ESA. This success paves the way for Ariane 6’s inaugural flight, which carries significant payloads from various European entities, including NASA and ArianeGroup.
The payloads for this mission include a diverse array of experiments, satellites, and technology demonstrations that showcase the rocket's versatility and importance for future space missions. From Earth observation to testing wildlife tracking technologies, Ariane 6's first flight represents a major leap forward in European space capabilities.