Ariane 6 upper stage completes acoustic testing at ESA's Netherlands site

Ariane 6 upper stage completes acoustic testing at ESA's Netherlands site
by Erica Marchand
Paris, France (SPX) Nov 13, 2024

The upper stage of Ariane 6, Europe's latest rocket, has successfully completed its final testing phase at the European Space Research and Technology Centre (ESTEC) in the Netherlands, confirming its readiness for a four-booster variant launch, the most powerful version of Ariane 6.

Five tests at varying acoustic intensities validated the upper stage's capability to withstand the rigorous conditions of a four-booster launch. Conducted by ArianeGroup teams, these tests utilized a model previously involved in hot-fire tests at Germany's DLR test facility in Lampoldshausen from 2022 to 2024.

Rocket launches produce immense sound energy, and the Ariane 6 upper stage was exposed to this simulated environment in the Large European Acoustic Facility (LEAF), Europe's most powerful acoustic testing center at ESA. The LEAF facility replicates the auditory conditions of a rocket launch, ensuring the upper stage can endure the intense sound waves expected during liftoff.

The Ariane 6 rocket is designed to be adaptable, offering configurations with either two or four boosters to meet various mission needs based on payload weight and destination. The rocket's maiden flight, conducted in July 2024 with two boosters, successfully delivered its payload to orbit. The upcoming four-booster configuration, set for 2025, will produce nearly twice the thrust, subjecting the upper stage to 60% more acoustic stress.

Positioned about 34 meters above the rocket engines, the Upper Propulsion Liquid Module (UPLM) of Ariane 6 was specifically engineered for these conditions. During testing, the module, over six meters tall and the heaviest structure evaluated in the LEAF to date, was filled with a mix of water and glycerine to simulate in-flight conditions.

Equipped with 200 sensors, the test model recorded its responses to the acoustic simulations, while black covers mimicked the rocket's intertank structures and acoustic insulation. The LEAF's half-meter-thick walls and secure doors were essential for containing the noise during these tests.

The facility's final test scenes show the massive LEAF chamber with its doors open after the acoustic trials, showcasing the scale and robust design needed to handle Europe's most intense sound tests.