Mar. 2, 2016

The largest sound horn feeding into ESA’s Large European Acoustic Facility – seen here during its installation in 1990 – which is used to subject satellites to a noise level equivalent to a rocket launch.
LEAF is an integral part of ESA’s ESTEC test centre in Noordwijk, the Netherlands, a collection of spaceflight simulation facilities under a single roof. One wall of the chamber – which stands 11 m wide, 9 m deep and 16.4 m high – is embedded with a set of enormous sound horns. Nitrogen shot through the horns can produce a range of noise up to more than 154 decibels, like standing close to multiple jets taking off.

As a safety feature, LEAF can operate only once all the doors are closed. Steel-reinforced concrete walls safely contain its noise, coated with epoxy resin to reflect noise to produce auniform sound field within the chamber. The chamber itself is supported on rubber bearing pads to isolate it from its surroundings.