Scenes from testing the Aquila engine, designed, built and tested by Isar Aerospace at their engine test site in Esrange, Sweden.

Isar Aerospace finished engine hotfire testing for its Aquila engines in October 2023 by firing an Aquila engine for 260 seconds multiple times – more than it needs to fire for a flight. The test exceeded expectations by firing one of the engines six separate times without refurbishment.

Munich-based Isar Aerospace was supported by ESA’s Business Incubation Centre and previous Boost! contracts in 2020 and 2021. Its Spectrum rocket will be 28 m tall, 2 m in diameter and its ten engines will launch payloads in two-stages with of up to 1000 kg to low Earth orbit, or 700 kg to a sun synchronous orbit.