Isar Spectrum reaches orbit on second flight with LOX-propane propulsion

(SpaceEnergy) Isar Aerospace’s Spectrum launcher has reached orbit on its second flight, flight-validating the German aerospace company’s liquid-oxygen/propane Aquila propulsion system through staging, second-stage ignition and orbital insertion.

The Onward and Upward qualification mission lifted off from Isar Aerospace’s dedicated launch complex at Andøya Space in Norway at 22:12 CEST on 5 September and successfully deployed its payloads after orbital circularisation.

Isar said Spectrum passed maximum dynamic pressure, completed main-engine cut-off and stage separation, ignited its second stage as planned, crossed the 100km Kármán line and jettisoned its payload fairing before reaching orbital velocity.

Spectrum uses nine 75kN Aquila engines on its first stage and one 95kN vacuum-optimised Aquila on its second stage. The gas-generator-cycle engines burn liquid oxygen and liquid propane and use in-house-developed turbopumps; the upper-stage engine supports multiple ignitions.

The company said vehicles three through seven are already in production. Its new 40,000m² manufacturing facility is intended eventually to support production of up to 40 launch vehicles annually.

Chief executive and co-founder Daniel Metzler said Isar would now focus on “rapidly scaling launch vehicle production” and delivering its order pipeline.