Rollout of Aurora test platform ALEDA

Polaris Spacecraft announced that rollout and initial roll tests were conducted March 3. The first flights are then expected to be conducted in the coming weeks. ALEDA is a 3.5-meter long scale model of the Aurora spaceplane. It was built to already validate flight characteristics during takeoff, cruise and landing. It will also be used to verify aerodynamics and flight control characteristics. This is important because the Aurora spaceplane is designed to be aerodynamically unstable to maximize its performance.

Aerodynamic instability - tendency to crash

This characteristic, known in aviation as relaxed or negative stability, makes it necessary to permanently control the aircraft's attitude. Aircraft with such a design have a tendency to change pitch and roll angles spontaneously. This makes them fundamentally different from aircraft with a stable design, which return to their initial orientation after a pitch or roll disturbance. Aerodynamically unstable aircraft, on the other hand, pitch or roll at an ever-increasing rate in the direction of the disturbance when disturbed. Compensating controls must therefore be so fast that they cannot be taken over by humans. The use of a flight control system is thus indispensable.

Reusability of the overall system

The ALEDA scale model will also be used to verify aerodynamics and flight control characteristics when carrying an externally mounted, reusable upper stage. Although the Aurora spacecraft will initially carry conventional upper stages and payloads in an internal payload bay. Aurora's primary mission is specified as launching satellites of 800 - 1,000 kg. However, optional use of winged reusable upper stages is also of interest for special missions. According to Polaris Raumflugzeuge, this allows 100% reusability of the entire system. In addition, mission scenarios serving defense and/or hypersonic flight are also conceivable.

via Polaris Raumflugzeuge