Building and operating scaled spaceplane demonstrators is a key for rapid project progress, technology validation and risk reduction. POLARIS follows this approach with a series of five demonstrators of increasing size, mass and complexity. These five demonstrators are complemented by additional auxiliary vehicles, where useful.



The first demonstrator STELLA was used for initial validation of aerodynamic characteristics and controllability of the spaceplane configuration. The vehicle executed its first flight in 2020 at the airport of Rotenburg/Wümme. STELLA is not in service any more.

  • L = 2.5 m
  • 2 x kerosene-fed jet turbines



ALEDA features approximately twice the wing area of STELLA and executed its first flight in 10/2022. ALEDA was designed as a low-cost risk-reduction platform, mainly used for testing and tuning of automated flight controllers and sensors. By the end of 2022, ALEDA had already executed 19 flights at two airports without any issues.

With more sophisticated vehicles becoming flight ready, the focus of ALEDA has shifted in the meantime towards a pure drone pilot training platform.

  • L = 3.5 m
  • 4 x electric ducted fans
  • ALEDA1_1
  • ALEDA2_1
  • ALEDA3_1
  • ALEDA4
  • ALEDA5
  • ALEDA6




ATHENA was built under a contract awarded by the German Armed Forces (Bundeswehr) as part of the project “Rapid Deployable Reconnaissance System RDRS”. The vehicle successfully conducted its first flight in 11/2022 at the airport of Peenemünde. ATHENA is much heavier, more powerful and more sophisticated compared to the previous demonstrators. The vehicle features beyond visual line of sight (BVLOS) telemetry and semi-automated flight control systems, and is designed for the later integration of a liquid-fuel rocket engine. Due to its higher mass, performance and BVLOS capability, the vehicle was required to fulfil a comprehensive regulatory framework, including dedicated vehicle operation license, restricted airspace implementation, long-range radio/telemetry licenses, environmental assessment and a special insurance. For emergency cases, ATHENA is also equipped with a redundant flight termination system (FTS).

  • L = 3.5 m
  • M = 120 kg
  • 4 x kerosene-fed jet turbines
  • Designed for rocket engine installation
  • ATHENA11



MIRA is a dedicated validation vehicle for in flight-demonstration and testing of linear aerospike rocket engines. Linear aerospikes form a novel class of rocket engines that offer large performance increases compared to conventional rocket engines. Flight-testing including engine in-flight ignition and operation will be conducted under a Bundeswehr/BAAINBw study contract awarded in April 2023. The first flight under turbine power was successfully conducted on 26th of October, 2023, at Peenemünde Airport. Flights under rocket-power will follow soon. Similar to ATHENA, MIRA is licensed for BVLOS operation with a telemetry range of 20 km and is also equipped with a redundant flight termination system (FTS). MIRA is the largest and most complex vehicle built and flown by POLARIS to date. The total development time from the start of vehicle design until its maiden flight lasted only six and a half months.

  • L = 4.25 m
  • M = 210 kg
  • 4 x kerosene-fed jet turbines
  • 1 x liquid-fuel linear aerospike rocket engine
  • MIRA4
  • MIRA5
  • MIRA10
  • MIRA8
  • MIRA9
  • MIRA15
  • Aerospike6
  • Aerospike7

MIRA-Support Vehicle: MIRA-Light


MIRA-Light ("Mini-MIRA")  is a scaled-down, 2.5 m long and technologically simple version of the larger and heavier aerospike-demonstrator MIRA. The main purpose of MIRA-Light is to test and calibrate the flight control systems for its bigger sister. First flight was conducted on 22nd of August 2023. By 8th of September, just 17 days after first flight, the flight controller test program was already completed.  A total of 15 flights were conducted on three flight days.

By end of October 2023, the vehicle had accumulated a total of 26 flights at the Airports of Rotenburg/Wümme and Peenemünde.

MIRA-Light is already the 4th vehicle that we brought into the air. We designed and built the vehice in parallel to MIRA within just a few weeks.

  • L = 2.5 m
  • 4 x electric ducted fans
  • MM1
  • MM2
  • MM3
  • MM4
  • MM5
  • MM6
  • MM7



NOVA will be the final demonstrator before the spaceplane. The main purpose is the demonstration of safe and repeatable rocket-powered supersonic flight capability at high altitudes, while fulfilling the full regulatory framework required for airport-based operation. The first flight is planned for 2024.

  • L = 6-7 m
  • 4 x kerosene-fed jet turbines
  • 1 x liquid-fuel rocket engine