Polaris Spaceplanes receives MIRA II, MIRA III fiberglass airframes

Polaris receives glass fiber-reinforced polymer (GFRP) airframes for the MIRA II and MIRA III demonstrators (bottom) in its development of light and heavy spaceplanes targeted for flight by 2027 and early 2030s, respectively. Source (All Images) | Polaris Raumflugzeuge GmbH

Polaris Raumflugzeuge GmbH (Bremen, Germany) is developing a reusable space launch and hypersonic transport system that operates like an aircraft. Its development of the Aurora spaceplane is based on more than 30 years of German and European spaceplane research, which began at the DLR –German Aerospace Center. Aurora is said to combine aircraft and rocket launcher technologies with a distinctive vehicle design to offer game-changing economic viability toward routine low-cost and safe access to space.

Aurora spaceplane diagram.

Polaris’ roadmap targets a light spaceplane by 2027 and a heavy vehicle by the early 2030s. In order to validate the technology and accelerate this development, the company has built and tested a series of scaled flight demonstrators including MIRA and now MIRA-II (VCN-007) and MIRA-III (VCN-008) — all featuring an airframe made using glass fiber-reinforced composite sandwich construction.

Why spaceplanes? Traditional space transportation is based on vertically launched rockets. Although these are being developed to be increasingly reusable, rocket-propelled “spaceplanes” for horizontal takeoff offer inherent reusability and high cost savings as well as fundamental improvements in flexibility and safety. Spaceplanes can operate similar to airplanes from airports and do not require a launch pad with complex and expensive infrastructure. Studies like ESA-FESTIP identified such vehicles as the most economical solution for future spaceflight.

Light spaceplanes for lower payload masses can takeoff and land just like aircraft, Polaris reports. For heavy spaceplanes, launch support systems can be used to optimize vehicle performance.

Recently, Polaris has received the glass-fiber composite structures for its latest flight vehicles MIRA II and MIRA III. Built by Up2-Tec (Aachen, Germany), the composite airframes were delivered within a short time and cost-efficient budget.

Polaris demonstrators list.

The identical twins are 5 meters long and feature a 30% higher wing area compared to the 4.3-meter-long precursor MIRA. This increased size enables a significant boost in flight testing capabilities. The design has also been greatly improved compared to MIRA, incorporating all the lessons learned so far.

Polaris ESA space roadmap.

Each aircraft is to be equipped with four turbines and Polaris’ liquid oxygen (LOX)/kerosene linear aerospike rocket engine. The company decided to proceed with two vehicles rather than one to speed up flight testing and have a reserve aircraft.

In the coming weeks, Polaris will assemble and integrate the MIRA II and MIRA III aircraft, make them flight-ready and prepare the documentation required for licensed operation and flight-testing in September 2024. Polaris plans for the MIRA II and MIRA III aircraft to be the last pure technology demonstration vehicles. In 2025, it will build and fly the roughly 8-meter-long supersonic successor, Nova, which will be the prototype for a commercial product.