Pseudosatellites: Revolutionizing High-Altitude Platforms

Pseudosatellites, also called High-Altitude Pseudo Satellites (HAPS), are airborne platforms designed to fulfill missions traditionally assigned to regular satellites, such as communications and observation. These platforms offer 24/7 persistence at a reasonable cost. The military applications are evident, with the US Army already integrating high-altitude balloons into its operational framework. In June 2024, representatives from three companies gathered at the Eurosatory defense show to present their progress.

Companies and Their Innovations

Hemeria, Thales Alenia Space, and Airbus Defense and Space

Hemeria presented its BALMAN maneuverable balloon solution, Thales Alenia Space showcased its Stratobus dirigible, and Airbus Defense and Space unveiled its Zephyr solar-powered plane. These companies are at the forefront of developing HAPS technologies that could revolutionize various applications, from military operations to commercial communication services.

Airbus Defense and Space: Zephyr Solar-Powered Plane

Introduction and Capabilities

After an introduction by Nicolas Multan, CEO of Hemeria, Emmanuel Flory, Head of Geospatial Solutions at Airbus Defense and Space, emphasized that Airbus views HAPS as a natural extension of its business. Airbus already designs and operates observation satellites like Pleiades Neo, and it aims to complement these services with the capabilities of HAPS. The Zephyr solar plane, a British-built lightweight airframe weighing only 65kg with a 25m wingspan, is central to this plan. Its first long-duration flight occurred in 2018, lasting three weeks. Certification is expected in 2025, making it the first HAPS of its kind.

Future Plans and Business Model

Airbus recently formed Aalto, a subsidiary dedicated to developing and commercializing Zephyr. Aalto’s primary business model involves providing stratospheric 5G services, potentially replacing around a hundred 5G towers with a single plane, making 5G coverage more affordable in sparsely populated areas. A consortium of Japanese communications operators has already invested 100M€ in Aalto. Airbus aims to scale up to hundreds of Zephyrs in the air within a few years, enabling economies of scale and making the planes more affordable for defense and other uses.

Thales Alenia Space: Stratobus Dirigible

Overview and Development

Michel Masselin, Commercial Director at Thales Alenia Space (TAS), provided an overview of their Stratobus solar-powered dirigible. Unlike Zephyr, Stratobus is filled with helium, making it lighter than air and giving it rigidity. The full version will be 140m long, with 16,000 m² of solar cells providing power to the engines and delivering up to 5kW to a payload of up to 250 kg. This large capacity and the available space at the bottom of the platform make Stratobus ideal for carrying optical and radio payloads, radars, and even combinations of payloads.

Operational Plans and Business Model

Stratobus will operate on a traditional business model, where customers, primarily defense clients, purchase the platform. The full-size Stratobus is expected to be operational by 2030. TAS will start with a smaller demonstrator, 60 meters long, with the first flight planned for the end of 2025 from the Canary Islands. This demonstrator will test LIDAR mapping and communication intelligence missions.

Hemeria: BALMAN Maneuverable Balloon

Project Details and Advantages

The balloon has a diameter of 20m and an envelope height of 15m, carrying a payload of 12 to 25kg along with solar panels for power. Operating between 16 and 25km altitude, where winds are stable and turbulence is low, the balloon can adjust its altitude to steer its direction. This capability allows it to stay within a 100km-wide area, providing persistent coverage.

Testing and Future Applications

The first balloon envelope test is planned for 2024 from the French Guiana Space Center, with full maneuver testing scheduled for 2025. BALMAN is simpler to launch than Zephyr or Stratobus and can reach its operating altitude within four hours. Its flexibility makes it suitable for naval applications, where balloons can be launched from a frigate’s helicopter deck to provide communication or intelligence services over wide areas.

Conclusion

The three projects—Zephyr, Stratobus, and BALMAN—are nearing operational status, with 2025 set to be an exciting year. The Zephyr’s certification and Mediterranean demonstration tour, the Stratobus demonstrator’s first flight, and BALMAN’s initial maneuvers are all highly anticipated. Interestingly, the companies are both competitors and partners, with Hemeria building Stratobus’s envelope and Airbus providing a payload for BALMAN. The combination of civilian and military markets should ensure the continued development and deployment of these innovative HAPS solutions, each with its unique advantages.