AALTO HAPS aircraft is pictured on the ground, as the sun sets.

Press Release: AALTO, Space Compass eye solar-electric tower in the sky


Press Release hub banner blue with title in red white and blueAALTO HAPS has signed a contract to partner in a proof of concept (PoC) demonstration flight of its world-record-breaking Zephyr High Altitude Platform Station with Space Compass of Japan — a joint venture between NTT and SKY Perfect JSAT. 

In 2023, AALTO will fly a Zephyr Z8B aircraft equipped with a mobile communications payload on another stratospheric flight to demonstrate full operability of a solar-electric “tower in the sky”; a technology enabling a cost effective expansion of connectivity coverage to rural and remote areas. 

To date, AALTO’s Zephyr is the only HAPS to have proven day and night longevity in the stratosphere, having already demonstrated 64 consecutive days during the 2022 flight trial. 2023 flight tests will give further focus to  showcasing stratospheric connectivity operations, building upon 2022’s success to extend flight longevity. 

Use cases will include coverage-as-a-service: the ability for Zephyr to deliver year-round 4G/5G low latency mobile connectivity to serve areas previously challenging to cover; network augmentation — to provide overlay or infill coverage to close connectivity white spots, where terrestrial coverage cannot deliver complete or additional capacity; and disaster recovery — the ability to offer connectivity when terrestrial coverage is temporarily cut, and restoring the service becomes a critical life-saving mission. 


Space Compass’ involvement in this year’s PoC flight with AALTO continues to demonstrate Japan’s early leadership in building the HAPS use cases, and showcasing the maturity, and readiness of Zephyr’s stratospheric capabilities.

With AALTO, Space Compass is working on developing a communications and earth observation service using HAPS starting in Japan, as a part of Space Compass’ vision to build a “Space Integrated Computing Network”. 

Further connectivity PoC flights are planned for 2024 with the intention for AALTO’s Zephyr to fully enter into commercial service at the end of the year. 

AALTO HAPS Zephyr Takeoff at sunset

Zephyr flies in the stratosphere, on solar energy, above conventional air traffic and provides low-latency, direct-to-device 4G/5G services. It acts as a tower in the sky with the capability to complement terrestrial networks. 

AALTO HAPS is an Airbus subsidiary that provides services from its stratospheric Zephyr solar-powered aircraft for Mobile Connectivity, Platform Mobility, Earth Observation, and Government applications.

All images credited to AALTO HAPS