High altitude platform stations (HAPS) are back in the news at MWC25 with an announcement from AALTO, an Airbus subsidiary which designs, manufactures and operates the Zephyr HAPS. AALTO says it has completed successful connectivity testing in Kenya on behalf of its customer Space Compass Corporation and partner NTT DoCoMo, Japan’s leading mobile operator.
AALTO designs, manufactures and operates the solar-powered Zephyr HAPS aircraft, which flies in the stratosphere above conventional air traffic to provide low-latency, direct-to-device 4G and 5G services.
Zephyr was equipped with a connectivity payload that made direct communication to a 4G mobile device on the ground and a direct-to-device gateway station in Kenya.
This is the first wireless connection achieved by a fixed-wing HAPS flying continuously above 60,000 feet (18,288 metres) which included a telephone call from the site in Kenya via Zephyr which was transmitted to the UK over a local internet link. In addition to this milestone, AALTO conducted different tests to characterise the performance of the connectivity system including measuring throughput and overall signal quality.
NTT DoCoMo, Japan’s leading mobile operator, and Space Compass, a joint venture between NTT and SKY Perfect JSAT, are part of the HAPS Japan consortium that committed to a US$100 million investment in AALTO in 2024. HAPS Japan, AALTO and Airbus Defence and Space are establishing a roadmap for commercial HAPS services to begin in Japan from 2026.
This connectivity demonstration was facilitated by the establishment of a comprehensive regulatory framework in Kenya, the location of AALTO’s launch and landing site for Zephyr.
The Kenya Space Agency is the primary regulator for stratospheric operations, supported by partners that include the Kenya Civil Aviation Authority. Connectivity testing was facilitated by the Communications Authority of Kenya.
Recent AALTO news in these pages includes MoUs in Indonesia and Saudi Arabia.
