Aerospace Defence Space

Zephyr completes stratospheric flight testing from Kenya base

Posted 3 February 2025

AALTO HAPS has completed its first stratospheric flight and testing from its purpose-built HAPS facility (AALTOPORT) in Laikipia County, Kenya, successfully testing its UK-built connectivity payload - a key use case of the payload-agnostic Zephyr platform - whilst simultaneously completing the longest ever unrefuelled flight over Africa and the highest flight over the entire continent.

Above: Zephyr in its Kenya hangar.
Courtesy AALTO HAPS

Flying for more than 13 days above 60,000ft in Kenya, Zephyr was equipped with a payload developed at AALTO’s Farnborough headquarters that can provide direct-to-device (D2D) 4/5G connectivity. Compatible with smartphone technology to enable video and data services, AALTO conducted tests to characterise the performance of the connectivity system. During the flight, AALTO also validated improvements to Zephyr’s flight envelope to provide greater stability and performance.

AALTO - an Airbus subsidiary which designs, manufactures and operates the Zephyr High Altitude Platform Station (HAPS) - secured permissions to establish an AALTOPORT for stratospheric operations during 2024, following 18 months of regulatory engagement and technical studies to facilitate flight approvals.

With the support of the Kenya Space Agency and Kenya Civil Aviation Authority, Kenya has consolidated its position as a pioneer for HAPS innovation and enabled AALTO’s global expansion.

Hughes Boulnois, CEO of AALTO, commented: “Zephyr’s return to stratospheric testing and operations is an important step in its commercial roadmap. Stewarding the most established platform globally, AALTO is demonstrating the capabilities of Zephyr from a payload and platform perspective.

"With unrivalled performance and flexibility, alongside game-changing applications as a payload agnostic platform, AALTO’s Zephyr is a naturally complementary asset to traditional space and defence ecosystems.

“For many years we have worked with strategic partners on promoting technological innovation and opportunities across connectivity and Earth observation markets. Now thanks to the strategic vision of Kenyan regulators, we are one step closer to commercialising the stratosphere.”

Brigadier Hillary B Kipkosgey, Acting Director General / CEO of the Kenya Space Agency, added: “As the national regulator for space activities and coordinating agency for the multiagency team on stratospheric operations, the Kenya Space Agency is committed to promoting adoption and use of enabling technologies that are innovative, secure and impactful.

“HAPS is a unique capability with potential use cases that Kenya recognises as critical to many stakeholders. Through our support to AALTO, we are pleased to demonstrate Kenya’s global leadership in creating a new hub for near space technology.”