AALTO HAPS Ltd., an Airbus subsidiary, is ready to accelerate testing of its Zephyr High Altitude Platform Station (HAPS) after a successful 13-day debut flight over Kenya. This initial sortie marks a significant step towards commercializing stratospheric operations and integrating HAPS technology into the broader aerospace, defense, and connectivity ecosystems.
Zephyr’s Maiden Voyage from Kenyan Base
In January 2025, AALTO conducted its first successful stratospheric flight and testing from its purpose-built HAPS facility (AALTOPORT) in Laikipia County, Kenya. The Zephyr, a solar-powered, ultra-long-endurance aircraft, soared above 60,000 feet for over 13 days, demonstrating its capabilities as a high-altitude pseudo-satellite.
Key Highlights of the Test Flight:
- Connectivity Payload Testing: Zephyr carried a direct-to-device (D2D) 4G/5G connectivity payload developed at AALTO’s Farnborough headquarters. The tests aimed to evaluate the performance of the connectivity system, ensuring compatibility with smartphone technology for video and data services.
- Flight Envelope Validation: AALTO validated improvements to Zephyr’s flight envelope, enhancing its stability and performance. The aircraft was intentionally brought down to 55,000-60,000ft several times to assess its maneuvering characteristics.
- Regulatory Breakthrough: The establishment of AALTOPORT in Kenya followed 18 months of regulatory engagement and technical studies, setting an unprecedented pathway for commercial HAPS operations.
Kenya: A Hub for Stratospheric Innovation
Kenya’s strategic vision and regulatory support have been instrumental in AALTO’s progress. The Kenya Space Agency (KSA) and the Kenya Civil Aviation Authority (KCAA) have facilitated flight authorizations, positioning Kenya as a pioneer in stratospheric technology.
Quotes
Brigadier Hillary Kipkosgey, Acting Director General / CEO of the Kenya Space Agency, emphasized Kenya’s commitment to advancing near-space technologies:
“As the national regulator for space activities and coordinating agency for the multi-agency team on stratospheric operations, the Kenya Space Agency is committed to promoting the adoption and use of enabling technologies that are innovative, secure, and impactful. HAPS is a unique capability with critical applications across multiple sectors. Through our support to AALTO, we are pleased to demonstrate Kenya’s global leadership in creating a new hub for near-space technology.”
AALTO CEO Hugues Boulnois highlighted the Zephyr HAPS’ transformative potential:
“Zephyr’s return to stratospheric testing and operations is a significant milestone in its commercial roadmap. As the most established platform globally, Zephyr continues to showcase its capabilities across connectivity and Earth observation applications. It is a complementary asset to traditional space and defence ecosystems with unrivalled performance, flexibility, and a payload-agnostic design. Thanks to the strategic vision of Kenyan regulators, we are now one step closer to commercialising the stratosphere.”
Zephyr: A Flying Cell Tower
Zephyr offers a cost-effective alternative to traditional satellite connectivity solutions and ground-based cell towers. Its ability to deliver low-latency, high-bandwidth cell phone communications directly to handsets makes it ideal for expanding mobile network coverage in remote areas.
Potential Applications:
- Connectivity in Remote Areas: Zephyr can augment existing cell phone networks, providing connectivity where building traditional cell towers is prohibitively expensive.
- Early Detection of Forest Fires: Zephyr can support national efforts to improve the early detection of forest fires.
- Disaster Response: As demonstrated during a cyclone in Mayotte, HAPS can restore connectivity in disaster-stricken areas.
AALTO’s Commercial Roadmap
AALTO plans to launch commercial services in 2026 with the HAPS Japan venture, involving NTT Docomo and Space Compass. The company will gradually enter service, initially focusing on governmental customers. AALTO aims to achieve 200 days of on-station capability, pushing the boundaries of HAPS technology.
Key Objectives for 2025:
- Integrate HAPS into the space, defense, and connectivity ecosystems.
- Progress the commercial phase for this pioneering technology.
Zephyr’s Record-Breaking Flight
Zephyr has a track record of groundbreaking achievements. On April 28, 2025, it concluded 67 days, 6 hours, and 52 minutes of continuous flight in the stratosphere, surpassing its previous record of 64 days in 2022. The record-breaking flight was facilitated by the regulatory framework in Kenya.
Flight Highlights:
- Launched from AALTOPORT in Kenya on February 20, 2025.
- Conducted connectivity payload testing.
- Transited to Australian airspace.
- Navigated 7 different flight information regions, the most ever recorded by a HAPS.
- Crossed the Intertropical Convergence Zone (ITCZ) twice.
- Terminated safely over a designated aviation sanctuary area in the Indian Ocean.
The Future of HAPS Technology
AALTO’s Zephyr is at the forefront of innovation in aerospace, pushing the boundaries for the burgeoning HAPS industry. Its unique capabilities, technological robustness, and compliance with flight procedures and safety models make it a valuable asset for commercial and government partners. With ongoing testing and development, AALTO is poised to revolutionize connectivity and Earth observation, bridging the gap between aerospace and satellite services for global markets.
