The recent diplomatic scandal caused by the shooting down of a Chinese balloon over the United States has brought attention to the use of the stratosphere for spying purposes. However, for companies like Stratospheric Platforms, thinking about stratospheric objects is just a regular day at the office. These companies are part of a new generation that aims to fill the higher reaches of the Earth’s atmosphere with uncrewed aircraft that can stay there for weeks or even months at a time.
Stratospheric Platforms, based in Cambridge, is planning to add a High-Altitude Pseudo Satellite (HAPS) to the stratosphere. The company has raised over $85m in capital from German telecom company Deutsche Telekom and is currently in a fundraising round hoping to add another $160m to that number. Its idea is to use HAPS to provide telecommunication services from the stratosphere.
Other large investors and aerospace players, such as SoftBank, BAE Systems, and Boeing, are also testing or have proposed HAPS designs. According to research firm Northern Sky Research, the market for stratospheric aircraft, which includes HAPS as well as balloons that use high altitudes for services like predicting the weather, would amount to $4bn in cumulative revenues by 2029. It also predicted annual growth in revenues of 13 percent during that period.
Airbus is one of the companies that has the most advanced HAPS design with its Zephyr. The aircraft has a wing span of 25 metres and is powered by solar energy. During the day, solar panels charge batteries that keep the aircraft flying at night. In 2022, one of Airbus’s aircraft flew for 64 days straight after which it was lost. The Zephyr is currently going through the certification needed to make its commercial debut, which is scheduled to happen around the end of 2024.
HAPS will mainly be used in ways similar to satellites. They could connect people and households on the ground, particularly in badly-connected areas, or they could do earth observation, gathering information on issues like economic flows or weather patterns. Military and national security applications are also being considered, such as spying or monitoring borders.
However, HAPS have been around for a long time, and so far, most companies have failed at making the technology work in a way that is commercially attractive. According to Samer Halawi, CEO of AALTO HAPS, the Airbus spin-off dedicated to commercialising the Zephyr, the technology has since changed and is nearing commercial readiness. Aircraft materials have become lighter, solar panels have been introduced, and batteries are improving rapidly.
Offering telecommunication services might be one key market for HAPS. For Stratospheric Platforms, its design could serve as the missing link for telecom networks in rural and remote areas where operators are reluctant to build expensive infrastructure for relatively low amounts of customers.
Stratospheric Platforms’s HAPS design is still in the concept stage and has not yet flown, unlike the Zephyr. The company hopes its aircraft will fly in the first half of 2025, with a full entry into service in 2026. The design also diverges from that of the Zephyr. Stratospheric Platforms wants to power its craft with hydrogen, not solar energy. This would mean less flight time but could also allow heavier equipment on the craft. The design would be bigger as well, with a 60-metre wingspan.
It remains to be seen whether the technology can actually reach commercial success. According to Hussain Bokhari, a senior analyst at Northern Sky Research, “HAPS need to show real-world value. The technology still needs to become more concrete and it needs to show how it relates to existing options, like satellites or ground-based infrastructure.” However, proponents believe that HAPS have what it takes to succeed. They offer better connections than satellites, can take more granular images if flying lower, and do not need to be launched into space, which reduces costs.
In conclusion, the use of the stratosphere for commercial purposes is a booming new field that could potentially fill the higher reaches of the Earth’s atmosphere with uncrewed aircraft. Companies like Stratospheric Platforms and Airbus are leading the way in developing HAPS designs that could provide telecommunication services, do earth observation, or have military and national security applications. However, the technology still needs to show real-world value and become more concrete to reach commercial success.