The world’s first Zephyr operating base was launched earlier this week at Wyndham Airfield in WA.
Zephyr is an unmanned aerial vehicle (UAV) completely solar powered with integrated li-ion batteries that enable its long flights. It operates in the stratosphere at an average altitude of 21 kilometers, above weather and regular air traffic.
According to Airbus, the original target mission of the Zephyr is to revolutionise defence, humanitarian and environmental missions all over the world. The multi-flight solar-powered aircraft aims to provide a wide scope of applications, ranging from maritime surveillance and services, border patrol missions, communications, forest fire detection and monitoring, or navigation.
The reasons behind the decision to establish its first operating base in WA was the largely unrestrictive airspace, and reliable weather conditions in the Kimberley region, which make Wyndham the ideal site for Zephyr flights.
“We are proud to see Australia become part of the Zephyr operational network. The site is our gateway to the stratosphere and will be the main flight base for Zephyr going forward,” said Jana Rosenmann, Head of Unmanned Aerial Systems at Airbus.
The project is also expected to bring economic benefits to the East Kimberley region, with up to 20 Airbus staff to be based in the local area during operational phases providing a boost to local businesses.
“Securing the world-first Zephyr operating base in WA demonstrates our State has the capacity, geography and local workforce to establish thriving defence and space sectors,” WA Premier Mark McGowan said addressing the opening ceremony.
There are two versions of Zephyr. The S model, which has a wingspan of 25m and weighs less than 75kg, and the T model with a wingspan of 33m and weighs 140kg, which is currently in development.
During its maiden flight in August, Zephyr S stayed in the air 25 days, 23 hours, and 57 minutes, which qualified as the longest duration flight ever made.
The previous longest flight duration record was also logged by a Zephyr prototype aircraft a few years earlier, achieving then more than 14 days continuous flight, which already was ten times longer than any other aircraft in the world.
The technology behind – silicon nanowire anodes
In a separate press release, manufacturer and developer of high energy and high capacity lithium-ion batteries Amprius announced it was supplying advanced lithium ion cells to the Airbus Defence and Space Zephyr Program.
Noting that its batteries powered Zephyr’s maiden flight, Amprius underlines that the key to the energy density and cycle life of its li-ion batteries are 100% silicon anodes.
While silicon anodes have much higher specific capacity compared to graphite anodes which are used in conventional lithium ion batteries, in particle or film structures silicon is not stable and lasts only a few recharge cycles.
But, according to Amprius, its silicon nanowire structures overcome this instability and thereby enable hundreds of cycles with specific energies of over 435 Wh/kg and energy densities in excess of 1200 Wh/liter.
“Our collaboration with Amprius in the application of their silicon nanowire based lithium ion cells to the Zephyr has been important to the success of the HAPS program,” said Sophie Thomas, Airbus HAPS Program Director.
“The high specific energy of Amprius batteries enable the Zephyr to fly uninterrupted in the stratosphere which would not be possible with lower performance batteries.”
Airbus has not specified the type of solar cells incorporated into the aircraft’s design.