Unmanned solar plane that has to stay in the air for a year makes its first flight

Phasa-35, a solar plane with a wingspan of 35 meters, has completed its maiden flight. According to one of the manufacturers, BAE Systems, this paves the way for the aircraft to become a game changer and fill the gap between aircraft and satellite technology.

The Phasa-35 has completed its first test flight over the Australian test site of Woomera in the state of South Australia. According to Sky News, among others, the plane has reached an altitude of about two kilometers. The aircraft has completed a number of critical functional and performance tests, looking specifically at aerodynamics, propulsion and energy efficiency. The plane flew and landed completely autonomously, writes Prismatic Ltd, a company acquired by BAE Systems. The two companies are jointly working on the Phasa-35 project.

The Phasa-35 is listed as a High Altitude Long Endurance vehicle. It is an aircraft that flies entirely on solar energy, in which the solar cells in the wings charge the batteries. The aircraft should eventually be able to fly in the stratosphere at an altitude of about 20 km for up to a year. This is possible due to the efficiency of the flight, the propulsion and the energy systems. Phasa-35 uses lithium-ion batteries and GaAs solar panels that achieve higher efficiency than silicon-based panels. It makes it possible to stay in the air at a high altitude with a minimal amount of energy. The aircraft is fairly similar to Airbus’ Zephyr S HAPS, which flew for nearly 26 days in August 2018.

The aircraft weighs 150kg, including the maximum payload of 15kg, and can be used for a variety of applications, such as maritime surveillance or forest fire detection. Phasa-35 can perform these tasks at a fraction of the cost of satellites, BAE Systems said. The vehicle can also play a role for communication networks, in which the companies are also thinking of 5G applications. The project is sponsored by the British Defense Science and Technology Laboratory and the Australian Defense Science and Technology Group. This has to do with the expectation that Phasa-35 can also play a role in the military field, for example for the Future Combat Air System.

BAE Systems says it designed, built and flew the aircraft in 20 months. More test flights should take place in the course of this year. During that new phase, longer endurance tests should be performed. Once the test program has been completed, the aircraft could begin initial operations for customers within 12 months, according to BAE.