HALIFAX, Nova Scotia – The British Defence Ministry on Aug. 17 said it had exercised an option for a third solar-powered, high-altitude surveillance and communications platform from Airbus Defence and Space, with flight trials to begin in mid-2017.

The Airbus Zephyr-S aircraft, one of several designs of what are called high-altitude pseudo satellites, or HAPS, is designed to operate for up to 45 days before landing for refurbishment and to provide a range of persistent surveillance and communications services.

The Defence Ministry has not disclosed how it intends to use the vehicles, the first two of which were purchased in February under a contract valued at 13 million British pounds ($17.4 million).

“The additional Zephyr-S will allow 2 airframes to be tested simultaneously and demonstrate operational handover to show that the capability could be sustained indefinitely,” the ministry said in a statement. “The OCD (Operational Concept Demonstrator) trials, which will be held in 2017, will inform Defence’s decisions around how best to provide next-generation battlefield intelligence to the UK Armed Forces.”

Airbus said the Zephyr-S version, with a 25-meter wingspan, is 30 percent lighter than its predecessor and can carry 50 percent more batteries, boosting the amount of surveillance or communications payload it can carry.

The company said Zephyrs, to operate at 65,000 feet in altitude above air traffic, “can be used for humanitarian missions, precision farming, environmental and security monitoring, and to provide internet coverage to regions of poor or zero connectivity,” in addition to military missions.

British Defence Secretary Michael Fallon said in a statement:

“Zephyr is a cutting-edge, record-breaking piece of kit that will be capable of gathering constant, reliable information over vast geographical areas at a much greater level of detail than ever before.

“They are part of our plan for stronger and better defence, backed by a budget that will rise each year of this decade. That means more ships, more aircraft, more troops available at readiness, better equipment for special forces, more being spent on cyber – to deal with the increased threats to our country.”

Zephyr is one of several HAPS designs being developed in Europe and the United States. The French government is providing funds to develop a stratospheric HAPS called Stratobus, whose initial market is expected to be for Earth observation. The U.S. Army has contracted with Lockheed Martin to test Lockheed’s High Altitude Long Endurance-Demonstrator (HALE-D) in view to development of a larger, operational High-Altitude Airship.

Peter B. de Selding was the Paris bureau chief for SpaceNews.