Solar-powered aircraft developer Skydweller Aero has completed an initial test campaign of the company’s eponymous uncrewed aerial system (UAS).

The Oklahoma-headquartered firm on 30 September said the Skydweller UAS successfully conducted a series of autonomous long-duration flights in recent weeks, including one sortie lasting 22h 30min and another spanning 16h.

The flights were launched from Stennis International airport in Kiln, Mississippi under a technology demonstration programme with the US Navy (USN). That service is evaluating the Skydweller concept for potential as an autonomous maritime patrol aircraft.

“This flight-test campaign is an important achievement and validates our business vision, marking a new era in autonomous aviation,” says Robert Miller, Skydweller Aero’s chief executive and co-founder.

Skydweller inflight 3

Source: Skydweller Aero

The Skydweller UAS successfully conducted a series of autonomous long-duration flights over Mississippi in recent weeks, including one sortie totalling 22h 30min and another spanning 16h

Skydweller says its aircraft’s wingspan is equivalent to that of a Boeing 747 and that the UAS can carry 363kg (800lb) of payload. The craft has four propellers and solar panels mounted atop its horizontal stabiliser, fuselage and wings.

Onboard batteries provide power in the absence of direct sunlight.

The immediate goal of the Skydweller test programme is to prove the capability of “extreme flight endurance”, using solar-powered propulsion to produce a craft capable of remaining airborne for “weeks to months”, Skydweller Aero says.

Longer-term, Miller says the company aims to achieve “perpetual flight” – an aircraft that can essentially remain aloft indefinitely.

To do achieve that, Skydweller Aero chief operating officer Barry Matsumori says the company is incorporating technological breakthroughs related to solar energy, battery storage and carbon-fibre assemblies with high strength-to-weight ratios.

The USN provided Skydweller Aero a $5 million research and development contract in 2021 to help fund flight demonstrations of the long-endurance solar-powered concept vehicle. The company has also raised a substantial amount of capital from venture firms.

US artificial intelligence firm Palantir in 2021 signed an agreement to use its Foundry AI software to analyse data gathered by Skydweller.

That combination of long-endurance, autonomous flight and AI analysis is an appealing proposition for the navy maritime patrol mission, which involves long hours of flying low over the water hunting for enemy submarines.

One Lockheed P-3 Orion pilot formerly with the USN told FlightGlobal in 2022 that such missions are often “quite boring”, consisting of flying in circles for 8-10h.

In addition to crew fatigue, manned patrol flights are limited by a conventional aircraft’s supply of consumables – not a concern for an autonomous vehicle drawing power from sunlight.

Skydweller envisions a range of civil and military uses for the concept aircraft, including surveillance of pirates and drug smugglers, tracking wildlife migration and poaching, and intelligence collection over war zones. 

Competitors including Airbus-owned AALTO and AeroVironment are also developing solar-powered endurance aircraft for potential military applications.

More photographs of Skydweller in operation: