Skydweller Aero landed at the 2024 Farnborough International Airshow this week with an update on its progress toward its established goal of flying its uncrewed solar aircraft autonomously nonstop around the world. It exhibited with Kallman Worldwide, Inc. in its USA Pavilion, and President & COO Barry Matusmori presented on the company’s journey, the aircraft’s capabilities, and an update on aircraft flight operations. Before joining Skydweller, Matusmori was the COO of Impulse Space and had executive leadership roles at SpaceX and Virgin Orbit.

Others have achieved elements of the company’s goal of autonomous, nonstop solar power around the world flight, “but no one has ever even attempted what we intend to do,” posted Greg Caires, Communications Director for Skydweller Aero, on LinkedIn. He cited Lucky Lady II, a U.S. Air Force Boeing B-50 Superfortress that became the first airplane to circle the world nonstop in 1949, Scaled Composites’ Voyager, Virgin Atlantic’s GlobalFlyer, and even Solar Impulse 2 that Skydweller purchased in 2019.

Primarily backed by venture and private capital, the pioneering transatlantic aerospace company has global and U.S. headquarters in Oklahoma City, OK, with research and development facilities in Madrid, Spain. It is developing and manufacturing a fleet of large solar-powered aircraft to be capable of achieving perpetual flight with heavy, powerful payloads. Primary uses are for long-duration missions such as providing continuous coverage above war zones, surveilling naval activity in contested waters, detecting drug smugglers and pirates at sea, and tracking wildlife migration and poaching in Africa.

The design of the Skydweller has been optimized and refined for over a decade, minimizing weight, and maximizing strength and rigidity. The aircraft is manufactured from carbon fiber with a wingspan greater than a 747 but weighs only 2500 kg (5500 lb) at maximum capacity and can carry up to 800 lb (360 kg) in payload.

Because Skydwellers are solar-powered, they are inexpensive to operate and maintain and feature zero carbon footprint. Enabling this performance are advances in solar-cell technology to maintain flight, power avionics, and payloads, and charge the batteries.

In April, the company said it completed the world’s first successful autonomous/unmanned/uncrewed flight of its solar-powered aircraft, taking off, flying, and landing by itself, without humans on board or in control, from Stennis International Airport in Hancock, MS.

“This is a true, world-changing first in the aerospace industry,” said Robert Miller, CEO of Skydweller Aero. “Our fleet of uncrewed aircraft will enable a multitude of long-duration missions that support national security and non-terrestrial communications with revolutionary cost savings.”

Current combustion-powered aircraft, including piloted aircraft and drones, are limited to about 40 h of maximum flight time by the endurance of pilots, the amount of fuel a conventional aircraft can carry, and the need for frequent maintenance, according to the company. In contrast, its aircraft is capable of staying aloft for 90 days or more, at altitudes of up to 45,000 ft (13,700 m).

“We are applying cutting-edge, 21st Century materials science, artificial intelligence, and software development to an industry that has spent more than 100 years building piloted, combustion-based aircraft,” added Miller. “This allows Skydweller to leap ahead of heritage aircraft manufacturers in terms of aircraft performance, flight duration, and cost-effectiveness.”

The company says that its customers can accomplish missions with a single aircraft that historically required a fleet of conventional aircraft, flight crews, and maintenance personnel. A single Skydweller aircraft capable of perpetual flight, coupled with minimal operating personnel, replaces nearly all of the costs for the same mission. So, its solar-powered aircraft is said to be 10 to 100 times less expensive to operate than conventional aircraft for long-duration missions.

Its autonomous aircraft can directly save lives by removing the need for flight crews to be physically present in hostile or dangerous airspace. For example, a Skydweller can take off from the U.S., fly to the South China Sea, and stay in the air on-mission for weeks or months before returning home. Additionally, autonomy enables not just traditional long-duration missions, but also new missions that would have formerly been deemed unacceptable due to risk to the flight crew.

Historically, solar aircraft are light and fragile, frequently experiencing catastrophic in-flight structural failure when climbing or descending through medium altitudes. Skydweller is designed to operate in this regime and has been proven in real-world conditions with a perfect flight safety record across thousands of flight hours. Automatic gust-load alleviation software is being incorporated into the flight-control system to reduce aerodynamic loads due to turbulence, enabling company structural engineers to further reduce airframe weight.

The fully autonomous aircraft leverages multiple sensors and a high-performance compute platform to perform complex missions under the guidance and direction of operators thousands of miles away. It can collect and disseminate large amounts of data that algorithms then process for mission objectives.

Skydweller is partnering with leading, antenna, modem, and networking solution providers to develop the aircraft’s aerial network layer. Its flexible payload system is supported by advanced surveillance packages, 4G/5G terrestrial communications networks, communications relay capabilities, and beyond-line-of-sight satellite communications.

The company adopted Ansys’ Safe Systems solution and deployed a holistic MBSE (Model Based Systems Engineering) methodology for safety using a single toolchain to develop its autonomous flight control and power management systems.

Operating an aircraft continuously and reliably for up to 90 days requires an extreme level of redundancy across flight-critical components. Skydweller is built around a safety-qualified, quadruple-redundant flight control system and vehicle management system (VMS).

Advanced self-healing algorithms within the VMS enable a failed string to be autonomously shut down, fixed, and resurrected during flight to return the aircraft to quadruple redundancy. This enables the aircraft to consistently achieve unprecedented flight endurance while meeting the highest levels of safety, reliability, and effectiveness.