The Boeing Phantom Eye is a high altitude, long endurance (HALE) liquid hydrogen-powered unmanned aerial vehicle developed by Boeing Phantom Works system for persistent intelligence, surveillance and reconnaissance and communications missions. The Phantom Eye is Boeing's proposal to meet the demand from the US military for unmanned drones designed to provide advanced intelligence and reconnaissance work, driven by the combat conditions in Afghanistan in particular.
Phantom Eye is capable of maintaining its altitude for up to four days while carrying a 450-pound payload. Typical payloads include multiple sensor packages for monitoring, tracking and communications. A full size Phantom Eye variant is designed to stay aloft for up to ten days and carry a payload of 2,000 pounds.
Revealed to the press at a ceremony at Boeing's facilities in St Louis, Missouri, on July 12, 2010 the Phantom Eye demonstrator is a 60%-70% scale design of an objective system. According to Darryl Davis, president of Boeing's Phantom Works advanced concepts group, the Phantom Eye demonstrator could lead to an objective system capable of achieving 24-hours-a-day, seven-days-a-week coverage of an area year round with as few as four aircraft.
Boeing has also been studying a larger HALE UAV that can fly for over 10 days and carry payloads of 2,000 pounds (900 kg) or more; the company is also working on the Phantom Ray UAV as a flying test bed for advanced technologies.
The Phantom Eye demonstrator has a 150-foot (46 meter) wingspan and is powered by two modified Ford 2.3 litre engines, reduction gearbox and two 4-blade propellers. The engines were originally designed for use with some models of the petrol-burning Ford Fusion car. To be able to run in the oxygen starved atmosphere at 65,000 feet, the engines feature a multiple turbocharger system that compresses available low density air and reduces the radiated infrared heat signature to increase its stealth properties. The engines, which provide 150 horsepower at sea level, have been tuned so as to be able to run on hydrogen. Boeing's marketing department states that this will make the aircraft economical and "green" to run, as the only by-product will be water.
Phantom Eye's first medium-speed taxi test took place at NASA's Dryden Flight Research Centre at Edwards Air Force Base on March 10, 2012 when it reached speeds of 30 knots. Boeing declared the test a success and said it paved the way for the aircraft's first flight, expected to last 8 hours. The first flight took place 1 June 2012 and lasted 28 minutes during which an altitude of 4,000 feet was reached. The landing gear dug into the dry lakebed and caused some damage to the aircraft.
On February 6, 2013, sitting atop a launch cart, it reached speeds of 46 mph. Autonomous flight systems were upgraded and the landing system was improved in preparation for the second flight. The second flight was completed on25 February 2013. The Phantom Eye climbed to an altitude of 8,000 feet at a cruising speed of 62 knots (71 mph) for 66 minutes. The landing was uneventful.
Boeing was issued a $6.8 million contract by the U.S. Missile Defence Agency on 6 June 2013 to install an unidentified payload on the Phantom Eye demonstrator. The payload was most likely a long-range sensing and tracking system required to aim a laser.
The Phantom Eye's fourth flight occurred on June 14, 2013 during which it reached an altitude of 20,000 feet. It stayed aloft for four hours. On September 14, 2013, its fifth flight reached an altitude of 28,000 feet for nearly four and a half hours. The fifth flight incorporated a payload from the Missile Defence Agency.] The sixth flight occurred on January 6, 2014 and lasted for 5 hours, longer than any previous flight.
In February 2014, the Phantom Eye was promoted to experimental status by the Air Force's 412th Operations Group on recommendation from NASA's Dryden Flight Research Centre. Classification as experimental under the USAF Test Centre means it is no longer restricted to flying above Edwards AFB and will move to a test range several miles away to further endurance and altitude capabilities.
The demonstrator's ninth flight occurred in 2014 and last for 9 hours at 54,000 feet. In the coming months Boeing will test the demonstrator to reach its desired operating altitude of 60,000 feet (18,000 m) and increase its endurance. If successful, a full-size operational Phantom Eye will be built to reach endurance goals of 7-10 days airborne with a payload of 2,000 lbs.
Boeing is looking for opportunities in the military or commercial sectors to continue development. Initially pitched as a high-flying satellite surrogate for ground surveillance or communications relay, the company is looking to see if a solid-state laser could be mounted to perform missile defence; a solid-state laser is desired over chemical lasers, like the one used in Boeing's previous YAL-1 Airborne Laser test bed, because there is a shorter logistical tail and less time is needed to recharge and cool.