The Boeing SolarEagle (Vulture II) was a proposed

High-Altitude Long Endurance Atmospheric satellite (United States usage, abbreviated atmosat) or pseudo-satellite (British usage) is a marketing term for an aircraft that operates in the atmosphere at high altitudes for extended periods of time, in order to provide servic ...

(HALE)

unmanned aerial vehicle An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without any human pilot, crew, or passengers on board. UAVs are a component of an unmanned aircraft system (UAS), which includes adding a ground-based controller ...

solar-

electric Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by ...

spy plane developed by

Boeing Phantom Works Boeing Phantom Works is the advanced prototyping arm of the defense and security side of Boeing. Its primary focus is developing advanced military products and technologies, many of them highly classified. Founded by McDonnell Douglas, the res ...

.Haddox, Chris
"SolarEagle (Vulture II) Backgrounder"
''Boeing Phantom Works'', September 2010. Retrieved: 18 October 2010. The proposed aircraft had a

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the other wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingspan of ...

of 393.7 feet (120 meters), and was intended to remain airborne for up to five years at a time without needing to land. It had 20 motors of the same type as the

Qinetiq Zephyr The Airbus Zephyr is a series of lightweight solar-powered unmanned aerial vehicles (UAV). The latest model is a high-altitude platform station capable of flying at for months at a time without fueling. It has a wingspan of and weighs . Deve ...

Newcastle University Newcastle University (legally the University of Newcastle upon Tyne) is a UK public university, public research university based in Newcastle upon Tyne, North East England. It has overseas campuses in Singapore and Malaysia. The university is ...

. Boeing was awarded an $89 million contract by

DARPA The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military. Originally known as the Adv ...

's Vulture program, with Boeing covering the remainder. It was slated to make its first flight in 2014, but in 2012 the SolarEagle project was cancelled and

's Vulture program was refocused on advancing

photovoltaic Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially us ...

and

energy storage Energy storage is the capture of energy produced at one time for use at a later time to reduce imbalances between energy demand and energy production. A device that stores energy is generally called an accumulator or battery. Energy comes in ...

technologies.

References

Unmanned aerial vehicles of the United States SolarEagle Solar-powered aircraft 2010s United States military reconnaissance aircraft High-altitude and long endurance aircraft Propeller aircraft Cancelled military aircraft projects of the United States {{UAV-stub