Directory of U.S. Military Rockets and Missiles
Appendix 2: Modern UAVs
Copyright © 2024 Andreas Parsch

AeroVironment RQ-22 Global Observer

The RQ-22 Global Observer was an experimental high-altitude very-long-endurance surveillance UAV.

The Global Observer program had its origins in 2005, when AeroVironment flew its "Odyssey" drone, a medium-sized very light-weight long endurance vehicle with hydrogen fuel cells powering the electric engines of 8 propellers. In 2007, the Global Observer Joint Capabilities Technology Demonstration (JCTD) started, sponsored by the Departments of Homeland Security and Defense and various military services, incl. the Special Operations Command, Air Force and Army. The goal was to develop a very-long-endurance UAV to cover gaps in the services' ISR (Intelligence, Surveillance and Reconnaissance) and communications relay capabilities. For this demonstration, AeroVironment received a contract to build and fly two air vehicles. Flight tests would be performed at the Air Force Flight Test Center at Edwards AFB.

AeroVironment's Global Observer UAV was a very large aircraft, built from light-weight composite materials. The propulsion system ran on liquid-hydrogen powered fuel cells, which provided the electric power for the aircraft's systems as well as the 4 engines driving the wing-mounted propellers. Maximum flight duration was expected to be at least 5 days at high altitude, with a payload weighing up to 172 kg (380 lb) and a power requirement of up to 2.8 kW. The envisioned mission options included satellite-like communcations relay, disaster response and maritime surveillance.

Photo: NASA

The first flight of the first air vehicle (GO-1) occurred on 5 August 2010. The flight was limited to 1200 m (4000 ft) altitude, and used battery power only. When low-altitude testing had been completed, the hydrogen-fueled power supply was installed and ground-tested. In January 2011, the aircraft made its first flight on hydrogen power. Later that year, the official designation XRQ-22A was assigned by the USAF to the Global Observer UAV. On 1 April 2011, the GO-1 vehicle crashed 18 hours into its test flight, bringing the test program to a halt. In December 2012, the DoD terminated the contract with AeroVironment, main reason being the crash of GO-1 and the subsequent loss of commitment from the main sponsors of the JCTD. At the time of the crash, the second XRQ-22A (vehicle GO-2) was almost completed, but in the end it was never taken up by the Air Force.


Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for XRQ-22A:

Length21 m (70 ft)
Wingspan53 m (175 ft)
Ceiling20000 mm (65000 ft)
Endurance5-7 days
PropulsionLiquid hydrogen powered combustion engine driving four electric motors

Main Sources

[1] Wikipedia: AeroVironment Global Observer
[2] AeroVironment Inc. Press Releases

Back to Directory of U.S. Military Rockets and Missiles, Appendix 2

Last Updated: 11 January 2024