http://www.gizmag.com The benefits of using hydrogen fuel cells to power UAVs have been shown by the Naval Research Laboratory (NRL) with its Ion Tiger UAV setting an unofficial flight endurance record of 26 hours and 1 minute while carrying a 5-pound payload. While taking advantage of hydrogen as a high-energy fuel, the electric fuel cell propulsion system onboard the Ion Tiger also boasts the low noise and signature of a battery-powered UAV.en gizmag.com http://www.gizmag.com/ion-tiger-uav-endurance-record/13487/#comment-11125 http://www.gizmag.com/ion-tiger-uav-endurance-record/13487/#comment-11125 Tue, 01 Dec 2009 14:23:55 -0600