The US Navy has unveiled a new fuel cell-powered unmanned aerial vehicle that has improved its own endurance record by flying in the air for just over 48 hours.
The aircraft, named Ion Tiger and developed by researchers at the US Naval Research Laboratory, flew for 48 hours and 1 minute on April 16 and 18 by using liquid hydrogen fuel in a new cryogenic fuel storage tank and delivery system.
The flight broke the previous record of 26 hours and 2 minutes set in 2009 using the same vehicle, but with gaseous hydrogen stored at 5000 pounds per square inch (psi).
Keeping a drone in the air as long as possible represents a serious challenge to a drone operator, particularly in case of reconnaissance UAVs. Although long endurance is possible with conventional, hydrocarbon-fueled systems, they are usually loud, inefficient, and unreliable for spy drones.
Ion Tiger makes use of an electric engine, which is smaller and quieter.
Nevertheless, battery-powered systems are limited to endurances of only several hours.
To overcome this shortcoming, the aircraft uses hydrogen fuel cells to produce electricity, which improves the endurance trade-off.
Thousands of unmanned aerial vehicles could be buzzing US airspace by 2015 because of the FAA (Federal Aviation Administration) Modernization and Reform Act passed last year. The law requires the FAA to fully integrate unmanned aircraft into the National Airspace System by September 2015.
Additionally, it allows law enforcement agencies, including local police forces, to buy and use unmanned aircraft for evidence gathering and surveillance.
The law has however raised safety and privacy concerns among some lawmakers and advocacy groups.