A drone is only as useful as its power supply. Internal combustion engines are powerful but loud. Batteries can only sustain short flights, and are drained even faster if the drone has to carry any additional payload.
But on May 6, a Russian firm announced it was bringing a Gjis UAV, a drone powered by hydrogen fuel cells, to the massive Army-2019 exposition in June. Though not without risk, if the fuel cell drone works at promise it could pack a surprising amount of capability into its small frame.
Made by International Aero Navigation Systems Concern, the Gjis drone boasts an altitude ceiling of at least 9,800 feet, a 3 mile operational radius, and a cruising speed of over 35 mph.
“The advantage in using hydrogen-powered UAV is that it can operate without additional logistics or fuel infrastructure — the users simply pour water into fuel cartridge, and the resulting reaction releases hydrogen that can power this UAV for several hours,” said Samuel Bendett, an adviser at the Center for Naval Analyses. “Given its range, this could be a close/support UAV.”
The phrase "without additional logistics” does not mean without additional risk. The design uses a metal hydride cartridge in the fuel cell. If that cartridge uses sodium borohydride with impurities, during hydrolysis it can off-gas borohydride-dibrone, which is a skin irritant. Dibrone by itself is both toxic when inhaled and also highly flammable.
That would be a lot of risk for increased range alone, but the drone doesn’t just provide longer range. The fuel cell on the drone offers 3 hours of flight time, about six to nine times as long a flight duration as could be achieved by batteries instead. It can also carry 22 pounds of payload as a baseline, and could carry more with additional fuel cells. For comparison, the standard hobbyist quadcopter can carry about 1 pound of payload.
“There have been reports that Russians may have tested hydrogen-powered UAVs in Syria,” said Bendett, a fellow in Russian studies at the Amrican Foreign Policy Council. “The Ministry of Defence is looking at a range of power options for its unmanned fleet - from diesel to electric to diesel-electric to now hydrogen-powered systems. These choices were informed by the Syrian experience, and the designer of Gjis is clearly hoping to get Ministry attention.”
Besides military interest, the hydrogen fuel cell drone may be marketed to the Interior Ministry or National Guard or any of Russia’s security agencies and departments interested in getting an ISR drone.
The risks with the fuel cell are real, though it’s easy to see the hazards spun as an advantage. A drone that catches fire when it crashes is a drone that might make opposing forces think twice about bringing it in with a net.