Most drones today use internal
combustion engines that are extremely loud, which forces officials to
fly them at higher altitudes during missions.
about lawnmowers or chainsaws -- they're really loud," Naval
Research Lab researcher Karen Swider-Lyons told LiveScience
during a recent interview. "It's hard to spy on people
when they know you're there, so you had to fly them at high altitudes
to keep them from being heard."
The Office of Naval
Research said spy planes powered by electric engines are available,
but they have shorter estimated flight times than aircraft powered by
internal combustion engines.
To help fill a void in next-gen
technology, the "Ion Tiger" UAV is powered by hydrogen fuel
cells. The engines can run quieter than a regular engine, while
also being twice as efficient, offering an appealing alternative as
increases the use of spy planes.
During testing in
October, Ion Tiger flew 23 hours and 17 minutes consecutively, though
that number was recently topped while flying over the "Aberdeen
Proving Ground." The 37-pound craft flew for 26 hours and
The military has announced different ways it looks
to go green, ranging
from hybrid Humvees to greener Navy ships -- but this is the
first significant proof showing a UAV successfully powered by
The newer drones could also fly civilian
routes to observe natural disasters, track storms, or provide
surveillance, military experts said.