DENVER -- Colorado's drone mystery continues and descriptions of drone sightings on the eastern Plains are offering a few clues about what may be occurring.
Some have described the drones as having rotors. Others say they resemble small planes. Both may be correct. There are multi-rotor drones and fixed-wing drones.
"An aircraft like this (fixed wing) can fly for three to four hours with the same battery. A multi-rotor can only for about 30 minutes," explained Eric Frew, a professor in the Aerospace Engineering Sciences Department at the University of Colorado Boulder.
CU Boulder is at the cutting edge of research into drone swarming technology, which is what we may be seeing out on the eastern Plains.
"It sounds like they're using similar types of software and similar types of algorithms," Frew said.
Swarming is the ability to fly several dozen drones with just one pilot, and CU Boulder was one of the first entities in the country to receive a waiver from the FAA to do it legally.
"Having one pilot command three drones is no less safe than one pilot commanding one," said Frew.
Students at the University of Colorado Boulder are testing drone swarming technology to improve search and rescues. Swarms of drones could help teams more quickly find lost hikers or someone buried in an avalanche.
The university has also looked at how drone swarms could be used to track wildlife.
Swarming could explain why folks on the eastern Plains are seeing so many drones, but there is no large gathering of pilots.
"The thing I find most surprising is the night-time flying. Why at night? I think it implies they don't want to be seen. I think it's just because they don't have permission to fly 20 at once and they want to try it out," said Frew.
However, the mystery of who is doing it and why they are flying swarms of drones at night remains a mystery.
"I'm hoping we as a community will help solve this problem and citizens will see we care about answering these questions too. The people flying these drones are giving us a bad name," said Frew.