Drone crash to blame for a 52-acre grass fire in Colorado on Wednesday

BOULDER COUNTY, Colo. (KKTV) - The Boulder County Sheriff’s Office issued mandatory evacuations for a neighborhood on Wednesday as a grass fire burned.

The following message was sent out at about 3:25 p.m.:

“A Mandatory Evacuation Order has been issued for the area(s) of the 51st to 65th and Nelson to Neva due to a Wildland Fire. Take the following protective actions immediately: Evacuate Now. This Order stands Until Further Notice.”

At about 4:45 p.m. the sheriff’s office gave the “All Clear” for the neighborhood. The last estimated size of the fire was about 52 acres.

On Thursday, the sheriff’s office announced the cause of the blaze:

“On April 20, three researches associated with the University of Colorado-Boulder’s Aerospace Engineering Department were at the Table Mountain Radio Quiet Zone utilizing an Unmanned Aerial System (UAS), commonly referred to as a drone, to conduct severe weather studies.

While they were flying the fixed wing aircraft, it crashed at a high rate of speed into the ground causing a lithium ion battery cell to dislodge and ignite. The crew used an on-site fire extinguisher, but were unable to get the grass fire stopped before it began to quickly spread due to the high winds.

The crew remained on-scene and fully cooperated with investigators. They were flying within regulations and within the flying capability of the craft. No criminal charges will be filed due to the accidental nature of the incident.”

The neighborhood is northeast of Boulder near Clover Basin Reservoir.