Skip to content

Yukon-made sensors dropped from helicopter to collect wildfire information

The sensors were first tested in early August.
Fire Centre Officer Ashley Harris prepares to drop a Fire FROG sensor from a helicopter. (Yukon Protective Services/Facebook)

A made in the Yukon sensor solution got its baptism by fire collecting information on a blaze south of Pelly Crossing.

Three fire FROGS (forward rate of growth sensors) were dropped ahead of the Ta’tla Mun fire in early August to measure temperature and barometric pressure as the fire approaches. An announcement about the use of the new sensors said they offer real-time data on conditions at the head of an active fire front where it is normally too dangerous for firefighters to work.

The sensors were developed in partnership between Yukon Wildland Fire Management and Whitehorse-based Advanced Sensor Research Ltd. Yanik Freeman, one of the designers of the sensors said their core component is a computer board developed and manufactured in the Yukon.

Freeman said he was approached by Wildland Fire to modify the board for their purposes. He said the result is a device that can measure temperature and pressure with high accuracy. He said those measurements will be monitored in real-time from when the sensor is dropped from a helicopter until the fire consumes it. He said the prototypes have a transmission range of about a kilometre.

He noted that the Aug. 1 test of the devices was a historic first as there have only been tests of sensors on the ground in a prescribed burn setting, never on a real wildfire.

The FROGS have the potential to measure the spread of a fire when conditions make other techniques challenging. Ashley Harris, a Yukon fire centre officer, said fire spread is currently mapped by flying the fire’s perimeter with a GPS device or through satellite heat mapping.

“These methods work, but sometimes smoke can make flying a perimeter difficult while satellite data updates on a schedule. Fire FROGS provide real-time data; when it stops doing so, we can infer that the fire has spread past where the frog was dropped,” Harris said.

Harris said the Aug. 1 test of the sensors was designed to test the individual units and gather some initial data

The sensors dropped near the Ta’tla Mun fire were three of the 10 prototypes that Freeman and his collaborators built. Along with the temperature and pressure that the devices already measure, Freeman said upcoming prototypes will be fitted with equipment to measure humidity and air quality and may also be able to detect flames using infrared.

Harris said the information collected by the FROGS is operationally useful because it offers a look at the edge of a fire where it is unsafe for people to go directly. When combined with aerial observation, she said the data will be a powerful tool for the future of firefighting and fire science.

“This project definitely helps expand fire science in the Yukon, which helps us manage unpredictable fires more efficiently and strategically. In any given year, we monitor many fires that are far from human values that we allow to burn as part of the forest’s natural cycle,” Harris said.

“As a result, there are lots of chances to continue studying them. We are also lucky to have an engaged community that is really interested in fire. Between this and a recent Yukon University fire modelling project, it is clear that Yukon’s passion for fire science is only growing.”

With the concept of the airdropped sensors proven in the Aug. 1 test, Freeman said he would like to see the Yukon invention tested in other jurisdictions.

Contact Jim Elliot at

Jim Elliot

About the Author: Jim Elliot

I’m a B.C. transplant here in Whitehorse at The News telling stories about the Yukon's people, environment, and culture.
Read more