Google asked the US Federal Aviation Administration for permission to test a drone for monitoring and fighting fires. However, its drone plans, which were published Thursday in the federal register, have since been extinguished. 

The request came from Alphabet's Google Research Climate and Energy Group -- not the company's Wing subsidiary, whose drone delivery service was certified by the FAA in 2019. Wing drones are being used to deliver food and medicine during the coronavirus pandemic. 

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The Google Research group asked for permission to operate an unmanned aircraft system called the HSE-UAV M8A Pro, which weighs between 55 and 99 pounds. That drone, made by Homeland Surveillance & Electronics for agricultural purposes like spraying chemicals on crops, could in theory be filled with water to put out a fire, a Bloomberg report noted. 

Google, though, has "no immediate plans to reengage on this work," said a spokesperson on Wednesday, adding that the petition to the FAA was submitted "almost a year ago for a project we were considering exploring at the time."

Drones have been used in firefighting efforts for some years now, including during 2018's deadly Camp Fire in Paradise, California, where drone company DJI flew more than 500 drone missions in cooperation with Butte County to map the fire zone.