Experiments in aerial firefighting with and without additives and its application to suppress wildfires near electrical transmission lines

Abstract

A comparison scheme is proposed to extinguish non-uniform fire scenes and continuously uniform fire scenes using a helicopter’s bucket fire-extinguishing device to spray extinguishing agent. Pure water, and Class AB, gel, and Class A extinguishing agents were added to the bucket fire-extinguishing device to spray 4-layer, 6-layer, and 12-layer wood crib fires. It was discovered that the depth (the distance from the top of the wood crib) of effective cooling and prevention of temperature recovery by extinguishing agents was 0.36 m and that the cooling performance of the extinguishing agents in sequence from high to low was Class A extinguishing agent > gel extinguishing agent > Class AB extinguishing agent > pure water. Their capacity to prevent temperature recovery in the wood crib fires in sequence from high to low was gel extinguishing agent > Class A extinguishing agent > Class AB extinguishing agent > pure water. A device has been developed that can add extinguishing agent to the helicopter bucket efficiently, and its application on-site during the 2020–2021 Spring Festival and other events showed that it can quickly extinguish small-area wildfires near electrical transmission lines to reduce line trips due to wildfire.

Breakdown characteristics and influencing factors of live 500 kV insulators sprayed by extinguishing agents using helicopters

“…In recent years, Wuhan University, State Grid Hunan Electric Power Co., Ltd., Zhejiang University, and other units have carried out extensive research on the prevention and control of wildfire disasters on transmission lines, 2,7–10 mainly focusing on the tripping mechanism of transmission line wildfires, 7,8 manmade wildfire prediction, 9 wide-area satellite monitoring, 2 live fire extinguishing, 10 and other aspects, all of which play an important role in the prevention and control of transmission line wildfire disasters. Among the abovementioned prevention and control technologies and measures, fire extinguishment is the most effective means to avoid transmission line tripping.…”