Dropping Fire Retardants by Helicopter and Its Application to Wildfire Prevention near Electrical Transmission Lines

Dropping fire retardants by helicopter can effectively reduce the intensity of wildfires. This study proposes a test plan for spraying different from bucket extinguisher. In this study, pure water, 10% Class AB flame retardant, 0.3% gel A and retardant + 0.6% guar gum were each added to extinguishing device sprayed on 4-layer, 6-layer, 12-layer wood cribs. The radiation intensity, mass loss, temperature used as indicators compare burning field difference in combustion after cribs ignited 1 h natural air drying. results showed that retardancy could be ranked high low follows: > water. During long-term drought period Hunan Province, China, August September 2022, application dropping reduced wildfires avoided transmission line trips due wildfire, which number ground personnel required when fighting large-scale forest fires.