While part of a Type 1 Strike Team in Shasta County, CA, we were assigned to handline construction on a slopover. After having completed approximately 2/3 of a mile of handline, we were in need of a few helicopter bucket drops to cool the burning brush in front of us so we could proceed. The fire was a backing fire, burning through the brush and timber litter. We received support from two helicopters. After each bucket drop, the fire would flare up where the downdrafts were the most severe. After the fourth drop, the open line experienced a rapid flare up with approximately 10 foot flame lengths that pushed over the line. The first 7 members at the head of the line retreated back up the line in a hasty fashion. Everyone else was at the top of the ridge and away from danger. No one was hurt, just a little shaken.

LESSONS LEARNED:
Always post a lookout. The erratic fire behavior was noticed and communicated multiple times to the remaining crew based on observations. Never underestimate the power of the downdrafts from helicopter operations. I thought that the copter was too high to have that much of an impact. I was wrong. Ensure escape routes are identified and known. Our retreat was back up the line we cut, but a congestion of personnel occurred when the information to retreat wasn't passed on down the line. Ensure all PPE is on and in place. Multiple personnel didn’t have their helmet shrouds on due to the heat of the day. Luckily no one was hurt.