I'm not sure bee's can hear, but they can feel vibration. What happened to the copter had nothing to do with vibration.
When bee's leave with a new queen, to start a new nest, they can fly for miles, hundreds of feet high.
What got your copter was......pheromones
If you cut one bee with your blades, the body parts of that dead bee give off a pheromone that tells the rest of the hive (swarm) "we have been attacked" and they go into defensive mode. Since the only thing around was your copter, they attacked it. As your copter sliced and diced more bee's, the pheromone scent got stronger and more attacked you copter.
Hope this explains it... Great video though.
When bee's leave with a new queen, to start a new nest, they can fly for miles, hundreds of feet high.
What got your copter was......pheromones
If you cut one bee with your blades, the body parts of that dead bee give off a pheromone that tells the rest of the hive (swarm) "we have been attacked" and they go into defensive mode. Since the only thing around was your copter, they attacked it. As your copter sliced and diced more bee's, the pheromone scent got stronger and more attacked you copter.
Hope this explains it... Great video though.