THE MAIN ROTOR BLADES ARE TRAVELING AT HIGH VELOCITY AND CAN KILL OR MAIM YOU. BE VERY CAREFUL.
When I first stared flying helicopters, I read every single web page I could find on the Internet regarding helicopters. One web page mentioned a story where a guy was flying his helicopter in a park, and a little dog started chasing his helicopter around. The heli pilot asked the dog owner to retrieve his dog, but the dog owner thought it was cute and wouldn't do it. When the heli landed, the dog ran to the helicopter and lunged at it. The main rotor blades were still spinning at full speed and neatly chopped off the top of the dog's skull.
Also, there are stories about R/C helicopter rotor blades chopping off people's fingers. Don't believe it? Let's do the math.
An ECO 8 has a rotor diameter of 41.7 inches. This means the rotor tips travel 41.7 * 3.14 or 130.9 inches in one revolution.
The rotor is spinning at about 1600 rpm. This means the rotor tips travel 130.9 * 1600 or 209,440 inches in a minute.
In one hour the rotor tips will travel 60 * 209,440 or 12,566,400 inches.
12,566,400 inches/hr = 1,047,200 feet/hr = 198.3 mph!!!
So, when an ECO 8 rotor blade is spinning at 1600 rpm, the blade tips are traveling at 198 mph. That's why helicopter rotor blades can slice off fingers and the top of skulls.
RESPECT THE SPINNING ROTOR BLADES.