https://ghostarchive.org/archive/kyqWG
At least five drone shows have been canceled, or have paused the use of the systems, after several drones struck a crowd at a holiday show in Orlando on December 21.
Universal Orlando, Orlando World Center Marriott, the cities of Dallas and Austin, Texas, and a New Year’s Eve event in New York City’s Central Park have either canceled drone shows or the drone components of larger holiday events following the incident.
It is unclear which companies were under contract to produce the shows in each location.
Footage captured on December 21shows drones colliding with each other before falling from the sky during a holiday show at Lake Eola Park. Some drones fell into the lake, some onto the ground and some into areas where a crowd was watching.
Among them was a 7-year-old boy who was struck in his chest by one of the drones. He underwent emergency heart surgery, according to a GoFundMe campaign posted by his family, who spent Christmas in the hospital as he recovered. CNN has reached out to his family for an update on his condition.
The videoshowed several red and green drones crashing into one another before hitting the ground, in what the city described as “technical difficulties,” following the incident.
because Quads (and more-numerous rotor systems), don’t use a variable pitch rotor, and the rotors are directly connected to the motors. Attitude is controlled during powered flight by spinning up or down specific rotors. To roll starboard, you sped up the port-side rotors and slow down the starboard. Yaw, conversely speeds up the two rotors that are spinning the same way and slows down the other two, creating a torquing moment.
Without power, you have no control, and it will generally turn to fall with least resistance.
This is opposed to helicopters which have a swashplate allowing the rotor’s pitch to be changed as it spins around. (you have to sets of controlls, ‘cyclic’ which alters the pitch over specifc points in its’ rotation; and ‘collective’ which adjusts over all pitch.)
Even from a hover, you can autorotate into a forward glide (and this dramatically increases lift production), and more importantly, can build up energy in the rotor system letting you briefly come to a hover just before you, uh. not-quite-crash.
It should be noted, that the sole reason we’re using quads for these systems is because they’re cheap. Collective pitch helicopters are more complicated to build, and more expensive to maintain. They’re less energy efficient, their control inputs exhibit significantly more lag, and they’re even more unstable than helicopters (whose single rotor provides a significant amount of gyroscopic stabilization.)
The only reason unskilled people can fly quads at all (or even modestly skilled people…) is because of the shitloads of flight stabilization routines running on them. If you add the cyclic control you’d need to change that, then they’d be significantly more expensive and complicated.