I think that's to do with the wake/vortices a helicopter creates. Apparently, the effect is so strong that it can affect lift in a fairly large area over a few minutes. There's a recent case where a light plane took off in the neighborhood of a heli that just landed, and it veers off course, and hits the heli.
replyThats thats just one part of the problem of flying machines.
replyPlanes also require an enormous amount of space and time between local movements at airports. City street are the same as airports, space or should i say TIME is needed betwee aircraft. Airports have been runing for over 50 years, they never run planes back to back.
Remember one mistake, one crqsh between two flying cars, and both are basically dead.