I agree with Bob when he says that laying queens can fly. I have seen it happen many times when a hive is disturbed. However I do not agree with his statement that the queen and she alone controls when the swarm leaves the hive. Maybe she does some of the time or even most of the time. I don't know. But I have seen a swarm issuing from an over crowded mini nuc. The swarm was in the air. The queen was on the board in front of the hive and she was most reluctant to go and was being chivvied, hustled and urged by the workers trying to get her to take off. I herded her with my fingers back in through the entrance and closed it with a piece of QE. The swarm returned within say 10 minutes and I was later able to remove the queen for use elsewhere and allow the bees to rear the single sealed Q cell in the nuc to replace her. In that case it was definitely the workers who were the dominant force behind the swarm and not the queen. Chris Slade