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