The unfun answer to collective nouns can be found in a pretty cool book by James Lipton, "An Exaltaion of Larks." It has over 1,000 group terms.

He has it listed as "A Hover of Flight Attendants."

And since someone will probably ask...he lists the collective noun for pilots as "A Flare of Pilots."

Also:

Stack of Planes
Odyssey of Luggage
Glacier of Baggage Handlers
Overload of Controllers
Racket of Helicopters
Postponement of Trains
Cancellation of Trains
Comedy of Airline Schedules