On late Saturday morning, a bird flew out of the cold Detroit sky, across an airfield and into the cockpit of a jetliner bound south for Atlanta. Some believe it was a sparrow. Some, a hummingbird. A Delta Air Lines spokesman referred to it only as “stowaway” – and in any case it would be a long delay before anyone on Flight 1943 could catch the thing to get a look at it. Shane Perry, a minister with a connection and a speech to make, was waiting to board when he saw the pilot walk off the jet bridge and whisper something to the ticket agent. “He said, ‘In my 18 years of doing this, this is the first time I’ve ever seen this,’ ” Perry told The Washington Post.