The rules defining the phraseology to be used between pilots and air traffic controller are strigent and well defined. But sometimes we hear strange things on the radio, in both very relaxed and very tense situations…

A quite famous one reportedly happened in Frankfurt:

Allegedly the German air controllers at Frankfurt Airport are renowned as a short-tempered lot. They, it is alleged, not only expect one to know one’s gate parking location, but how to get there without any assistance from them. So it was with some amusement that we (a Pan Am 747) listened to the following exchange between Frankfurt ground control and a British Airways 747, call sign Speedbird 206.
Speedbird 206: “Frankfurt, Speedbird 206 clear of active runway.”
Ground: “Speedbird 206. Taxi to gate Alpha One-Seven.” The BA 747 pulled onto the main taxiway and slowed to a stop.
Ground: “Speedbird, do you not know where you are going?”
Speedbird 206: “Stand by, Ground, I’m looking up our gate location now.”
Ground (with quite arrogant impatience): “Speedbird 206, have you not been to Frankfurt before?”
Speedbird 206 (coolly): “Yes, twice in 1944, but it was dark,… and I didn’t land.”

Some of the best ATC jokes also involve student pilots, or private pilots with less experience:

A controller at the Nashville, Tennessee airport told me about an incident from several years ago when he cleared a Cessna 172 (4 seater small aircraft) for landing. As the Cessna turned to final approach, an airliner called in ‘over the marker’ (5 miles from the airport). The Cessna was about a half mile from the runway, and the controller knew he could land and clear the runway well before the airliner would land, so he cleared the airliner to land as well. A few seconds later, the Cessna pilot asked the controller, “How far behind me is that 737?” Before the controller could respond, the airline pilot keyed his mike, and in a deep bass voice said, “Don’t look back!…”

The two ones above are extracted from the Funny Air Traffic Control Quotes from businessballs.com, which contains much more, and is updated frequently.

But now, very special Hat Tip to Aviatrix, from Cockpit Conversation, for reporting and publishing this one in one of her latest posts:

STL approach: “United XXX best forward speed to the marker, you’re number one.”
United XXX (male): “Roger, balls to the wall.”
STL approach: “American XXXX, you’re number two behind a 737, follow him, cleared visual, best forward speed.”
American XXXX (female): “Well I can’t do ‘balls to the wall’ but I can go ‘wide open’.”
-Radio silence-
Unknown Pilot (male): “Is American hiring?”

Sorry… well, not really