In the movie, Elastigirl says: "Island approach, India-Golf-Niner-Niner checking in." She also says, "VFR on top," "Angels 10," "track east," "transmitting in the blind guard," and "buddy-spiked."
It's actually real U.S. Air Force lingo that indicates her plane number ("IG99"), that she's obeying visual flight rules ("VFR"), her altitude (10,000 feet), her flight direction (east), that she's making an emergency call and hasn't confirmed communication, and that she's a friendly aircraft and shouldn't be fired on. Whew! Got all that?
Elastigirl is even more brilliant than we thought!