Marvel Comics continuity
While at Memphis Airport for reasons unknown, Shockwave was ambushed by his rival Megatron. The two battled on the tarmac, destroying several planes and causing several flights to be cancelled. The seemingly-unshaken air traffic controllers began placing bets on the outcome of the fight. Starscream observed the battle from the air, and reported the incident to Earthforce.
Upon the arrival of the Autobots, the two feuding leaders realized that they had been manipulated into battle as part of an elaborate plan to usurp both of them from the leadership of their respective Decepticon splinter factions. The two put aside their differences and departed Memphis to find their betrayers.
- Memphis at Wikipedia