Dead Air

Dead Air is a campaign. The Survivors must make their way to a runway in hope of catching a plane away from the Infected.

Official description
Guide your team of Survivors out of the downtown core of Newburg's business district, through derelict office floors and still-inhabited cubicles, and out onto the runway of Metro International Airport, where the only thing standing between you and the last plane out of the city is a murderous army of the undead.

Writings on the wall
Several instances on the roof tops of dead often say "help need food" or S.O.S. There are also many writings about how a bomb will be dropped on the airport, only to find out that their predicitions were true as the survivors witness the runways nearly obliterated.