<Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> The Plane Train is an automated people mover (APM) at Hartsfield--Jackson Atlanta International Airport that transports passengers between the terminals and the airside concourses . The system is the world's most heavily traveled airport APM, with 64 million riders as of 2002 . </P> <P> The Plane Train opened along with the current airport terminal on September 21, 1980 . The system was jointly built by Westinghouse Electric and Adtranz, who supplied the system's initial fleet of C - 100 vehicles . The initial system consisted of the six stations from the terminal (now the Domestic Terminal) up to Concourse D . </P>

What is the plane train at atlanta airport