What is faster, the united airline bus shuttle or the airtran from terminal A to terminal C at Newark Airport? I am connecting a flight and the time is 1 hour. Both Airlines are United.
The bus is after security ("airside"), the Airtrain is before security ("landside").
As you're connecting between flights, you'll want to take the bus, as to use the train you will need to re-clear security.
1 hour should be plenty of time for that connection presuming your inbound flight is on time.