Why is there a helicopter flying over Arkham City?
There is a helicopter flying over Arkham City. What is the purpose of it?
It is also possible to grapple on it. Will I ever need this helicopter in my missions in the game?
Solution 1:
The Tyger helicopters are there for Tyger to keep control of the city.
When Protocol 10 is enacted, their purpose will be clear. Batman will have to hang onto the correct one to get a MacGuffin to advance the plot.