Location
Floor 13 of the car park now appears to be classed as a designated viewing area with the aviation hobby shop and a small cafe situated on the roof of the Terminal 1 short stay car park. It offers reasonable views of the international pier on Terminal 1 and Terminal 2. However other parts of the airport are restricted (especially Terminal 3 British Airways Domestic). Photography is OK but with two potential problems: There are fences around with a only a few holes at certain points from which to take photos and only aircraft using Terminal 2 and certain stands on Terminal 1 can be photographed without obstructions. With the car park charges it is also the most expensive spot at Manchester.
Hope that helps you Ollie 😎