Cancun is a popular holiday destination and there are often a lot of requests about places to spot at the airport. Therefore we have this comprehensive guide which comes courtesy of a businessman who regularly visits Cancun, with additional information from Mike Nelson and Mark Birchenough.
Before going on holiday to Mexico, I sought the advice of a number of people on spotting at Cancun. Back in 2000 when I first visited Cancun, there were one or two places inside the terminal which could be used for spotting. Everything could be seen as long as it moved, because everything took off and landed on the one runway. I again visited in 2006, not long after the hurricane which devastated the whole area, but I did not have the opportunity for any extensive spotting except on departure. Since then the airport has changed substantially, particularly with the addition of the new runway.
I set out below the current situation based on information I have received from others, together with my own observations:

Finally, choose a right hand window seat for departure as you will either taxi past or take off past Terminal 2 and its satellite, then the GA Terminal, next Terminal 1 – they still park some aircraft on the ramp there – and finally the remote parking area halfway to the threshold with several derelict aircraft.