For all those getting excited about the air activities around Tucson check out what units are based there and their roles.
355th Fighter Wing with A-10s
55th Electronic Combat Group flying electronic recon/warfare planes.
Finally there is AMARG - Aerospace Maintenance and Regeneration Group the biggest plane boneyard in the US. Many different types fly in and out for storage & maintenance.
There are also a number of other units at this base. Chances are that the A-10 & electronic SIGINT/Recon planes are just training.