Encroachment, encroachment, encroachment
Click to see maps of the areas surrounding Tucson International Airport (TIA) and Davis-Monthan (DM) AFB. Note the amount of encroachment around both of these airport facilities. Due to their location less than 5 miles apart, the FAA had to grant a special waiver. Much of the area to southeast of Davis-Monthan is State Trust Land that can be sold and developed in the future.