Keeping these operations away from the main public space also gives the terminal the greatest amount of flexibility. Within a three-level terminal, for example, you can vertically separate the mechanical rooms on the ground floor, place them at the core of the building and then leave the rest of the terminal to open out into the flexible, sunlit large spaces. For example, some carriers only operate one or two flights a day from their gates. The system even issues requests for scheduled maintenance work and it also notifies technicians about worn-out parts and sudden repair needs. This feature is important for operational efficiency and economy.
Airlines can also expand and contract their operations during the day and over the years.
As officials at Denver's new airport can attest, baggage is one of the most complex, space-intensive systems in any terminal. The automated equipment and baggage corridors consume large amounts of space so that passengers' luggage can travel from ticket counters to the baggage rooms and finally to the tarmac. The baggage system must also have large continuous interstitial corridors that carry the luggage from one location to another and provide easy access for maintenance, repairs and upgrades. As in the rest of the terminal, flexibility is essential to baggage system design. Initially, the terminal may have a baggage zone where each airline uses its own equipment.