Air cargo ramps vary considerably more in relation to cargo volumes than buildings, and, in part, are a function of available land and the airport layout. Due to the variability among airports, the best approach to determining aircraft ramp requirements appears to be an average-day/peak-hour methodology. This approach to assessing capacity involves examination of the ramp chart for the most recent periods. When specific gates/parking positions are not occupied, there may be time slots available to accommodate additional aircraft, depending on the ramp use strategy at the airport. Typical turnaround times at airports that do not serve as cargo hubs for cargo aircraft (i.e., Memphis, Louisville) are longer than for passenger aircraft, which results in a greater requirement for parking positions.