What time frame does O'Hare Airport maintain for operations?

O'Hare Airport operates 24 hours a day, which allows it to accommodate a wide range of flight schedules and adapt to varying travel demands. This continuous operation is crucial for a busy hub like O'Hare, where international and domestic flights need to be scheduled at all hours to meet passenger needs. Operating around the clock supports both airlines and travelers, ensuring connectivity and flexibility, especially in troublesome weather conditions or unforeseen delays that may occur regardless of the time of day.

The other options suggest limitations on operational hours, which do not reflect the continuous nature of O'Hare’s service. Limited hours of operation or only being open during peak travel times would hinder the airport’s ability to function as a major transit point. Furthermore, opening only for scheduled flight times would not align with the operational model that serves multiple airlines and provides a 24-hour service environment.