Which term refers to a 24-hour period that starts at 0001 local time and ends at 2400 local time?

• A. Calendar Day
• B. Bank
• C. Bulkhead
• D. Configuration

Answer: (A)

The main idea here is the calendar day. In aviation and daily operations, a calendar day is the 24-hour span defined by civil dates in local time, starting at 0001 and ending at 2400. This aligns with the local date you see on clocks and schedules, and it’s the boundary used for logging flights, crew duties, and rest periods. It’s different from other terms that refer to physical or logistical concepts—like a bulkhead (a cabin wall) or a seating configuration (how seats are arranged)—or a bank (a financial or resource grouping). Those don’t denote a 24-hour period, whereas the calendar day specifically describes that full day from the first minute to the last minute of the local date.