Separate aircraft departing an intersecting runway behind a Category B or D departure by ___ minute(s) if projected flight paths will cross.

• A. 2
• B. 1
• C. 3
• D. 4

Answer: (A)

When two runways intersect and the projected departure paths will cross, you must enforce a time-based separation to keep the crossing area clear for safety. For Category B or D departures, the minimum behind such a departure is two minutes. This two-minute spacing gives enough time for the first aircraft to climb out and clear the intersection before the second aircraft reaches that crossing point, reducing the risk of conflict or wake effects as the paths converge. Shorter intervals, like one minute, could leave insufficient room for clearance, while longer intervals would unnecessarily reduce throughput without additional safety benefit for these categories.