What is the basic radar separation between successive IFR departures?

• A. 5 NM
• B. 2 NM
• C. 4 NM
• D. 3 NM

Answer: (D)

Basic radar separation is the minimum horizontal distance required between two aircraft being observed on radar. For successive IFR departures, the standard spacing is three nautical miles. This separation gives enough room to account for typical differences in climb rates, speeds, and potential track adjustments, while still allowing the radar controller to monitor both aircraft reliably and avoid conflicts as the first aircraft climbs away and the second follows. In practice, controllers ensure at least this distance before allowing the second aircraft to proceed on a similar path, sometimes adjusting speed or delaying departures to maintain the spacing. The other options don’t reflect the common standard for this situation: five miles is a broader en route separation, while two or four miles would not meet the established basic separation for successive departures.