In radar operations, exact minimum course divergence for parallel runway departures released simultaneously is what?

• A. 15 degrees
• B. 10 degrees
• C. 20 degrees
• D. 25 degrees

Answer: (A)

When two aircraft on parallel runways depart at the same time, radar control relies on a definite angular difference between their flight paths to maintain safe lateral separation. This course divergence is the angle between the two tracks as they diverge away from the runways. The exact minimum required for this scenario is 15 degrees. This value provides a reliable margin against small navigation errors, wind effects, or radar position inaccuracies, because the tracks separate steadily as distance increases. A smaller divergence could allow their paths to come closer than the safe separation threshold, while larger divergences aren’t necessary to meet the safety standard. Therefore, 15 degrees is the correct minimum.