How close together do runways need to be for ATC to issue a sidestep?

• A. 1200 ft
• B. 1000 ft
• C. 2000 ft
• D. 800 ft

Answer: (A)

Sidestep is used when parallel runways are close enough that independent approaches aren’t guaranteed, so ATC can direct one aircraft to move laterally onto the adjacent runway to maintain safe separation during final. The minimum centerline separation that allows this maneuver is 1,200 feet. This spacing provides enough lateral clearance and turning radius for a controlled sidestep onto the other runway without encroaching on the other aircraft’s path. Distances smaller than that (800 ft or 1,000 ft) don’t give enough room to execute the maneuver safely, while a larger spacing (like 2,000 ft) is not the required minimum.