AAL210, an MD81, departs Runway 28R from the approach end. N10FD, a FA20, is waiting to depart Runway 28R at Charlie. What is the required wake turbulence separation?

• A. 1 minute
• B. 2 minutes
• C. 3 minutes
• D. No wake turbulence separation is required

Answer: (D)

Wake turbulence separation is about protecting a following aircraft from the wake of the preceding one, and the need for it depends on the lead’s weight and whether their paths overlap in time and space.

In this scenario, the MD-80 family aircraft is already departed from the approach end of Runway 28R and is airborne. The FA20 is waiting to depart Runway 28R at Charlie, which is an intersecting point along the same runway. Once the MD-80 has cleared the intersection and its wake has dissipated, the following aircraft will not be in the path of any lingering wake. Therefore no additional wake turbulence separation is required. If the follower were directly behind in the same takeoff path with wake still present, separation would be needed, but that isn’t the case here.