What is the minimum separation, in time, for a BE36 departing behind an MD11?

• A. 1 minute
• B. 2 minutes
• C. 3 minutes
• D. 4 minutes

Answer: (B)

Minimum time separation to avoid wake turbulence when a light aircraft departs after a heavy jet.

Wake turbulence from a heavy aircraft lingers and can affect a following light aircraft as it uses the same takeoff path. The BE36, being a light aircraft, is more susceptible to being disturbed by those vortices. Allowing about two minutes gives the vortices time to move away from the runway and dissipate enough so the lighter airplane won’t encounter dangerous wake. This is the typical minimum under standard conditions for a light aircraft departing after a heavy jet like an MD11.

In practice, if winds are strong or crosswind, or conditions are unusual, more separation may be needed, but two minutes is the baseline spacing to reduce wake turbulence risk.