Definition
Standardized separation rules and pilot/controller actions used to keep aircraft clear of the rotating, descending vortices generated behind larger aircraft. These procedures specify minimum spacing distances and times, altitude offsets, and visual avoidance techniques applied during takeoff, approach, landing, and en route operations behind heavier traffic.
Plain English
The rules that keep your aircraft safely away from the invisible whirlpools of disturbed air left behind by bigger aircraft. They tell you how far behind to stay, how long to wait, and where to fly to avoid getting caught in that rolling air.
Context Anchor
Seen in instrument approach procedures, especially when aircraft are arriving close together or using nearby parallel runways.
Derivation
‘Wake’ comes from Old Norse vǫk, meaning the track or trail left behind something moving through water. Boats leave a visible wake on the surface; aircraft leave an invisible wake in the air. ‘Turbulence’ is from Latin turbulentus, meaning ‘full of commotion or disturbance.’ Together the term names the disturbed, churning air left in an aircraft’s trail.
Why Pilots Care
Failure to follow these procedures can result in sudden roll or loss of control authority near the ground.
Analogy
It is like the rough water behind a boat. Another boat crossing that trail may rock hard even though the water ahead looks calm.
Intuition Check
Do not think of wake as only meaning being awake. Here, wake means the trail left behind a moving aircraft. Do not think these procedures are just suggestions. They are safety steps used to avoid dangerous disturbed air.
Example Sentence 1
Tower applied wake turbulence procedures and held the small Cessna on the runway for two extra minutes after the 757 departed.
Example Sentence 2
ATC issued a speed adjustment to maintain the required wake turbulence procedures during the paired ILS approaches.