FAA Flight Instructor Airplane (FIA)Weather and Weather ServicesHard
A pilot is on final approach when the aircraft encounters an increasing headwind that suddenly reverses to a strong tailwind accompanied by a severe downdraft. This scenario is characteristic of which hazard?
- AA steady crosswind component with no vertical shear
- BA microburst encounter during approach
- CClear air turbulence associated with the jet stream
- DStandard density altitude performance loss
Show answer & explanationAnswer & explanation
Correct answer: B. A microburst encounter during approach
A microburst produces a classic sequence: an increasing headwind (performance-increasing shear) followed by a strong downdraft and then a rapidly increasing tailwind (performance-decreasing shear) as the aircraft passes through the core and exits the far side of the outflow, often resulting in a dangerous loss of airspeed and altitude close to the ground.
Why the other options are wrong
- A. A crosswind alone does not include the vertical downdraft and headwind/tailwind reversal described.
- C. Clear air turbulence is associated with high-altitude jet stream shear, not low-level approach wind shear.
- D. Density altitude affects performance but does not create sudden wind reversals or downdrafts.
Microburst Wind Shear
A microburst is a small, intense downdraft that spreads out at the surface, producing headwind-to-tailwind shifts and severe altitude/airspeed loss for aircraft on approach or departure.
- Downdrafts can exceed 6,000 feet per minute
- Horizontal extent typically 1–2.5 nautical miles in diameter
- Duration usually 5–15 minutes
- Sequence: increasing headwind, then severe downdraft, then increasing tailwind
Memory trick: Headwind up, downdraft slams, tailwind grabs — the microburst trap.