ASK TOM: Winds and aircraft landing/takeoff

Dear Tom,

Anyone living near O’Hare knows that the direction in which planes take off and land depends upon wind direction. Is wind direction more critical for takeoff or landing?

— Ryan Johnson, Chicago


Dear Ryan,

Retired United pilot Phil Rider told us that while there is no hard-and-fast rule, in general any cross wind component to the active runway is more critical for landing. He noted that limiting the amount of cross wind is even more important with low visibility or slick runways. Meteorologists use years of wind  data on direction and speed to determine the best runway orientation for a new airport. Chicago air traffic controllers frequently have to switch operations to northeast-southwest or east-west runways when the wind shift associated with the lake breeze reaches the city’s airports.