Parallel or Crossing Runways
During takeoff and landing, an aircraft's wake sinks toward the ground and moves laterally away from the runway when the wind is calm. A 3 to 5 knot crosswind will tend to keep the upwind side of the wake in the runway area and may cause the downwind side to drift toward another runway. Since the wingtip vortices exist at the outer edge of an airplane's wake, this can be dangerous.
Read more about this topic: Wake Turbulence
Famous quotes containing the words parallel and/or crossing:
“There isn’t a Parallel of Latitude but thinks it would have been the Equator if it had had its rights.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“This, my first [bicycle] had an intrinsic beauty. And it opened for me an era of all but flying, which roads emptily crossing the airy, gold-gorsy Common enhanced. Nothing since has equalled that birdlike freedom.”
—Elizabeth Bowen (1899–1973)