The FAA published updates to the wake turbulence separation categories on October 22 for Louisville, Miami, Cincinnati, San Francisco, Atlanta and Philadelphia airports based on improved understanding of how wake vortices behave. Categories are now based on weight, certified approach speed and wing characteristics. Special consideration will be given to aircraft with limited ability to counteract adverse rolls.
The new standards will be of particular importance to pilots when visual separation is applied at these airports.
The wake turbulence recategorization places aircraft into six categories rather than the current five for both departure and arrival separation. In some cases, such as a heavy jet (more than 300,000 pounds) following another heavy, separation has been reduced to three miles from four on final approach. In some other categories, such as most light business jets, however, wake turbulence separation was increased.