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This improvement will explore concepts to recover lost capacity through reduced separation standards, increased applications of dependent and independent operations, enabled operations in lower visibility conditions, and changes in separation responsibility between Air Traffic Control (ATC) and the flight deck. OI 102141 Improve Parallel Runway operations

Notable example of a local advance that will see system-wide implementation: Recategorization (RECAT) of Federal Aviation Administration (FAA) Wake Turbulence Separation Categories at Memphis International Airport (MEM). The FAA currently uses six (6) wake turbulence separation categories based primarily on weight: Super (A380), Heavy, B757, Large, Small+, and Small. RECAT applies advances in knowledge of wake physics over the breadth of the current wake categories. Table 1 details the current FAA wake separation standards. The FAA recently approved a recategorization of wake turbulence separation minima from the current standard to a new standard (RECAT Phase I). This approval was based on years of joint research and development by the FAA, Eurocontrol, scientific experts in wake, and experts in safety and risk analysis. Categories are now based on weight, certificated approach speeds, wing characteristics, along with special consideration given to aircraft with limited ability to counteract adverse rolls. RECAT places aircraft into six (6) categories (labeled A-F) for both departure and arrival separation.

Potential hazard

  1. Impact of wake turbulence
  2. Runway incursions
  3. Near-mid-air collisions
  4. Complexity of taxi clearances
  5. Inadvertent crossing of a hold-line and/or entry onto an active runway (with or without loss of separation with an aircraft, vehicle or pedestrian),
  6. Takeoff / landing without clearance,
  7. Simultaneous takeoff and landing from the same or from intersecting runways, or,
  8. Takeoff / landing from/onto the wrong runway.

Corroborating sources and comments

FAA AVS Workplan for NextGen 2012, P. 66

Airbus Flight Operations Briefing Notes, Runway and Surface Operations, Preventing Runway Incursions;

RECAT of Wake Turbulence

The FAA Issues Notice To ATC Officials In Busiest Airports To Reduce Collision Hazards.

The Wall Street Journal (1/21, Pasztor, Subscription Publication) reports on an FAA initiative to reduce the risk of airborne collisions outside of some of the country’s busiest airports. Often the result of missed approaches and go-arounds, near-collisions are an issue previously highlighted by the NTSB after investigating previous incidents at the JFK, Las Vegas, and Charlotte airports. The altered landing and takeoff procedures, not spelled out in the article, are said to be taking effect at those airports as well as 13 others, including seven of the busiest 10 airports. The notice is said to apply to air traffic controllers at the affected sites and will apply to runways that are oriented in such a way that the extended center line of one runway intersects with another.

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