Safe zone for closely spaced parallel approaches

A study was conducted to introduce a method to structure the geometry of aircraft on approach to closely spaced parallel runways, such that a predetermined amount of time was available to respond to an alert. A zone for the trailing aircraft relative to the lead aircraft was computed such that the two aircraft was unable to pass within 500 feet of one another within a prescribed period of time in the event of a blunder while remaining clear of the wake vortices of the other aircraft. This method was a different and complementary approach to detect and resolve (DAR) methods, as it was used to softly constrain the geometry of the problem. The approach used simple aircraft kinematic equations to determine an expression for the minimum time to a lateral separation of 500 feet between the centers of mass of the aircraft. The solutions to the problem were also based on the existing speed of the two involved aircraft and assumed that no speed changes occurred during the encounter.