Assembly, computer program product and method for displaying navigation performance based flight path deviation information

A navigation performance based flight path deviation display assembly includes a display and a display processor capable of generating an image upon the display. The image includes at least one flight path scale comprising a reference point bounded by end markers extending in at least one of a lateral and vertical direction. The display also includes at least one moveable deviation pointer disposed on the flight path scales. Additionally, the image includes a representation of at least one extendable navigation error disposed on the flight path scale, and extending from at least one of the end markers toward the reference point based upon an actual navigation performance (ANP) and the RNP for the aircraft. The image may also include at least one moveable intersecting flight path pointer disposed on the flight path scales.