A method of calculating a climb-dive marker (CDM) that is visibly present on a display even as the aircraft approaches a roll angle of +/−90° is provided. An exemplary CDM method comprises obtaining, an X-axis velocity, a Y-axis velocity, and a Z-axis velocity in aircraft body coordinates of an aircraft; calculating a CDM elevation; and displaying, by the controller, the calculated CDM elevation. The method can further comprise obtaining an angle of attack (AoA) of the aircraft and a roll angle of the aircraft, wherein the AoA is set as the value of the CDM elevation when the roll angle is within a preset range. The CDM elevation may also be calculated using a combination of the AOA and the CDM formula when roll angle is within a second preset range.