An aircraft angle of attack and sideslip angle indicator includes a display responsive to angle of attack and sideslip angle measurements from an angle of attack sensor and a sideslip angle sensor on an aircraft. The display depicts angle of attack along a first (preferably vertical) axis, and sideslip angle along a second (preferably horizontal) axis, with the axes intersecting at a display datum which represents acceptable angle of attack and sideslip angle values from the aircraft. The display depicts the aircraft's current angle of attack and sideslip angle with respect to the display datum, thereby indicating to the pilot whether non-optimal (and perhaps dangerous) flight conditions are occurring.