Abstract: A method and apparatus for sensing the profile and position of a well component in a well bore and transmitting this information to a surface mounted display unit to aid an operator in performing subsea well operations. The apparatus includes an instrumented flange with appropriate end connections to allow connecting the flange between the annular preventer and the drilling riser. The instrumented flange is sufficiently long to allow a first plurality of sensor units to be arranged circumferentially around the axial bore of the flange in a single plane and a second plurality of sensor units to be arranged in a helical pattern along the axis of the flange. The output signals of the sensor units are processed at a signal processing unit which then transmits the information to a display unit at the surface.