This report studies a practical problem related to the use of GPS/INS technology for sensor direct georeferencing. It is a case study of a specific, yet typical, situation whre the performance of a GPS/INS was pronounced unsatisfactory for orientation of an airborne sensor. However, it was in fact not the poor quality of the navigation data but rather numerous disregards occurring in the flight execution and data treatment that have led to this wrong conclusion. The presented analysis reveals the errors committed at different stages of data treatment and quantifies their impact on the sensor exterior orientation. It also explains the remedies employed to mitigate their impact. The recommended procedures are drafted in a summary.