In the post-war era , as the German developments became better known , a variety of research projects began to develop seekers based on the PbS sensor . These were combined with techniques developed during the war to improve accuracy of otherwise inherently inaccurate radar systems , especially the conical scanning system . One such system developed by the US Army Air Force ( USAAF ) , known as the " Sun Tracker " , was being used as a possible guidance system for an intercontinental ballistic missile . Testing this system led to the 1948 Lake Mead Boeing B-29 crash
1948 Lake Mead Boeing B-29 crash
1948 Lake Mead Boeing B-29 crash
Infrared homing