As historical background to 1959 Doppler radar navigation systems, an animated film considers the use of Ptolemy and Mercator's maps, the magnetic compass, and John Hadley's 1731 sextant. Clarence Rice, aviation products manager of the Bendix Radio Division in Baltimore, MD, points out that aviation navigation depends on knowing the ground speed and the path of the aircraft over the earth. He uses a chart to demonstrate the effects of winds on plane direction and the efforts to compensate: a homing device, which did not account for wind drift and also picked up static interference; the radio range system, which used four beams to overcome the drift problem but still received static; and the manual direction finder, which became the standard aid in the 1930s. A film describes how, in 1939, Bendix developed the automatic direction finder (ADF) with omnirange, which also eliminated static. Over the ocean, LORAN, or long range navigation, devices were used. Another animated film shows how Christian Doppler, in 1842, described the Doppler effect based on sound waves and how that principle has been applied to radar's radio waves. The film explains the "plus" Doppler effect for direct measurement of forward speeds and the "minus" for measurement of drift angle. Pitch and roll are also corrected by the radar beams since beam compensation is based on the magnitude of the Doppler shift. A plane's Doppler radar components include a transmitter, antennae, receiver, frequency tracker, and cockpit indicator. Mr. Rice explains how pilots divide their flights into shorter legs, placing the information into the navigational computer. He notes that Doppler radar will not become obsolete with faster aircraft speeds and that it does not require a land-based facility.

Lynn Poole opens the program with a brief history of radar. Dr. J.W. Gebhard, research psychologist with the Johns Hopkins Applied Physics Lab (APL), explains that his job is to improve the way men interpret radar pictures on an A-scope. He then demonstrates a PPI (plan position indicator) scope, which uses a bearing dial and cursor to locate a target. Dr. Albert Stone, a physicist with the APL, explains that RADAR is an acronym for "radio detection and ranging," which measures unknown distances accurately. He demonstrates radar's principles and explains how it works, including the radar antenna that indicates direction. A film shows a police radar speed meter in operation. This is doppler radar, measuring only velocity. Other film clips show the use of radar at sea for guiding ships into harbors, air radar for a flight across Lake Erie, and storm forecasting radar. Dr. Gebhard describes ground control approach (GCA) radar including a film of one hour of airplane flights compressed to a few minutes.