Skip to main content

ONR Historical Timeline 1930-1940

  • Uranium 235 Production

    Image
    Uranium 235 Production

    Naval scientists developed methods for producing uranium hexafluoride and separating isotopes using liquid thermal diffusion. These methods were vital to uranium 235 production and were used to create the atomic bomb.

  • Plan-Position Indicator

    Image
    Plan-Position Indicator

    PPI was developed between 1939 and 1940 by the Naval Research Laboratory in response to a need for a display that would show the range and bearing of all targets "visible" to the radar. NRL created a polar-coordinate map-like display of targets—the well-known radar scope with the round face and the sweeping hand. PPI is used worldwide with detection, navigation, air traffic control and object identification radar systems.