Navigation and Bombing System

The Navigation and Bombing System, or NBS, was a navigation system used in the Royal Air Force's V-bomber fleet. Primary among its parts was the Navigation and Bombing Computer (NBC), a complex mechanical computer that combined the functions of dead reckoning navigation calculation with a bombsight calculator to provide outputs that guided the aircraft and automatically dropped the bombs with accuracy on the order of a few hundred metres on missions over thousands of kilometres.

Inputs to the NBS system included late models of the H2S radar, the True Airspeed Unit, an astrocompass, the Green Satin radar, and a radio altimeter. These inputs were used to set the Ground Speed Unit, which carried out the navigation calculations, which in turn fed the NBS. The NBS, in turn, fed the Mark XIV bomb sight for visual sighting, as well the autopilot systems.


  • Bonnor, Norman (1997). "Chapter 10: From the 60s to the 80s, The Last Days of Airborne Analog Computing" (PDF). History of Air Navigation in the RAF. pp. 98–106. Archived from the original (PDF) on 2017-08-03.