No. The Navigator does need to be able to talk to the pilot though, usually this was done by intercom, but to take the example of the B-17 (Just because you happen to have been inside of one, you lucky..... ), the Navigator and Bombardier were in the nose and manned the nose/chin or cheek guns when they didn't have more pressing duties, whilst the pilot, co-pilot and flight engineer were in the cockpit area.
In most RAF bombers from WW2 the navigator was in an entirely seperate room from the rest of the crew. This was because the RAF tended to bomb at night, and the navigator needed to put on a light to see the chart. Any lights in the cockpit would have both reduced the pilot's night vision and given the plane's position away to nightfighters.