B-17G Cockpit Auxiliary Window F-105 Thunderchief The horizon sphere rotates freely

The horizon sphere rotates freely

Here is an interesting video describing how the K-13 functioned

The crewman or co-pilot operated a handgrip to adjust the aim of the externally mounted searchlight

1960s and 1970s

B-17G Cockpit Auxiliary Window F-105 Thunderchief The horizon sphere rotates freelyThis is a front left auxiliary cockpit window installed in some G model B 17's, although they could be retrofitted to other models. They could be opened inward to allow a pilot to de ice his main windscreen or, in the worst case, to see forward if the main screen was iced over. The internally facing, botton mounted handle unlocks when flipped up, and then the opened window would be affixed to the internal cockpit ceiling with the snap fit strap.