*"whiz-wheel" - plastic, round slideruley thingy often found in the breast pocket of a pilot or less often in a "leather" pouch in a "brain bag" - the device was equipped with "analog scales" upon which could be done manual calculations of remarkable variation and accuracy. The "other side" of the device modelled "trignometric functions" for actual (real-time) wind "calculations" so that the pilot might track between points with some accuracy. One could find true airspeed, density altitude, do pressure-pattern flying and even find distance and track between two points of latitude and longituded when flying the Atlantic and Pacific, verifying what the Doppler and/or the Loran were telling the pilot. The device, manufactured by the historical map-maker Jeppesen and known as a "CR2" and for those who's eyes were challenged, the "CR3" were humourously known as "computers" at the time.
Still have CR-3's in my two flight bags...most recently used for ETP calculations. Batteries not required.
