Historical Trivia:

The Dalton E-6B Flight Computer

The Dalton "E-6B" flight computer is made in many different versions by several manufacturers. This is one of the ASA models.

The Dalton flight "computer" is the sole remaining example still in production of the classic navigation slide-rule. Before the electronic-age, slide rules of various types were the back-bone of aircraft engineering and navigation. Aircraft manufacturers, as an example, had huge buildings with tens of thousands of technicians using slide-rules to compute sums related to aircraft structures. These technicians were called "computers", and the term was transferred to the electronic versions with the advent of the microprocesser.

The origin of this particular ingenious device appears to be centered on a US military scientist. Philip Dalton, a Cornell University graduate and US Naval Reserve pilot, developed a series of slide-rule flight computers in the 1930s, including the ever-popular E-6B somewhere around 1932 (originally called the Dalton Dead Reckoning Computer). However, aviation historian Kevin Darling notes that British navigation tools all carried the prefix "6B" to their part numbers, thereby causing some confusion as to the origins of the Dalton "E-6B". Regardless of the part number confusion, the Dalton Dead Reckoning Computer, or "E-6B", has survived to this day in slightly modified form through the hands of a large number of civilian manufacturers such as Jeppesen and ASA. ASA even makes a 6 foot tall classroom demonstration model available,