The Boeing 707 aircraft began flight in 1954, and by 1958 flew commercially in the airline service industry, which then helped Boeing to design its now famous 727 aircraft. This meant that in succeeding years more and more industries would require large amounts of computing power \cite[130]{sanders}. During that time the industry turned from using computers explicitly for design, to using them for numerical calculations and in manufacturing. Then in 1956, the Boeing Aerospace department acquired its first Numerical Computing (NC) machines, which where then used to produce fairly complex aluminum parts. By 1960, for the aerospace industry, these NC machines were ``a part of life'' \cite[131]{sanders}.


At this time, the industrialized world was acquiring large super-computers, even though there was not a way to generate \emph{renderings}. Then an engineer named of Norman Sanders who was at Boeing in 1959 describes how renderings were created: ``All design drawings were made by hand; the definition of every motorcar, aircraft, ship, and mousetrap consisted of lines drawn on paper'' \cite[129]{sanders}. This meant that with every drawing created by hand, even minor changes incurred labor-intensive re-drawing; some changes required that a print be completely re-drawn from scratch. At this time computers were used only as an intermediary doing calculations for an engineer which were then drafted by hand.


Input was entered into computers via punch cards, and then at night would generate output via a printer. This data could then be used by an engineer to create a draft, a procedure that had obvious inefficiencies: ``[t]here were cases of engineers spending three months drawing curves resulting from a single night's computer run'' \cite[130]{sanders}. This cumbersome method compelled Sanders to question whether or not computers could perform the task of drawing continuous lines and curves. But soon, with the help of Art Dietrich, Boeing sold their first software used to generate computer plots with printers. These plots, however, were far from accurate, and the Boeing drafting department refused to use them for design projects. To make matters worse, at this time Boeing would not invest any money in this type of research and development, because it wasn't efficient enough for their own use. In addition, no independent companies would engage in this venture because no market existed for it \cite[132]{sanders}. However, the world of \emph{computer-aided manufacturing} (CAM) came to the rescue. Computers had already been used to operate milling machines that accurately cut metal in three dimensions. After a stroke of insight, in 1961, a Boeing design team replaced the cutter head of these machines with a small diamond scribe, which allowed these machines to plot in two dimensions on aluminum sheets. And ``[p]resto! The computer had drawn the world's first accurate lines by machine'' \cite[132]{sanders}. However, as in any major engineering firm, the accuracy of this system required proof. So, in order to prove the competency of these drawings for the design of the Boeing 727, the project manager required that Norman's team generate 19 renderings of the Boeing 707's wing using this technology:


\begin{quotation}
We trucked the inscribed sheets of aluminum from the factory to the engineering building and for a month or so engineers on their hands and knees examined the lines with microscopes ... The chief engineer stood on his feet and said simply that the design lines that we had developed had been under the microscope for several weeks and were the most accurate lines ever drawn---by anybody, anywhere, at any time ... That is the closest I believe anyone every came to the birth of \emph{Computer-aided Design} \cite[132]{sanders}.
\end{quotation}
The success of this technology bound the Boeing 727 project to the computer not only for the manufacturing process, but for the design process as well: ``We computed the definition of the outer surface of the 727 and stored it inside the computer, making all recourse to the definition via a computer run as opposed to an engineer looking at drawings using a magnifying glass'' \cite[130]{sanders}. To confirm the value of these developments, the Boeing 727 was completed on time and on budget, which ``would not have happened had we not used CAD'' \cite[133]{sanders}.


Computer-Aided Design