One of my pet peeves is to see an engineer identified as a scientist, or an engineering achievement described as a scientific one. It happens all the time in the news media.
In October 2010, when 33 Chilean miners who had been trapped a half-mile underground for two months were brought safely to the surface, a headline in the Wall Street Journal described the "rescue formula" as "75 percent science, 25 percent miracle." In fact, as a participant in the feat was quoted in the story itself, the rescue was "75 percent engineering and 25 percent a miracle." It was engineers who had designed the advanced drill bit that enabled an access shaft to be driven in record time; it was engineers who designed the rescue capsule that was used to haul the miners out one-by-one; and it was engineers who had designed the ancillary equipment that was necessary to carry out the rescue.
The most generous way to excuse the headline writer for substituting "science" for "engineering" is to assume that he thought that the terms were synonymous. Headlines obviously have to fit a limited space and so shorter words are often favored over longer ones. But there is also another, less sanguine explanation for the substitution: newspaper people seem to associate scientists and science with positive accomplishments and engineers and engineering with negative ones. Thus, when the space race was young, it was common to read in the newspaper a successful rocket launch described as a scientific achievement and an unsuccessful one as an engineering failure.
Aerospace engineer and scientist Theodore von Karman, who directed the Guggenheim Aeronautical Laboratory at Caltech and was involved in founding NASA's Jet Propulsion Laboratory, is credited with formulating a simple distinction between engineers and scientists. In one of its many variant forms, his dictum says that scientists seek to understand what is, while engineers seek to create what never was.
This is a compelling dichotomy, and one that an engineer/scientist with the background and experience of von Karman was in a perfect position to formulate. What distinguishes the two pursuits may be said to be: engineering is the design of new devices and systems that serve a useful purpose that is not met by existing technology. The purest of scientists do not do this; they seek knowledge for its own sake, with no particular application or design in mind.