What Engineers Know and How They Know It: Analytical Studies from Aeronautical History Book

A. Synopsis
1. This book is an intellectual history of technology. It studies engineering epistemology and argues that science and engineering are separate branches of knowledge. The main emphasis is on the design aspect of engineering process. The book includes 5 case studies which show how the needs of design cause the growth of a particular type of knowledge.
B. Related works
1. Edwin Layton, "Technology as Knowledge." Layton sees technology as a spectrum with ideas and techniques at the poles and design in the middle. Types of design include ordinay engineering (neither the design nor the central parts are new), invention (new design with familier component parts), innovation (new design, new parts).
2. Edwin Layton, "Mirror Image Twins."
3. Eugene Ferguson, Engineering and the Minds Eye. Good engineering requires intuition and non-verbal thinking as much as it does theoretical, abstract equations and computation (2 types of knowledge). When the non-verbal side of engineering is ignored (like the present day) disasters occur like th Chalenger, Hubble, Three Mile Island.
C. Engineering as Knowledge
1. The engineering process
a) Organize: bring into being
b) Design: the plans from which an artifact is built
c) Production: the process of transforming plans into artifacts
d) Operation: the use of the artifact
2. Types of design (which is the focus of this book)
a) Normal design: What the technological communities usually do. Like Layton's ordinary engineering.
b) Radical design: A new design or "innovation"
c) Hierarchal: This hierarchy consists of project definition, overall design, major component design, lesser-component design, specific problems.
(1) This book deals with the lower levels of the design hierarch because this area has often been ignored.
(2) Contextual factors influence design. This influence is greater at the higher levels of the hierarchy where the projects are defined.
D. Case studies which show how the needs of design cause the growth of a particular type of knowledge
1. Design and the growth of knowledge: The Davis wing and the problem of airfoil design, 1908-45
a) Here a specific knowledge arisis (how to build a better wing) from the demand of a particular specification (better efficiency and less drag)
b) The Davis wing was invented by the lone inventor David Davis in 1938. It was used successfully for the B-24 bomber. It became one of the most successful bombers of the war. After WWII the wing was never used again and had little impact on further aeronautical technology.
c) This case study examines how engineers work in the face of uncertainty (how to explain the Davis wing). Uncertainty is followed by the attempt to incerase knowledge. Thus, the growth of knowledge and the reduction of uncertainty in design are closely related.
2. Establihment of design requirements: Flying-quality specifications for American aircraft, 1918-43
a) In this chapter the initial problem is not well defined (a subjective pilots claim of "tail heavy logitudinally.")
b) This case study explores how engineers took these claims and turned them into a specific criteria for hardware.
c) Thus, the history of flying-quality specification is the history of an idea. This idea is that pilots needs can be incorporated into aircraft design.
3. A theoretical tool for design: Control-volume analysis, 1912-53
a) This case study explores how engineers think about their problems differently from scientists.
b) Engineering creats artificts, science creates understanding.
c) The example here is how both disciplines treat thermodynamics.
(1) Engineers use the idea of control-volume (imagined spatial volume with particular characteristics) ex. Boiler models.
(2) Physicists use neither these ideas or models.
4. Data for design: The air-propellor tests of Durand and Leslie, 1916-26.
a) Durand and Leslie were 2 mechanical engineers who studied aircraft propellers to learn which was the best specific design.
b) This case study examines their particular methodology. Knowlege about how to acquire knowledge is a form of knowledge (much like the internet)).
5. Design and production: The innovation of flush-riveting in American airplanes, 1930-50
a) In the 1930s all aircraft were held together with dome shaped rivets.
b) Ten years later all had flush rivets.
c) What knowledge was necessary for this to take place.