Cases: Error & Accident Investigations
A catalogue of the book's accident examples illustrating "Human Error? No, Bad Design" (the thesis) and Root Cause Analysis and the Five Whys.
Three Mile Island (1979, ch.1): Nuclear accident initially blamed on "human error." Norman's committee found the control rooms so poorly designed that error was inevitable — design was at fault. This case converted Norman to design.
F-22 crash (2010, ch.5): Air Force blamed "pilot error" (failure to recover from a dive). The DoD Inspector General (2013) did proper root-cause analysis: the pilot was probably unconscious from oxygen deprivation. Parody: "It was pilot error — he failed to act." / "Because he was unconscious." / "So you agree, he failed to act." Shows root-cause analysis stopping as soon as a human is found.
Gimli Glider (Boeing 767): Two mistakes — knowledge-based (fuel computed in pounds instead of kilograms) and memory-lapse (mechanic's troubleshooting interrupted). Plane ran out of fuel mid-flight. See Error Taxonomy — Slips and Mistakes.
Airbus descent accident: Mode error — pilots thought they were setting descent angle (−3.3°) but were in vertical-speed mode (−3,300 ft/min). Fatal. Fix: display angle (2 digits) vs vertical speed (4 digits) distinctly.
Royal Majesty grounding (1997): Automation paradox + mode error. A disconnected GPS antenna cable silently switched navigation to "dead reckoning" (tiny "dr" indicator unnoticed). Years of flawless automation bred over-trust; the ship drifted south and grounded on Cape Cod. Human "out of the loop."
Electric-utility electrocutions: Committees blamed the (skilled) workers and stopped. Fixable by simple procedure changes, but the "we are supermen, we don't err" culture blocked it. Years later: "No changes… still injuring people."
Cross-cutting lesson: most accidents are multi-cause (Swiss cheese); blaming one person feels good but fixes nothing. See Designing for Error.
Confidence
1.0 — explicit cases.
Sources: ["DOET ch.5 (F-22 p.164-167; Gimli Glider p.171; Royal Majesty p.214; Three Mile Island ch.1)"]