Complexity & Consistency, Comrade

 Two key elements of good design are simplicity and consistency. Good design, generally speaking, leads to a positive user experience. Design complexity and inconsistency may produce a poor user experience.

 You probably hear a lot about  “User Experience” in the context of digital marketing, and perhaps don’t think too much about it, or perhaps view the UX and design disciplines as being purely visual and superficial. But User Experience and its older, collared-shirt cousin Usability aren’t just about touchy feely brand attributes or broken links to cat videos. When design is inconsistent or overly complex, it can literally turn deadly.

 When you were a little kid, you probably struggled with the screw-cap on a bottle of apple juice and a parent or sibling told you, “righty-tighty, lefty-loosy,” thus introducing you to the concept of clockwise/counterclockwise design consistency. It’s a pattern so ubiquitous we take it for granted, like the sun rising in the east or water being wet. This “righty-tighty” pattern has always been around for everyone, right?

Not for Russian submariners during the Cold War.

 The tight/loose, clockwise/counterclockwise design pattern wasn’t consistent in the SovietNavy. On some submarines, to close a hatch, you turned the hatch wheel clockwise. On other submarines, to close the same hatch, you turned it counterclockwise. 

 On a cold night in January 1961, the Soviet submarine S-80 sank in the Barents Sea with a loss of all hands. Its disappearance was a mystery for seven years, until a Russian salvage vessel discovered the wreck. In 1969, Soviet investigators determined the cause of the tragedy. Rolling and pitching in rough winter seas while on the surface, the submarine began taking in water from a hatch. A Russian sailor, recently transferred from another ship, tried to close the hatch. He tried so hard he twisted the hatch wheel and stripped thin the threads of the bolt. But he was turning the wheel the wrong way. The water poured in, and the vessel flooded. (1)

 With regards to design complexity, Vanity Fair recently ran a fascinating article on the 2009 crash of Air France Flight 447 over the Atlantic titled “The Human Factor.” The author, William Langewiesche, investigates how the mysterious crash lead to larger questions about the design of Airbus cockpit controls and even of automatic pilot functionality in general. Human error leads to the design of complex automation systems. Complex systems can provide the wrong feedback data (the second “Stall” alert on Flight #447) or no feedback at all (pilot stick control with its fly-by-wire technology) confusing the user and leading to more catastrophic human error. Paradoxically, system designers frequently address incorrect feedback data – by making the system more complex! (2) 

 Avoid complexity and inconsistency. Keeping designs simple – and consistent – can be critical.

Footnote 1: See “A Time to Die: The Untold Story of the Kursk Tragedy” by Robert Moore, pp.80-81. Note that the Wikipedia article on the disaster  (https://en.wikipedia.org/wiki/Soviet_submarine_S-80) is at variance with Robert Moore’s account, citing the accident began with a snorkel valve failing to shut, leading to a machinist who “became confused with the complex array of valves” for the ventilation flapper. The Wikipedia version may reflect the original official Soviet report, which probably did not want to point to such elementary design flaws in its Whiskey-class guided missile submarine.

 Oddly enough, the hatch-closing inconsistency played a part in another Russian submarine disaster – the loss of the Oscar-class submarine Kursk in the summer of 2000. A team of Norwegian deep-sea divers was attempting to open the submarine escape hatch. The Russian Navy told them to turn the wheel one way. It wasn’t until they tried turning the wheel the other way that they were able to open the hatch.

 Footnote 2: Another good article about the design flaws that contributed to the Flight #447 is Fast Company’s May 2012 article “How Lousy Cockpit Design Crashed An Airbus, Killing 228 People” at https://www.fastcodesign.com/1669720/how-lousy-cockpit-design-crashed-an-airbus-killing-228-people