Twenty-four-hour dials are one of those experiences that watch enthusiasts have to try at least once. They’re like manual gearboxes, varifocal glasses or Marmite: you’ll either love them or hate them… as I learned when I wore one during an 11-hour flight with a nine-time-zone shift and arrived thinking that midnight was 6am. What’s undeniable, though, is their appeal to professionals, especially pilots: when you work on a 24-hour clock, nothing beats a 24-hour read-out. And amongst the genre’s granddaddies is Glycine’s genuine classic, the Airman.