Watches: how timepieces played a crucial role in the Second World War

Historians can argue all day long about what won World War Two, but the one thing they all agree on is that without the massive expansion of US air power, things could have turned out very differently. And the wristwatch played a vital role, employing a neat little function that has since become commonplace.

In bombing raids precise timing is crucial and the Allies relied on clockwork to coordinate attacks. Even the best quality watches were not that accurate by today’s standards, with precision of plus or minus 30 seconds a day. So pilots needed to synchronise timepieces before heading out, and this required a ‘hacking’ mechanism.

On a quartz watch, when you pull out the crown it breaks the circuit powering the mechanism and the ticking will stop. A mechanical watch requires an extra bit of kit to make this happen. When you pull the crown on old mechanical watches, or on some cheaper modern ones, you can adjust the hours and minutes, but the seconds hand just keeps going. The hacking, or stop-seconds, function introduced a little lever that pushes onto the balance wheel, pausing the seconds hand so you can set the time precisely.

This function, invented in the early 20th century, was top of the list when US military ordered the A-11 spec wristwatch for WW2 troops. Other stipulations included: easy grip crown, olive drab strap, ‘unbreakable’ acrylic crystal and stainless steel caseback with serial number, manufacturer and military regiment. Three US watch manufacturers – Elgin, Waltham, and Bulova – were engaged to make the watches, and thousands were distributed not just to American troops but across Allied forces. The popularity among pilots has seen collectors label the A-11 “the watch that won the war”.

While America boomed, its watch industry dwindled. Of the three companies that made the A-11 watches, only Bulova remains in business and is now Japanese-owned. There is a lot of nostalgia for WW2 watches, in no small part because WW1 watches were a bit rubbish – cobbled together on the fly, rather than purpose built. In World War Two, we got proper mil-spec watches for the first time. If they also played a part in keeping us safe from the Nazis, no wonder so many of us are keen to get in on the action.