Longines Twenty-Four Hours Reference L2.751.4.53 - The Watch used by Swissair Navigators .In the 1950’s Longines supplied watches to the Swiss national airline, Swissair. These timepieces, which had been developed specifically from the brand’s aviators’ watches, had a very distinctive 24-hour dial. This technical characteristic met the needs of navigators who, at the time, had to determine the position of the aircraft and set up a flight plan. Longines has now re-issued this watch for both historical and functional reasons, as well as for the aesthetic attraction it still holds. The new version has been given the name Longines Twenty-Four Hours.

In 2009, Harry Hofmann, a retired navigator from the old Swissair, visited the Longines Museum. He took advantage of this visit to present the company with a Longines watch that he used to wear when he was working for Swissair. This watch, with its 24-hour dial, is part of a series of timepieces produced by Longines in the 1950’s especially for Swissair navigators.

The case, in stainless steel, measures 47.5mm. It has an AR-coated sapphire crystal and an engraved back cover on top of a sapphire display back. It is water resistant to 30 meters.

Movement is the Swiss automatic Longines L704.2 (base Valgranges A07-171) with 24 jewels, 28,800 vph and a power reserve of 2 days. Functions are hours, minutes, seconds, date, 24-hour circle on dial. This caliber makes one full circle of the dial in 24 hours.

The dial is matte black with 24 white Arabic numerals with Super-LumiNova coating and a Railway track minute circle with date aperture at 3 o’clock. Hands are skeleton pear steel hour-hand with Super-LumiNova coating, skeleton leaf minute-hand with Super-LumiNova coating and stick with drop counterweight seconds hand.

The strap is black alligator with a Longines buckle.