In today's world, we tend to take precision for granted. It's become the norm for even affordable mechanical watches to provide the level of accuracy and attention to detail that was once only achievable through extensive labor on separate movements and watches. By the mid-1700s, high precision in small timekeeping devices was attainable, as demonstrated by John Harrison. However, creating a precise marine chronometer by hand is vastly different from achieving consistent chronometer-level performance in mass-produced quantities of thousands or even hundreds of thousands of watches.
Longines was one of the most important pioneers in the manufacture of high precision timekeepers. In order to push precision to the limit, the company developed high frequency movements, but this wasn't the only method used by the company – its production of ships' deck watches, for example, relied on the classic formula of a large diameter balance coupled with a relatively low frequency (they were often mounted in gimbaled boxes, just as marine chronometers were).
One of the best-known chronometer-grade watches was the famous high-frequency Ultra-Chron, released in 1967 to celebrate the company's 100th anniversary (birthdays were a big deal for watch brands in those days). A period when wristwatch competition for accuracy was fierce, the Ultra-Chron watches used 36,000 vph movements.
The Longines UltraChron is a watch that ticks all the boxes of a proper vintage dress piece. Introduced in the late 1960s and produced for only six years, the UltraChron is an early attempt by the brand to mass-produce a mechanical watch that, according to their advertisements, was "the world's most accurate watch... guaranteed accurate to within one minute per month." This was achieved with the hi-beat Caliber 431 movement, which had a beat rate of 36,000 beats per hour.
A number of movements were used in the Ultra-Chron over the nine years of production. These included the Cal. 430 (centre seconds), Cal. 431 (centre seconds with date), Cal. 432 (hours and minutes only), Cal. 433 (date only) and some interesting manual wind movements which featured a hacking second hand which would stop when it reached the 12 mark (the Cal. 6952 with date and Cal. 6972 with day and date). The later Cal. 6651 and Cal 6652 models beat at a slower 28,800vph, but also had “Ultra-Chron” on the dial.
Other renowned brands, such as Girard-Perregaux and Seiko, also introduced their own high beat watches during this time period. Of course, Zenith made a significant contribution to the market with the release of the first high-frequency automatic chronograph in 1969. Meanwhile, Accutron timepieces were gaining popularity and the ultimate benchmark was to create a watch that could guarantee precision within one minute per month. The mechanical high beat watches and Accutron models both met this standard, with quartz watches only surpassing it when they became widely available. It's worth noting that Longines continues to offer high-accuracy quartz options in their VHP collection, with an impressive rating of ±5 seconds per year.
From 1973 on, when the COSC got into the game, the Ultra-Chron watches were chronometer-certified, and they came with a one-minute guarantee from the beginning. This was partly because dry molybdenum disulfide was used as a lubricant (which prevented oil from scattering off impulse surfaces, a problem early high beat watches faced).
The high frequency competition did not thrive in the late 60s and early 70s due to the explosion of quartz technology. But the Ultra-Chron line itself was still being produced well into the 1970s, so the types and models on the market were quite diverse, from a few hundred to a few thousand dollars, from elegant watches to timepieces. dive. After the quartz crisis, the Ultra-Chron watches were discontinued and consigned to the past.
The Ultra-Chron product line is attractive in its advanced technical solutions, impressive in its oscillation frequency, and mesmerizing fast-moving second hand. It not only demonstrates watchmaking skills, but also demonstrates the power of watchmaking. The strength of an entire company that dares to face new challenges, and Longines had such a time!