Unusual complication

I’m getting interested in Sicura watches; I was given a Sicura jump-hour watch as a boy by my parents for getting into grammar school and remembering that watch, long gone, took me on a nostalgia trip to find a replacement.

While looking I learned that Sicuras are not great quality watches, their prices are probably inflated by the unscrupulous practice of associating them with Breitling, but I’ve also found that many of the earlier ones are rather interesting, owing to the fact that the company founder was a clever engineer who designed watches with unusual complications.

Here’s one I saw and for the life of me I can’t work out how it’s used. I’m guessing the “Knt” on the outer bezel means it has a nautical connection. Other than that does anyone know how this works?

I would wager the top crown operates the internal bezel, which has a countdown function in 5 min intervals to 15 mins; so my guess would be this is a Yachting function (countdown to start).

Thanks, and what about the outer bezels? Any ideas?

Speed and distance amongst other things I'd imagine (?); similar to the Navitimer's slide rule. Can also be used for calculations / conversions as far as I know, but I'm far from an expert.

Could Knt stand for knots?

It does stand for knots. 1Knt = 1nautical mile per hour. 1knt. =1.15mph. 1 nautical mile = 1.15 statute mile.

That makes sense. Sicura also brought out a diver with an internal tachymeter and another with a GMT bezel. Perhaps they were anticipating underwater motor racing and thought people might want to know what time it was in the sea in different parts of the world?

Not a regular sliderule with matching logarithmic scales. This is specific speed/fuel/distance calculations. For example set the 1Hr triangle to 22 (for litres) then read off how many hours flying 55 litres in the tanks get you. Or climbing at 600fpm set the triangle to 60 (=600) and read off time to climb 4500ft. As with any sliderule the user has to work out where the integer numbers and decimal points lie. The Navitimer's innermost track is the same, the two outer ones being conventional log scales.

That's a cool watch man... regardless of whether its functions can be used or not. I used to have a Sicura too - but that was just a regular dive bezel one.