BREITLING’s conquest for precision further solidified in 1942, when it expanded its range of wrist worn instruments by creating its flagship model, the Chronomat, which featured an integrated circular slide rule, applicable towards multiplication and division calculations. It was the first watch to feature a such, which was made up of a mobile outer scale, operated by rotating the bezel- sliding it around another fixed scale on the dial rim.
The popularity of the invention really reached the heavens in 1952 and onwards, when BREITLING adapted it to airborne navigation requirements by reversing the direction of the outer scale, and adding reference points to convert kilometers (km) to nautical miles (naut), or knots, as well as to “statute” or standard miles (stat). In 1952 a watch was born that would become the cult object of pilots: Navitimer, short for navigation and timer. The slide rule could handle all rule of three calculations, and all required calculations relating to aerial navigation, preparation of flight plans and or daily life. Easy to use, it could also determine fuel consumption, rate of climb or descent, average speeds and conversion of distance. Pilots raved for they know had a “hand- held computer” on their wrist. BREITLING‘s most iconic timepiece was born.
BREITLING’s Navitimer’s reach surpassed the heavens 10 years later with the onset of space exploration. In May 1962, worn by Astronaut Scott Carpenter aboard Aurora 7, the Navitimer orbited the Earth. “The watch in space. The watch that timed the astronauts,” BREITLING called it.
BASIC FUNCTIONS MADE EASY WITH THE SLIDE RULE
Rotate the bezel until the figure 12 on the outer bezel is directly above the index number 10 (red) on the inner scale. The result, 84, will appear on the outer scale, directly above the 7 on the inner scale.
Division ( 120 by 4)
For any division calculations, using the circular slide rule, you must add or remove a zero at the end of the given numbers. In this case 120=12 and 4= 40. Rotate the bezel until the 12 (120) on the outer scale is directly above the 40 (4) on the inner scale. The result, 30, will be displayed directly above the index number 10 (red).
Place the supposed exchange rate, multiplied by 10 (1.40 U.S.D.= 14), on the outer mobile scale, directly above the index 10 (red). Amounts expressed in euros can now be read on the inner scale, while amounts in U.S. dollars can be read on the outer scale, i.e. 40 €= 56 U.S.D. and 70 U.S.D. = 50 €.
Tips (Check= $100, Tip= 15%)
Place the desired percentage tip amount (15%=15,) on the outer mobile scale over the inner index 10 (red). The inner scale displays the total of the check ($100= 10), zeros would have to be added or removed depending on the value of the check, while the outer mobile scale displays the amount of tip ($15=15), wherein a zero too may need to be added or removed depending on the percentage/ check amount.
Rule of Three: Rate of Descent
A pilot is flying 3,3000 meters, and notices that he is losing altitude at a rate of one meter per second (60 meters a minute). What is his remaining flight time?
Place the figure 33 (3,300= 33) on the outer scale directly above the figure 60 (60 meters) on the inner scale. The result will be displayed directly above the index 10 (red) on the inner scale on the outer scale, 55 minutes.
In 1942 BREITLING once again revolutionized the industry, by incorporating a circular slide rule in its flagship Chronomat. Ten years later in its Navitimer, the slide rule was changed to satisfy the necessary calculations of a flight plan and to feed into a niche who desired precision instruments: pilots. Able to calculate any multiplication and division equations, it received instant acclaim, becoming the brand’s iconic model. Pilots rejoiced at their new hand-held “computer.”In 1952 with the invention of the circular slide rule in its Navitimer, BREITLING accelerated its climb into the heavens, and has not often touched ground since then.