Lots of history and other info about Navitimer in this video, thanks for that! What I would like to see more about is the slide rule. It is the main feature of the watch, but often these review videos pass it by just mentioning that it can be used for various calculations. You, too, say that you're not using it actually. Well, here's a brief intro and a practical hint or two: The main point with the slide rule is that when you rotate the bezel, you are setting a ratio over the whole circle. For example, if you align 10 on ones scale with 20 on the other scale, you have set a ratio of 2, and it is constant everywwhere. 30 aligns with 60, 22 aligns with 44 and so on. You have to keep track of the magnitude of numbers though, as the numbers on the scale don't tell that: 22 on the scale can mean 2.2, 22, 220, 2200 or whatever with 22 in the beginning of the number. For one thing, you can use this as a handy currency converter. Say, if 1 USD is 3.8 Papua New Guinean Kin, you would align 10 with 38. Now you can immediately read all conversions! You can just read on the scales, for example, that 30 aligns with 11.5 (or thereabouts) which means that 3 USD = 11.5 Kin, or 30 USD = 115 Kin etc. It is not as exact as using a calculator, but it can be very handy as you don't have to type in any numbers. What about speeds? Let's say we have flown 180 miles and used 25 minutes for that. Let's use the outer scale for miles and inner scale for minutes. You align 18 (on outer) and 25 (inner) and what can you learn? You have set the ratio (speed), and you can read that at 60 minutes the number on the miles scale is 43, which means 430. So your average ground speed is 430 miles/hour. If your trip length is 800 miles, you see that it will take a bit over 110 minutes keeping this speed (80 is close to 11). And so on, you can see much of things just looking at the scales, you don't really need to think about multiplications and divisions in cases like this. And now we come to the accuracy. How good are the results depends on how accurate the slide rule scales are. I have never seen a reviewer check that, even though it would be a sensible and easy thing to do! Just rotate the bezel to a few simple ratios, like 2, 4, 5, 6, and check if the scales give you correct readings for these around the bezel. An expensive watch should have accurate scales, but I sometimes hear that even Breitlings can be a little off. I guess the slide rule is for most users just a decoration on the watch, but it should still be a useful instrument.
Thanks for the comment! This is great info. I have a website link saved that explains everything the slide rule can do. I am a retired US Submariner and in that line of work I had to use multiple tacaids that assisted with navigation, weapons employment, and target tracking. Some of them were similar to the Navitimer slide rule. Because of this, the Breitling slide rule holds a warm spot in my heart. Please consider subscribing and checking out my other videos. I have a rather large watch collection/ obsession and created the channel as an outlet to talk about the different brands and their history. It also spares my friends and family from all my boring watch talk. :)
