A couple of small but quite important things came along in the 1970s which we now take completely for granted. In the RAF we were issued with the standard issue Aircrew Watch. They were, of course, driven by clockwork and although they were considered to be valuable and attractive items, they were not really very accurate. They were all calibrated at the Greenwich Observatory and were probably as good as you could get for the time.
From a navigators point of view, having an accurate time piece was essential for measuring longitude.
Then along came the Seiko Quartz watch and they offered a degree of accuracy that had hitherto been only a dream. I bought my first Seiko 4004 in Masirah for £17 in 1975 and it is still going strong 42 years later. I simply have to change the battery once a year. Needless to say, the standard issue Aircrew Watch was handed back to stores very shortly afterwards.
The other great invention was the Personal Calculator. I was talked into buying my first one in Hong Kong shortly after I bought the watch. Compared to the modern version, it was huge but I was quite fascinated by it. I can remember sitting in a HK pub while we all tried to beat it by giving it quite complicated (we thought) sums to do. We didn't succeed. We were in Singapore a couple of days later and I found myself multiplying 50 x 2 on the new toy.
I suddenly wakened up to the fact that the thing was taking over my brain so I put it away for the rest of the trip. I flogged it to one of the navigators (at a modest profit) when I got back to Brize. (They found them invaluable for working out 3-star fixes etc).
Since then, I have continued to use mental gymnastics and will only ever use one to check my answer to some particularly complicated calculation.
I wonder how many of the younger generation could manage without one?