You guys do it, too! As does all of South America. Japan, too. Seems like another hangover from colonialism in the rest of the world!:D

And where is the logic in the existence of the two measuring systems? I mean: kilometers - miles, kilograms - pounds, liters - gallons :06: :)

Not to mention the two opposite, righ and left-hand, traffic conventions :03:

Metrication is generally not a safety issue, except in engineering calculations, where there is usually lots of time to check results and find errors. Driving is a different story, but I don't believe there is any border where you can transition directly from a right-hand to a left-hand country. And even so, the side of the road everyone is driving on is usually pretty self-evident.

But consider approaching an unfamiliar harbor at night, visibility 1 mile, at the helm of a 40-foot sailboat. All you can see is a single green light ahead. Does it mark the right or the left side of the safe channel? And that red light that you can dimly see farther ahead - is it the opposite channel marker, or the port-side light of a supertanker moving down-channel? The answers to these questions are only of interest if you happen to be on that sailboat, and then they become VERY important to you personally!

Back to the original topic...
 

Well, if only it was all that simple and/or "standardized." But, it isn't and that's why trained, experienced and competent Navigators are always in demand, professional civilian mariners are Licensed, and why ocean-going vessels (including warships) are required to take aboard a local Pilot in almost any major seaport or waterway.

But first, it ought to be recognized that the IALA isn't really even relevant to the actual subject. :hmmm: The IALA wasn't organized until 1979 and the first conference was held in 1980 to rationalize (NOT "standardize"!) the 30+ different buoyage systems that existed at the time. That was a long, long time after the period of history covered by the Silent Hunter game series. Essentially every independent maritime nation had its own system of buoyage and Rules of the Road/Inland Pilot Rules, although many were copies of someone else's (or were originally implemented by the "Mother Country"); even the International Regulations for Prevention of Collisions at Sea (COLREGS) were a "work in progress" and weren't issued until 1960...and are still evolving.

Nonetheless, seeing as the topic had quite a bit of interest, I did a quick review of my pre-WW I and II copies of "Knight's Modern Seamanship", Dutton's 1926 "Navigation and Nautical Astronomy", and the 1951 "Admiralty Manual of Seamanship." They all seem to indicate that the buoyage systems in the game(s) are reasonably accurate representations of the separate schemes in effect prior to and during the war, although to avoid over-complication, they aren't totally correct in every detail. I'd say the Devs produced at least an "80% solution", good enough for game purposes.

WRT a couple of other points that were brought up...

The system in the Philippines was a U.S. system because the Philippines was an American "possession" since 1898; that system continued in use after they were granted independence in 1946 and was then naturally extended to the IALA B system. Although I couldn't find any particular references to the pre-WW II Japanese and S. Korean buoyage systems in any of my class materials (taught Navigation and Seamanship for quite a few years), I do recall seeing documentation a long time ago that alluded to the establishment of the U.S. system in those countries during the post-WW II occupation; aids to navigation of all kinds in Japanese held territories were almost completely destroyed during the war. As such, the IALA B system would be logically implemented there as well.