So, being the nerd I am, I was recently working on an Imperial Time converter (mainly so I could post thinks like "Captain's Log, Stardate 1 024 898.M41". As I mentioned, nerd).
(also, if anyone is interested in playing with it, it can be found here on jsfiddle. The working page appears in the lower right quadrant).
Anyways, what I ran into is you really can't convert our time to Imperial with out a computer program, at least without doing some calculations. The main issue is that the Imperium doesn't track days (why would they? Most planets don't have a 24 hour day), or months.
Instead they break a year down into 1000 units, and count those. So July 1 = 50% of the way through the year = 500 on the Imperial Calendar. So 0 500 014.M3 is July 1, 2014. And I largely agree with the system. It makes sense to use earth years and millennia for synchronization, but not days and months.
That further got me thinking, ship days really shouldn't be 24 hours either. Look at real world submarines, they operate on an 18 hour day with 3x6 hour shifts.
Now assuming people on a ship don't want to have to break out their calculators every time they need to write a date down, I'm assuming the ship would operate on something a bit more predictable in terms of their calendar, trying to get as close to a 24 hour day as possible. This gives us two possibilities:
A 333 day year with ~26 hour days, and a leap year every three years. So each day increments the calendar 3 ticks.
A 500 day year with ~18 hour days. No leap years. So each day increments the calendar 2 ticks.
After doing a fair amount of math, I'm strongly in favor of the 500 day year. In a 333 day year months, weeks, and shifts are all a nightmare, and you have that leap year. Bonus points to the 18 hour day because that is what submarines do today.
So, going with a 500 day year, I'm torn on months and weeks, primarily because the various RT rulebooks occasionally refer to them, and it's easier on the GM if that doesn't change. If we leave 12 months in a year, each month is 41-42 days.
But if we're fine with changing months, we can have 10x50 day months in a year, with 10 days in a week.
Finally, shifts. As I mentioned, real world submarines have 18 hour days. Each day as 3x6 hour shifts. So you are on a 1/3 on 2/3 off work schedule. They do this because most submarine work is important, requires 100% attention, dangerous, and extremely monotonous. And any mistakes can threaten the entire ship. 6 hour shifts are the longest it is safe to have someone focus on monotonous tasks before they start missing things.
At first I wasn't for this on an Imperial ship. After all, horrible working conditions are a pretty core part of the fluff of 40k. On the other hand, this is a ship, and a big part of the poor working conditions on a ship is the boredom and isolation, not the hours. Even the rule book makes mention of this. And a Rogue Trader ship (and most military ships) is going to be more focused on efficiency and ship safety than, say, the IG. These ships are ancient holy relics. So maybe they would focus on taking care of them. Besides, we can still abuse the ratings mercilessly.
So this is what I think I'm settling on as at least one good candidate for a ship schedule:
500 day year, 50 day month, 10 day week, 18 hour day, 3x6 hour shifts per day.
Obviously there are other possible sensible configurations (I mentioned 333). But I think it's safe to assume that a 365 day year with 24 hour days just doesn't work very well on an Imperial starship, especially when combined with the standard Imperial Dating system.
So thoughts? Critiques?
Edited by riplikash, 06 February 2014 - 01:53 PM.