Why does the armed forces use 24 hour time an not 12hour time?

Question

notices dvd players run on 24 hours for recording

Answer 1

Primarily to distinguish between daylight and nighttime operations

It would be really embarrassing - and possibly deadly - to want to begin an operation at 4PM, and have it start at 4AM.

In addition, the 24-hour standard can easily be matched to the international clock out of Greenwich, England.

Finally, it just sounds cool to say something like zero-four-hundred hours, instead of just plain old 4AM.

As to DVD players and other electronics running on 24-hour time, remember, even if they are turned "off," they are technically "on," because electronics never sleep - it just rests waiting to get us hooked again ...

Answer 2

To avoid confusion between a.m. times and p.m. times.

Have you ever accidently set your alarm clock for 6:00p.m. instead of 6:00a.m.? You can't make that mistake if the times are 0600 and 1800.

Most of the world uses 24-hour time for tranportation schedules, such as train, airplane and ferry schedules.

As for the military, can you imagine what a FUBAR it would be if a unit was supposed to attack an objective at 11:00p.m., and they thought the message was 1100a.m.? Whoops... If the message read 2300, then there is no confusion about the time.

The military also uses specific date formats for the same reason. YYYYMMDD (20080820), or DD MMM YYYY (20 AUG 2008).

Answer 3

The origin of the 24 hour clock started with an individual who was waiting for a train.  The train was leaving at 5.  OK.   He got there early to get his train but it wasn't at 5 PM as he thought.  It was at 5 AM.  So he missed his train by a full 12 hours.

He then came up with the idea of using a 24 hour clock and added 12 to the times past noon.  So 1 PM became 1300, 2 PM became 1400, etc.

That is the way I remember the story anyway.

Answer 4

Because there is much less possibility of screwup when making arrangements, giving orders, or discussing chronological events. the difference between a.m. and p.m. can result in death. But the difference between 1000 and 2200 is unmistakeable.

Answer 5

If we attack the enemy at 3pm we do not want the air cover showing up at 3 am.

Answer 6

I would imagine it would be for clarification. We will attack at 4:00. Would that be 4:00 AM or PM.  

Answer 7

meet me at 1 oclock.........do i mean in the early morn or.....do ya get it now???

Answer 8

Makes coordinating things a lot easier. I mean you do not want a squad or whatever attacking a certain point at 2pm when you won't have be able to provide support until 2am.

Obviously they could just specify am or pm, however someone's eventually going to forget. So they use 24 hours to avoid problems.

Answer 9

to avoid confusion between am and pm over the radio 1300 is more clear then 1:00 pm

Answer 10

Simplistically:

There are 24 hours in a day.  It is LESS confusing to use 12:15  and 24:15 rather than 12:15 PM vs 12:15 AM.

Besides its pretty much been standardized with Police, Rescue, Hospitals, Fire and others.  I do Security and it drives the CLIENTS crazy until they figure out that on a 24 hour site, its MUCH easier.

I won't buy a digital watch that won't go military time.... Its first nature to me after growing up in a HARD Corps military family.

Don't ask about ZULU time, that still trips me up!

exerpt from attached link:

Civilian time uses the numbers 1 to 12 to identify each of the 24 hours in a day. In military time, the hours are numbered from 00 to 24. Regular and military time both use minutes and seconds in exactly the same way. (For example 1:05PM would be 1305 hours.) When converting from regular to military time and vice versa, the minutes and seconds do not change. Midnight is written as 2400 or 0000.

Answer 11

Because theres 24 hours in one day. Two twelve hour periods create questions about what time someone is to report to a specific location. So to eliminate mistakes, they made it a 24 hour system (like most of the world uses).