Clock changes are part of seaman’s life. The first time I heard about the ship’s time being retarded was, well, a bit confusing.

How could time be retarded when it only ticks and doesn’t think?

Then I learned that it will be moved backwards to comply with the Daylight Saving Time. Perhaps I wasn’t listening well in school, too.

As a day worker, it didn’t bother me much since I only need to adjust my clock one hour back. Plus it meant more sleeping time or movie time.

But when I joined the ranks of watchkeepers, clock adjustments suddenly became tricky, confusing and a source of quarrel sometimes!

Ship time will move backwards by 1 hour tonight

Ship time will move backwards by 1 hour tonight

Why adjust the time?

Everything a ship does is logged. And since the core of every ship is business and regulation, time keeping is a very important element.

It wouldn’t be a problem if the ship only does business with itself. But since our cargoes are loaded and discharged in different places, we must conform to the time of that place.

Normally, the Navigation Officer, with Master’s Advice, is in charge of watching out for these time changes.

Here are a few reasons why we need to adjust the ship’s time.

1. Avoid confusion

Setting the ship’s clock to local time avoids confusion between ship’s crew and shore personnel.

I work in a tanker ship and when the loading arm is connected, some jettymen ask for the time of connection.

Shore crew know more about the time of tide, the time agent or other visitors come, cargo completion and many others. Having the same time with them helps a lot to avoid miscommunication.

Another thing I experience was in the shipyard. We have to start working when the yard workers come. Same is true during lunch, coffee breaks and when the day ends.

2. Long voyages

When traveling eastward or westward, you may find your ship adjusting the ship’s time more often. A voyage from India to Mexico will give you 10 hours of incremental retards on your clock.

If done poorly, you may have your 9am darker than usual in some days. Time adjustments must be done accordingly like every 15 degrees of longitude.

4. Daylight Saving Time

In some places, the time is adjusted to conform to what is called Daylight Saving Time or DST.

DST is an internationally recognized practice wherein the clock is turned ahead during summer and backward during winter.

Not all countries practice this and those who do are mostly from the northern hemisphere where the days are longer during summer and shorter in winter.

Europe, North America, Russia and Australia are just a few places using DST.

Whether your ship anchors or sails in these areas in time for DST schedule, you may have to adjust your clock accordingly.

4. Documentation

As what I mentioned before, ships make money by doing business. And when we talk about business, remuneration is based on time.

Thus, ships record everything related to shipping business from start to completion of a certain voyage.

Besides, the vessel’s time log must also correspond with that of the shore crew- agents, surveyors, loading master, etc.

As visitors of their country, adjusting the ship’s time to local time also implies that we are highly cooperative.

Confused when the ship's clock is retarded.

Confused when the ship’s clock is retarded.

Only One Hour? How is this a problem?

Well, one hour wouldn’t be a problem. Its just one hour and why would someone cry when they lose one hour of their rest?

Assuming that only one watch, 12 to 4, will take the clock change. When the time is retarded, let’s say at 2:am old time, the new time will be 1:00am.

This means an additional one full hour of work to the 12 to 4 watchmen. The opposite happens when the clock is advanced.

If you have longer voyages and the same watchkeepers take the retard, this could be draining on their part and unfair too.

Thus, this one hour adjustment is the root of a few qualms.

Solution leading to confusion

The answer?

Time change is divided by the three watchkeepers, each sharing 20 minutes of the advance or retard.

Many approve this one as a fair solution, a just and equal method of conquering the 60-minute burden.

But on practice, its a bit confusing.

Some seafarers are discombobulated on what time they’re going to wake up and another in going on watch.

Since they are getting 20 minutes each, they should be 20 minutes earlier or later for work. It happens on a perfect world but on reality, its chaos.

This post will dispel all those puzzles so you can be on time on your watch.

Plus/ Minus One Hour? Here are some tricks

For day workers, no need to do anything other than set your personal clock- wrist watch, phone, wall clock to one full hour.

This guide is for watchkeepers and those who want to be on their ranks.

Crossing Multiple Time Zones

By far, this is the easiest way to deal with time changes.

Say your voyage is expected to advance the ship’s time three times before reaching the destination. The best method would be to give 1 hour of rotational advance to each watch keeper.

If you plan on adding an hour on Monday, Wednesday and Saturday during your 7 day voyage, the watchmen could have a piece of those time changes.

Monday will be given to 12 to 4 watch. Wednesday to 4 – 8 duty. And Saturday to the 8 to 12 watch.

No crying. No quarreling. No envy!

Great Sacrifice

Another trick is to get all the retards or advances by yourself.

If your voyage plies on few, same ports only, its also good to take the time retard by the single watch keeper.

When the time is advanced, that same watch keeper should also take it to compensate for his sacrifice.

But this needs total agreement with the others.

Dividing 1 Hour by Three

Another method in dealing with time change is to divide one hour (advance or retard) to three for the three groups of watch keepers.

This would give them 20 minutes each fair and square.

But as we discussed before, this is confusing in real life. Thus, we are here to solve it.

Advance by One Hour

Let’s talk about clock advance first.

First and foremost, chose your base time where you can apply the 20 minute increment. Is it gonna be the old time or the new time?

In this case let’s use the old time as the reference as this is easy to follow.

12 to 4 Watch

Since the time will be advanced, you must change the 8 to 12 watch 20 minutes earlier.

This means that you must be on the bridge on or before 23:40H using the OLD TIME.

When you enter on your watch at 23:40H, it will be advanced by 20 minutes so there you have it. Midnight!

4 to 8 Watch

Some watchmen needs 30 minutes before they can be ready for watch. Others need 20 while a few needs 15 or 10 minutes.

Don’t do the latter as your breath will surely stink during watch changeover.

No matter how many minutes you need for preparation, you must be on the Bridge on or before 03:20H OLD TIME!

Take note how I specified our reference time so as not to get confused.

When you come at 03:20H OLD TIME, it will be 03:40H using the 12 to 4 watch (20 minutes applied). Hence, if its your turn to have the 20 minute share, it will now be 04:00H (03:40H plus 20 minutes).

8 to 12 Watch

Now this is very easy for two reasons.

First is, 8 to 12 watch needs breakfast so they usually set their alarms earlier.

Second, before they sleep at the end of their previous watch, they only need to change their personal clocks one hour advance.

Thus, they already conformed to the new time because when they wake up, the time is already advanced by one hour!



One Hour Back or Retard

This is just like the former but opposite. Each watches will have 20 minutes retard instead of advance.

Since the time is moved back, you must add 20 minutes on the OLD TIME which is your REFERENCE TIME.

12 to 4 Watch

You have to be on the Bridge on or before 00:20H OLD TIME. By applying your 20 minute share, your new time will be 00:00H.

4 to 8 Watch

Your duty will start on 04:40H OLD TIME, UNADJUSTED!

Applying 12 to 4’s share will give you 04:20H. implementing your 20 minute portion sets your time at 04:00H.

8 to 12 Watch

Again, same logic as with clock advances.

Only this time, you can easily adjust your time to the new time and set everything like your usual routine.

Hope this helps alleviate the confusion. If you have more questions, hit me with an email. I’m currently in the middle of the Atlantic right now and my next post would be about my message in a bottle.

Or maybe something else.

Stay tuned and

May the winds be in your favor.

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