1. Au­topi­lot:

Passage Maker - - Electronics Products -

WWe were just a few hours out oof Lon­don, in the no­to­ri­ous Dover Straits on my fi­fi­first trip to sea aat the age of 16, when we col­lided with an­other ship in thick fog. It was only a glanc­ing blow so we were able to carry on with our voy­age, but it was a les­son about the dan­gers of fog. At sea, thinthings can hap­pen un­ex­pect­edly, and you re­al­ize just how your woworld changes when vis­i­bil­ity drops to zero.

That was be­fore the days of elec­tron­ics. We had no radar, no GPS, and no AIS, so it was a bit like nav­i­gat­ing with a stick and we had to rely on lis­ten­ing and lo­cat­ing fog sig­nals. Mod­ern elec­tron­ics have made a huge dif­fer­ence to nav­i­gat­ing in these con­di­tions. They give you con­fi­dence to keep go­ing when you can’t see ahead, and you tend to rely on them to­tally, which is where the dan­ger lies. GPS po­si­tion­ing on the chart plot­ter can give you a lot of con­fi­dence that you know where you are, but radar and AIS have their lim­i­ta­tions when it comes to col­li­sion avoid­ance in fog, and can­not be trusted im­plic­itly to de­tect ev­ery­thing that is around you.

TRUST YOUR SENSES

With two dis­plays in the pi­lot­house—one show­ing the radar and one the elec­tronic chart—you are likely to be fo­cussing on these screens rather than look­ing out of the win­dows. In the­ory, these two dis­plays show you ev­ery­thing you need to know, so why bother with keep­ing a vis­ual look­out? The prob­lem is that you can­not be sure that the radar will show ev­ery­thing that is mov­ing on the wa­ter, par­tic­u­larly if there is a sea run­ning. That is when the radar will pick up the re­turns from the waves as well as those from small boats and the small-boat re­turns can get lost in the sea clut­ter.

So the vis­ual look­out is vi­tal in fog, not only to re­as­sure your­self that you will see other boats that may be close but also it is a le­gal re­quire­ment un­der the Col­regs. Rule 5 states, “Ev­ery ves­sel shall at all times main­tain a proper look­out by sight and hear­ing as well as all avail­able means.” Hear­ing im­plies that you should be lis­ten­ing for fog sig­nals as well. I can’t re­mem­ber the last time I heard any ship mak­ing fog sig­nals and this re­quire­ment seems to be stu­diously ig­nored these days in fog, be­cause ships and boats rely on their radar alone.

In fog, you need all hands on deck, and the look­out should be out­side on the fly­bridge or deck. There, the look­out will not be dis­tracted by the elec­tronic dis­plays and will have a much clearer view. It can be a real strug­gle to keep the con­cen­tra­tion nec­es­sary for a look­out, so you need to change the watch at short in­ter­vals. It is best to have one per­son on vis­ual look­out and one on the radar so that full con­cen­tra­tion can be given to both.

OTHER CON­SID­ER­A­TIONS

Op­er­at­ing the boat on au­topi­lot in the fog has ad­van­tages. First, it re­moves the need to have some­one steer­ing

the boat so they can con­cen­trate on the look­out. Sec­ond, it will sta­bi­lize the radar pic­tures and make them much eas­ier to in­ter­pret. How­ever, make sure you know where the au­topi­lot dis­con­nect but­ton is so you can quickly take over man­ual con­trol. If you have MARPA on the radar to show the head­ing vec­tors of other ves­sels, then hav­ing the pic­ture sta­bi­lized will make these eas­ier to see. within the vis­i­bil­ity range, but ad­just for the vis­i­bil­ity range with on­com­ing ves­sels.

You are re­quired to pro­ceed at a safe speed hav­ing re­gard to the state of the vis­i­bil­ity.

Your speed should also be de­ter­mined by the char­ac­ter­is­tics, ef­fi­ciency, and lim­i­ta­tions of the radar equip­ment, and the pos­si­bil­ity that small ves­sels may not be de­tected at an ad­e­quate range.

Elec­tronic aids to nav­i­ga­tion do not ob­vi­ate the need for a look­out.

Heavy fog shrouds even large ships.

Radar and AIS match what the helms­man sees in front of him (be­low).

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