Radar Use

[Mike Turner]

When we bought our Lazyjack schooner last year, it was outfitted with a working, old-model Raytheon radar set. We tested it during the survey; otherwise I haven't used it much due to its drain on the battery.

We've been having quite a spirited discussion lately at my marina on when radar use is required. Some have been advocating the position that, once a boat is outfitted with radar, it must be used.

Others, myself included, interpret the Inland Rules for Navigation to read that radar must be used in "appropriate circumstances". The actual language is,

RULE 7: RISK OF COLLISION

(a) Every vessel shall use all available means appropriate to the prevailing circumstances and conditions to determine if risk of collision exists. If there is any doubt such risk shall be deemed to exist.

There is general agreement that, should one be so unfortunate as to be in a collision, the Coast Guard will expect that the radar have been employed to attempt to avoid the collision - the general feeling being that, if there was a collision, it must have been preceeded by a risk of collision, and that would constitue "prevailing circumstances" to call for use of "all available means" to determine if that risk exists. Of course, this general agreement could be construed to mean that the radar should be employed even in sunny, calm conditions if a risk of collision exists.

I've been leaving the radar control head down below on our daysails, because the radar seems to be a real energy hog. So far our sails have not been in fog or any low-visibility conditions, or at night; but we're planning some longer-distance cruising in a couple of months and those conditions could come up. I feel I'd definitely use the radar at night, in fog or in low-visibility; but I don't want to run it on clear days if I don't have to.

I'm curious - if your boat is outfitted with radar, under what circumstances do you use it? All the time? At night? In fog? Other?

My chief concern is battery depletion. I'll admit that I haven't run the unit enough to fully judge battery drain, particularly in all modes; but from the times I have run it, it seems to pull a lot of power. My battery banks are all new so battery condition isn't a factor.

Mike Turner
Lazyjack 32 schooner "Mary'Lis"
Mobile Bay, Alabama

 

[Rich Stidger]

I have an Autohelm (Raymarine) RL70 radar with a 24" 4Kw antenna. The draw is about 5A. Your radar may draw more power if it is a CRT-type of display.

My practice is to use the radar at all times underway.

The primary reason for using the radar during times of perfect visibility is so that I will become accustomed to seeing radar pictures of what I see around me. Reading a radar is not intuitive, and takes practice. Understanding exactly how the image on the radar translates to direct visual is important when the visibility does drop to zero and you must rely on the radar image to interpret land shapes, buoys, and other vessels around you.

It is also my understanding that if you have a working radar on board you should be using it per the nav regulations. I could be wrong on this interpretation, but nevertheless this is what I adhere to.

 

[windward54]

I'm about 50/50 with Rich on this one. Although I don't think radar is manditory at all times, I run mine a lot when I'm around the shipping lanes here in Southern California. I have found that unless you practice when visibility is good, you will have no idea what you are looking at when you really need radar.

 

[Rick D]

Ditto Those Two Guys...

....use it full time when motoring, but you can put it on intermittent scan when sailing. If things are perfectly clear, no problem as long as you don't hit anything. However, I run mine most of the time to get a familiarity with the targets. It pays off in pea soup or entering a messy harbor at night. Like I said, I check periodically under sail and in clear conditions and leave it in standby otherwise. Hope this helps.

 

[capejt]

another vote for Rich

I too agree with Rich. If you can afford the power drain, it couldn't hurt to have it running, especially in high traffic areas and shipping lanes.

 

[Chuck Creel]

I have an Autohelm (Raymarine) RL70 radar with a 24" 4Kw antenna. The draw is about 5A. Your radar may draw more power if it is a CRT-type of display.

My practice is to use the radar at all times underway.

The primary reason for using the radar during times of perfect visibility is so that I will become accustomed to seeing radar pictures of what I see around me. Reading a radar is not intuitive, and takes practice. Understanding exactly how the image on the radar translates to direct visual is important when the visibility does drop to zero and you must rely on the radar image to interpret land shapes, buoys, and other vessels around you.

It is also my understanding that if you have a working radar on board you should be using it per the nav regulations. I could be wrong on this interpretation, but nevertheless this is what I adhere to.

even the best radar is useless in knowing hwere you are as opposed to just avoidiing an object because it shows up on radar. On my job i can just look at the whole radar screen and point to objects and know what it is. there fore telling me excatly where i am in relation to it.

EXAMPLE:

The safety fairway entering the mobile ship channel is at beacon 34-36. The dayboards / bouy's here are arannged differntly from the others in that they are a triangle rather than across from each other.

Also ICW crossing at pascagoula ship channel, dayboards are wider at the crossing than any other place in the channel.

Just an example of kowing what your looking at.

I am no genius, but 15 years of looking at radar from mobile , al to new orleans,LA repeatedly has become familiar, kinda like seeing a photo.


Fair winds;
See ya at the sunk boat harbor Mike.

 

[higgs]

I read an article a number of years ago about a couple who was sailing in the fog and because of battery drain did not have their radar on. They got in a collision and the CG found them at least partly at fault for not having their radar in use.

 

[Mike Turner]

Thanks to all for the input!

 

[Ray Bowles]

When we were cruising a few years ago we found the radar a very valuable tool at night. Fog wasn't much of a problem during the day but at night everything is a problem. In addition to all the standard threats you find at sea one bonus was in being able to see storms at night.
We set our range at 12 miles. Even though curvature cuts into this range it gives 2+ hours of warning. Summer rainstorms with their violent winds are a real problem at night so we always ran the radar. We had wind and solar power so draw was't a problem for us.
Ray