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Thread: Nav Rule Question on the Use of Radar on Sailboats Reply to Thread
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  Topic Review (Newest First)
07-21-2011 05:01 PM
Originally Posted by Boasun View Post
But if you are single handing the boat or a couple standing separate watches, they can't be running below decks every few minutes to view the radar screen.

Boasun, that's what autopilots are for --

Night watch -- one watch stander awake
Autopilots ON, boat's on course at six knots.
Quick scan of the horizon.
Duck below -- hit "transmit", let it settle, look at 8 miles (three scans), 4 miles (three scans), 2 miles (three scans), 1 mile (three scans). Hit "standby". Pop back up to the helm.
Quick scan of the horizon.
Elapsed time 90 seconds... distance traveled 300 yards).
Ten minutes later....repeat the above. (Distance traveled since last radar check ~ 1 nm).

Now, if you're in the fog or you can't see the reduce boat speed, but the process is the same.

The exercise keeps you young.
07-21-2011 12:03 PM
Originally Posted by Boasun View Post
But if you are single handing the boat or a couple standing separate watches, they can't be running below decks every few minutes to view the radar screen.
Then given how the law reads, it might be in their best interest not to have it installed at all.
07-21-2011 11:31 AM
Boasun I've noticed that a lot of boats have their radar repeater installed at the chart table and not near the helm. This means that in order to use said radar, you will need someone who is savvy on the use of radar and is willing to sit down below and watch the screen.
But if you are single handing the boat or a couple standing separate watches, they can't be running below decks every few minutes to view the radar screen.
07-10-2011 11:27 AM
Slayer I am an attorney and am pretty skilled at cross examining witnesses. At the negligence trial after a collision when the radar wasn't used the examination would go something like this:

"You had radar on your vessel didn't you?

And that radar was operating, correct?

And you know how to operate the radar?

And radar is caple of detecting other vessels in the vicinity of your own?

Your radar is capable of detecting a vessesl similar to the one you collided with?

Had you been monitoring your radar, you would have detected the other vessel before the collision, correct?

But you weren't monitoring your radar were you?

As a matter of fact, you didn't have your radar on did you?"

That is just off the top of my head, but get the picture?
07-10-2011 09:57 AM
Triquetra I really appreciate the insight of all of you who responded to this, particularly Jackdale's link and nolatom's comment regarding the "vagueness" of the rule. Anytime there is a short, terse rule, I know there are pages of implications behind it. Thank you.
07-07-2011 09:50 PM
Donna_F In the end, everyone is equally responsible for avoiding a collision or an allision (moving object hitting a fixed object). I think the fact that radar is specifically mentioned in the US CFR tells me that if it is installed that a lot of weight is given to it as a means of keeping a lookout. If I was involved in a boating accident, I wouldn't depend on my defense being that I didn't know how to read the radar properly.

Just my opinion.
07-07-2011 05:42 PM
nolatom If you failed to see something your radar, if on, would've seen, then you probably haven't lived up to what Rule 5 says about "all means appropriate to the circumstances".

But if you already saw what radar would've told you was out there (the "bright sunny day"), then you didn't need radar to "help", and likely wouldn't be faulted for not having it on, or using if it was on--the collision was caused by factors other than your lookout.

Different situation, though, if it's restricted viz or obstructed view behind your big jenny while you declined to use radar, and the radar would've seen what you didn't.

Note also that Rules 6 (safe speed rule) and 7 (determining risk of collision) have additional requirements for vessels "fitted with radar". So if you have it, you have to use it, or at least take its capabilities into account.

The article Jackdale linked give much more explanation about all this.

Betcha the courts will find the same principle applies, rules or no, about some of the newer stuff, like AIS, to find out who's out there and communicate with them if in doubt.

The lookout rule is vague on specifics for a reason--they don't want you to have your head stuck in a radar scope (at least in the absence of pea-soup fog) to the detriment of a good visual lookout, no vice-versa either. "Lookout" mean listening too, for signals or foghorns. Or for other vessels talking on the radio (if you have radio, which is whole 'nother topic in the same vein as radar). If you have all this stuff and can't effectively use it all by yourself, then you may be judged to have been short-handed if things went south due to incomplete lookout.
07-07-2011 02:44 PM

Having radar means you should be even more able to prevent a collision so in a way it increases your responsibility as the boat owner.
07-07-2011 10:09 AM
Originally Posted by jrd22 View Post
I have heard that if you have radar and it's not on it will weigh against you if you are involved in an incident. That doesn't answer your question, but there's a lot of gray area in maritime law.
Too true. When I pose that type of question to my buddies at Transport Canada, the response is usually something love "The courts will decide."
07-07-2011 10:08 AM
Rule 5 does not require the installation of radar, but if radar is installed it must be used whenever it would contribute to the quality of the lookout. What are your obligations if radar is installed on your vessel but is not working properly? Rule 5 does not require that mafunctioning radar be used. If the problem is temporary, such as signal blockage caused by a heavy rainstorm, the use of radar can be suspended but not abandoned.

There is a much longer explanation on the site.
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