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Thread: Opinion wanted: Is RADAR mandatory for Cruising, or just get AIS? Reply to Thread
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  Topic Review (Newest First)
11-10-2010 05:08 PM
centaursailor Just spotted this great thread. Was cruising in company to Isle of Mann and heavy fog rolled in. No radar but got updates from following boat using their radar to identify vessels ahead. Will invest in radar when I can afford to.
10-31-2010 06:00 PM
ffiill Where I cruise off the north west coast of Scotland there are few ships and rarely does it get foggy therefore quite happy without radar or AIS.
However if I were sailing the English Channel one of the worlds busiest shipping lanes and noted for fog I would certainly have a mapping AIS which has a radar type display and shows all commercial vessels which by International law will have an AIS transponder.Probably also fit a transponder so they can see me.
Radar remains too expensive for me-despite my boat having been fitted with a Decca system when new 32 years ago but u/s when I got the boat.
10-19-2010 10:59 AM
trisstan87 Tits on a rainbarrel??
10-17-2010 02:44 PM
u4ea There is no electronic gear that is necessary.

GPS shows you some of what is permanently there, but the precision makes it clear that the charts are not correct. Hence, you can't trust it.

Therefore, you also can't trust the charts.

Radar can show you what is actually there. If it is mounted LOW ENOUGH, it can detect things like kelp, logs, even shallow water and reefs (because the waves are different).

When mounted way up the mast, it basically becomes substantially less valuable. Its never useful for long range navigation, because the curvature of the earth, difference in curvature of the beam in different conditions, ...

Sometimes, its very valuable, such as in fog crossing shipping channels.

Safety comes from careful and frequent observation, combined with fore thought and preparation, and -- most important -- respecting the sea and weather rather than the clock.
10-15-2010 06:45 PM
zaliasvejas I sail and live aboard in Maine.
I do not have a radar. Frankly, when fog rolls in, and things get dicy, I rely on my ears and sight first. If I sense a boat near, I call on the radio.
Radar might be helpful, but it takes more than starring at a screen to drive the boat. There are wakes to consider, smell of diesels and sounds of bells. I do not have an AIS system but I am planning on getting one. I race occasionally in Long Island NY and that is where AIS is king. Knowing the direction and speed of the tiny red lights representing a sea going tug with a barge in tow at night can make or break a race.
By far biggest concern for me sailing in Maine is staying off the rocks and lobster pots. In any weather... That requires paying attention to what's ahead and constant vigilance. Somehow radar never came up as a necessary gadget yet.
10-03-2010 09:01 PM
oceanscapt Do you need Radar to cruise safely? No.
Do you need AIS B to cruise safely? No.
Are they nice additions? Yes.

Radar can tell you things that AIS can't. Radar (equipped with ARPA or without) has the virtue of showing you what's going on, abet at a shorter range. You can navigate ranges, enter unknown harbors, check on boat traffic, find low lying atolls, double check distance off and bearings as well as GPS lat/long, and set guard bands for a bit better sleep at night.

Radar costs more than AIS B, may use more power than AIS B, and potentially, has a higher failure rate than AIS B.

The nice thing about AIS is that it can be left on 24/7 and will draw little power. If you want AIS B then the power requirements go up.

If I'm on a boat with radar, I tend to have it on in sea lanes or close to land. If I'm offshore and out of the sea lanes then I tend to have to wake every 6 minutes, do a couple sweeps, analyze the signals and beep if any target shows up in the guard zone, then go back to sleep. Power requirements are considerably less, I get a lot of info from the 6-minute timer, and I don't have to recharge the batteries so often.

One thing to consider is one of those all-in-one systems that seem so popular now. You get radar, GPS, chartplotter, depth, fishing, and some come with AIS. The displays aren't huge and there's a single point failure I find a bit disconcerting, but the cost of one of those is generally less than buying the individual items.
10-03-2010 04:00 PM
rikhall Because of where we cruise (East Coast of Maine, Bay of Fundy) we have RADAR. About $1300.00, mounted on a pole; port, stern.

Because of who else is out there (really really big freighters) we have an AIS receiver. Less than $200.00 and we used an old VHF antenna, also on the RADAR pole on the stern.

Because I like to also know where we are, we have a chart plotter. We also have autopilot for those 10 hour stretches from Eastport to Northeast Harbour. And a hot water heater because the boss likes her shower, and a three burner stove with oven because I like to cook. And a propane furnace, because I like it warm after my shower . . .

And the list goes on. But - to answer the first question, me, I want both RADAR and AIS. But, you may cruise in a totally different location with different circumstances.

10-03-2010 02:02 PM
hooligan6a I sailed around the world on a 29ft. sailboat. There is no way I had the power to run a radar, even if I only turned it on at night. I did not have any electronics that run off the ships battery. Only a hand held GPS. About 90 miles from the Panama Canal, I was run down by a very large ship(600ft.) I could not sail out of his way. He had radar, did me no good. Yes it was in broad day light.
04-20-2010 09:05 PM
tartanDave Sorry everyone I have replaced radar with common sense. I am in no rush to go anywhere and radar will not pick up debris, like logs or shipping containers in the water nor schoals or fishing boats. I feel to many captains push it because their electronic devices say it is ok. Murphy's law says all electronics fail at sea, and if yours has not, it's waiting for the worst.
03-21-2009 08:27 PM
Valiente Yes, that's a good point. Radar is capable of more than just spotting ships and the shore at night, and fiddling around with it in perfect conditions (preferably having had some instruction first so that the interpretation of the display is correct) is a very good way to exploit the technology to its fullest.

I recall seeing in Toronto Harbour the point where aircraft landing at the Toronto Island Airport appeared on the boat's radar screen, and being able to imagine very clearly the "angle" of the beam leaving the radome and heading up and out until it intersected the descending airplane. Tweak the gain in the other direction and you see distant rainstorms.
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