Radar or Not ?

[zeehag]

radar still is more practical than ais--i would buy that--jrc has a unit for under 2kusd.
my garmin 498 has an ais feature--look into that with your gps. you may be surprised.

[barnakiel]

Originally Posted by zeehag

radar still is more practical than ais (...)

OK. But AIS is way easier / faster to interpret what the other ship is doing. So, in heavy traffic areas, those of us who already have a radar may be tempted to get an AIS too!

BTW it looks like maybe Simrad found a way to make a small dome with better resolution - so we might be able to buy very small and much beter resolving radars one day soon. You can read at Panbo about it.

b.

[conachair]

Originally Posted by barnakiel

The radar / AIS, I would not mix the things up. It is not either / or choice. Buy both, if so dictated by your condition. Sure thing on the budget AIS is cheaper, but often it is not good enough.

b.

2 different things, an AIS reciever can produce lots of really useful info for not that much money and very little power. Radar can also produce a mass of useful info, mostly different from AIS but wanting more money and power to do so. Work some more overtime, get both.

Sorry, B, but don't think there is such a clear dividing line as "good enough", if I had more money I'd have so many expensive toys onboard, but don't so live happily (but sometimes a little stressed) without

[IslandHopper]

Originally Posted by Dulls

if you know how to tune a radar you will know its limitations in rain....

Being a Master Class 1 with 30+ years Radar use, i might know a thing or two.....

[Tia Bu]

A little story. Because of this, I stand by my earlier post that I would equip a cruising boat with an AIS first, and a radar second:

Last Fourth of July, I left Narragansett Bay headed for the Long Island Sound. I only had an AIS and chart plotter- no radar. A couple of miles out, I sailed into a zero-visibility fog bank. The Coast Guard began broadcasting security calls about two vessels colliding off Point Judith.

I turned around and went back toward the bay, where the visibility had been good. On the way in, I heard an outbound ferry boat calling "securite". I could see him on my AIS plot. I responded to his security call and altered course to starboard to avoid him. But almost immediately, I could see from the AIS plot that he was altering course to his port and turning onto a collision course. So I called him and requested passing port to port. You could hear the relief in the professional captain's voice when he responded. He clearly knew where I was from his radar. But since I wasn't transmitting AIS information, he didn't know where I was going. I wished I had an AIS transceiver, not just a receiver.

Of course, I also wished I had a radar. But once I got back inshore, where the visibility was much better, I saw one of the boats involved in the collision being towed in. His radar was still turning!

A good many folks are dissing AIS for collision avoidance here. I wonder if they've really worked with it in low visibility situations. It's an inexpensive, easy-to-use tool. In the hands of a relative novice, it can be a very powerful aid.

Unfortunately, in the hands of most pleasure boaters, I fear that radar may not be a very good collision avoidance tool. In fact, it might encourage collisions by enticing people to venture forth on days when they'd be better off staying at the dock. For a video of a tragic radar-assisted collision involving professional seamen:

Ship sinks after collision - YouTube

.

[downunder]

Originally Posted by Tia Bu

A little story. Because of this, I stand by my earlier post that I would equip a cruising boat with an AIS first, and a radar second:

Last Fourth of July, I left Narragansett Bay headed for the Long Island Sound. I only had an AIS and chart plotter- no radar. A couple of miles out, I sailed into a zero-visibility fog bank. The Coast Guard began broadcasting security calls about two vessels colliding off Point Judith.

I turned around and went back toward the bay, where the visibility had been good. On the way in, I heard an outbound ferry boat calling "securite". I could see him on my AIS plot. I responded to his security call and altered course to starboard to avoid him. But almost immediately, I could see from the AIS plot that he was altering course to his port and turning onto a collision course. So I called him and requested passing port to port. You could hear the relief in the professional captain's voice when he responded. He clearly knew where I was from his radar. But since I wasn't transmitting AIS information, he didn't know where I was going. I wished I had an AIS transceiver, not just a receiver.

Of course, I also wished I had a radar. But once I got back inshore, where the visibility was much better, I saw one of the boats involved in the collision being towed in. His radar was still turning!

A good many folks are dissing AIS for collision avoidance here. I wonder if they've really worked with it in low visibility situations. It's an inexpensive, easy-to-use tool. In the hands of a relative novice, it can be a very powerful aid.

Unfortunately, in the hands of most pleasure boaters, I fear that radar may not be a very good collision avoidance tool. In fact, it might encourage collisions by enticing people to venture forth on days when they'd be better off staying at the dock. For a video of a tragic radar-assisted collision involving professional seamen:

.

Good thing the other vessel had radar.

You make an excellent case for RADAR. It is also a great navigational tool many dismiss in the days of chartplotters.

[Hud3]

Originally Posted by Rakuflames

By how close? I mean, you probably moved out of the way in plenty of time, so how do you know you wouldn't have seen the other boat, and/or vice versa, in time? I know a lot of good sailors and very few of them have radar, and none of them are colliding with each other.

I can see it giving someone extra confidence, but dang it's expensive. There's a lot else you could do with that money.

The first time was rounding a point on the Chesapeake Bay. Shoal waters to port, the Bay to starboard, heading north. The menhaden boat was on the same track, headed home to Reedville. I lost sight of him about 1,000 yards away when a very heavy rain squall moved over us. However, I could see him on my radar, steaming along at maybe 20 knots and headed right for me. I had a choice at that point. I could "assume" that the helmsman on the menhaden boat could see me on his radar and change course to avoid running me over, and hold my course. Or, I could take the safe decision and turn to port into the shoal waters, which I did. He drew more than I did, so I knew that would keep him away. Watching on the radar, he never changed course. Visibility was a couple of boat lengths, not enough to make a difference. I never saw him as he went by, thought the radar said he was 200 feet away.

The second time was in the channel between St Vincent and Bequia. Again, a heavy rain squall moved in. This is a busy ferry route between the two islands. I could see the ferries (two of them) coming up on me from ahead and astern. Visibility was maybe 50 feet. Again, I didn't trust the assumption that they would see me on radar and change course, so I moved off the route. Never did see the ferries, the rain was coming down so hard.

Based on my experience with ferries in the Virgin Islands, I never assume they'll change course! Glad to have the radar to help me make good decisions. And even with the very heavy rain, the radar did a great job, properly adjusted.

[monte]

thanks Carina, Ill look into that option you suggested, I liek the idea of a backup vhs antenna. Maybe on the davits. Although I guess it works better if its as high as possible.

[psneeld]

Originally Posted by Tia Bu

A little story. Because of this, I stand by my earlier post that I would equip a cruising boat with an AIS first, and a radar second:

Last Fourth of July, I left Narragansett Bay headed for the Long Island Sound. I only had an AIS and chart plotter- no radar. A couple of miles out, I sailed into a zero-visibility fog bank. The Coast Guard began broadcasting security calls about two vessels colliding off Point Judith.

I turned around and went back toward the bay, where the visibility had been good. On the way in, I heard an outbound ferry boat calling "securite". I could see him on my AIS plot. I responded to his security call and altered course to starboard to avoid him. But almost immediately, I could see from the AIS plot that he was altering course to his port and turning onto a collision course. So I called him and requested passing port to port. You could hear the relief in the professional captain's voice when he responded. He clearly knew where I was from his radar. But since I wasn't transmitting AIS information, he didn't know where I was going. I wished I had an AIS transceiver, not just a receiver.

Of course, I also wished I had a radar. But once I got back inshore, where the visibility was much better, I saw one of the boats involved in the collision being towed in. His radar was still turning!

A good many folks are dissing AIS for collision avoidance here. I wonder if they've really worked with it in low visibility situations. It's an inexpensive, easy-to-use tool. In the hands of a relative novice, it can be a very powerful aid.

Unfortunately, in the hands of most pleasure boaters, I fear that radar may not be a very good collision avoidance tool. In fact, it might encourage collisions by enticing people to venture forth on days when they'd be better off staying at the dock. For a video of a tragic radar-assisted collision involving professional seamen:

.

If everyone had AIS and it was working...and every fixed object had AIS on it...then your AIS screen would look just like a radar with really neat but unecessary info on it. That's the trouble with AIS...doesn't give you all the targets out there but does give good info on some of them.

[Astrid]

I'll second what psneeld says. A properly tuned radar will pick up anything out there large enough to return an echo. One simply needs a good working knowledge of how to use it effectively and have a radar repeater at the helm. AIS is wonderful too, and can provide similar information as radar on any vessel out there that is also equipped with AIS. Unfortunately, in many areas of the world, AIS equipped vessels are not the norm and the vast majority of small boats will not have it and so will not show up on one's own screen. If one is navigating and depending on AIS for collision avoidance at times of minimal visibility, one has to realize that a large proportion of potential obstacles out there will not be registering on your AIS. AIS supplements radar, but does not replace it as the primary means of collision avoidance in poor visibility.

[goboatingnow]

If you navigate in high traffic areas AIS is a godsend and I'd have it before radar. Small boat radar with horizontal resolutions of 7 to 9 degrees is a poor enough device.

My experience is that in any seaway small boat radar will not detect small metallic things like buoys or other yachts. Hell the big Boys will tell you they can't se you on Radar.

Get an AIS transponder then a RADar if you can afford it buy both.

Dave

[Jon Hacking]

Originally Posted by Astrid

... One simply needs a good working knowledge of how to use [radar] effectively ... AIS is wonderful too, and can provide similar information as radar on any vessel out there that is also equipped with AIS. Unfortunately, in many areas of the world, AIS equipped vessels are not the norm ... AIS supplements radar, but does not replace it as the primary means of collision avoidance in poor visibility.

Good summary Astrid. I think we've established that radar & AIS are both useful, & both actually fill slightly different niches. AIS is cheaper, easier to use & takes less power, but can't see small vessels or help you into an anchorage after dark. But using a radar effectively takes considerable skill (note that the vessel that got rammed above had his radar turning).

So the short answer is to get both if you can. Sometimes you need a hammer & sometimes a screwdriver - AIS & Radar are different tools & perform different functions. If you can only get one, then it sort of depends on which you prefer - & this thread shows that's a very personal choice.

Our AIS is on 24/7 & we use it constantly while moving (historically, every 3rd day) while we only turn the radar on perhaps 2x/yr. We have no fog & we rarely sail at night except on passage. But when we need radar, we REALLY need it.

[DotDun]

Since AIS shows <1% of the vessels out there, I prefer radar as my primary tool. I have a passion for avoiding ALL collisions!

AIS is great and one day I will add one to supplement my radar. Contrary to what some have said, my radar is very effective at showing ALL vessels within a mile and larger vessels up to 10-15 miles. I use it very effectively in channels at night as it shows all markers and buoys. And yes, with arpa I get vessel heading, speed, and closest point of approach. I've successfully tracked and deviated course around weather cells 40 miles away.

Yes, radar has a learning curve, but if one doesn't have the ability or willingness to learn it, they shouldn't be at the helm of a vessel. IMO, of course!

[Hud3]

Do you have a stabilizing gyro for your ARPA function? I didn't, and in bouncy conditions the ARPA was very erratic to the point of being useless.

[DotDun]

Originally Posted by Hud3

Do you have a stabilizing gyro for your ARPA function? I didn't, and in bouncy conditions the ARPA was very erratic to the point of being useless.

No, I do not have a gyro. I've noticed in really rough conditions, it (Furuno Digital) takes longer to 'lock on'. I've never had it 'not lock', but have seen it take 3-4 minutes and watched it lose lock, which it eventually reacquired.

Of course, for the point of this thread, regardless of ARPA tracking, it still shows all vessels (unlike AIS).