Radar??? Yes/Maybe/No?? Advice?

[Prairie Schooner]

We have an old radar unit that came with the boat. It’s a monochrome screen, Furuno, which cannot be laced into our new B&G electronics package, 9” plotter at the helm, AIS transponder. In years past we’ve been out in fog on friends’ boats with no radar. We got through it, tooting horns, under sail so we could hear traffic. Our thoughts have been that it was nice to have, but not essential.

Earlier this week we were out for a day sail and had a fog bank roll in. This was our first fog experience with Kismet. It closed in a good deal more than pictured above so we had under 100 hundred yards visibility. We encountered some smaller sail and power boats, none of which were showing AIS. One 34’ picnic boat passed us much closer than I liked. (Confession: I hadn’t yet reconnected the old radar since restepping the mast.) We decided the day was no longer fun and with the chart plotter and local knowledge got back to our mooring without incident. In this case we had the ready option of a safe harbor.

This experience has got us thinking about getting new radar that can be integrated with our electronics. Our earlier experiences were ten years or more ago. Maybe I’ve grown more cautious with age. Maybe when you’re the one in ‘command’ the weight of responsibility is heavier. I feel less cavalier about it than I did back then.

If we’re halfway between Block Island and America (pt to pt about 22 miles) and fog moves in we’d really be on our toes. Our first option is to hook up the old kit and have someone below calling out targets when in the soup. This would require coordinating the old WW2 screen to a chartplotter mirrored on a tablet. Or we could buy new radar from which data can be laid on the helm chart plotter. When we’re double handing this would allow one person to be lookout and make noise.

- How vital do you think a modern radar system is?
- Have you been in low visibility and the radar didn’t give you as much or as reliable information as you’d have liked?
- What factors should we keep in mind if shopping for new radar?

We’re going to the Newport Boat Show tomorrow and will be talking to vendors.

Thanks much,
Jeff


Threads I found somewhat helpful
- https://ericsonyachts.org/ie/threads/ais-vhf-plotter-question.20130/page-2
- https://ericsonyachts.org/ie/threads/radome-installation-at-backstay.19282/#post-149778

 

[paul culver]

- How vital do you think a modern radar system is?

At motor boat speeds in a fog I would say vital. At sail boat speeds, less so. Vigilance, proper horn signalling and running lights are vital. And now we have GPS to keep us apprised of our position in relation to land and marker buoys, as well as AIS to watch out for the really big vessels. I'm more uncomfortable with the wetness of fog than the likelihood of collision.

 

[Loren Beach]

Interesting topic. I find that some of my boating friends nowadays are uninterested in radar, having great faith in AIS.
The problem is, IMHO, that most small fishing skiffs and quite a few larger boats do not transmit AIS data.

Wonderful when you can view AIS in real time, but radar has one significant advantage over it. Radar will show you "reality" whether or not the targets are large or small. Speaking of small, that is still the largest left-over problem... small boats usually have poor radar returns. We sometimes have veritable fleets of smaller boats fishing for salmon in major waterways in the NW. About the only electronics those guys have is a fancy echo sounder.

If you have the choice of avoiding night navigation or during fog, then you can probably choose to have a plotter only.

As usual, it all boils down to your needs and "choices and options."

Personal experience: navigating west in the Straits of Juan de Fuca a few years ago, big patches of fog engulfed us, and radar was marvelous to spot nearby fishing skiffs. They would show as a small target that kept fading in and out, but in the same location. Then the fog would lift and we could confirm a sighting of a 20 foot skiff about 75 yards away. (It always amazes me that those guys never... have a simple and inexpensive radar reflector propped up on their boat, somewhere.

 

[ConchyDug]

I have one it's nice when you need it definitely adds a nice layer of safety/reassurance like AIS/GPS. You could make do without I guess depending on where you are in the world, but it definitely increases situational awareness lowering the pucker factor. I have a Garmin 18 it's the previous generation so not the new HD version. The newer units are super detailed in the data they display when calibrated. You can pick up rain bands as well. I think all the brands are pretty much the same on the radar front.

We get some pretty crazy fog at certain times of the year. With that said the return trip from one of our Fall races can be 150+ miles motoring in the intra-coastal if you don't wanna beat to weather in 5-8' waves. So commercial barge traffic(AIS doesn't tell you he is pushing 600 feet of barges) and fog would make that a bit tedious without radar. We also have lots of strange commercial vessels/structures in the Gulf associated with oil&gas and their scale is usually not noted on charts. I've been in fog so thick you could barely see the front of the boat and the radar picked up all the channel markers no problem so it kinda helps with punching into "IMC" overlayed with an updated digital chart . I've also had it drop offline(corroded terminal) in similar conditions and it was slow going after that.

Another consideration, I have a backstay radar mount and forward visibility is fine, mounted 15' ish off the water. I'm not a fan of the mast mount position it adds a pretty sweet snag point for headsails. A friend who owns a rigging shop made enough money reinstalling broken mast mounts that he advised against them. It's an opinion I'd figure I'd throw out there. Attached a grainy photo of the backstay mount.

 

[Christian Williams]

To me radar is like a dodger--live without it if you can. Here, I can. In Maine, I'd have radar.

Just a couple of years ago we took a 60-footer Mt. Desert to Newport, and the fog was so thick my job was shouting lobster pots at the bow as we left port. The owner sat in front of his radar screen the entire voyage, no sleep at all, as we rarely had even half a mile visibility. Absolutely could not have made his tight schedule without radar.

 

[windblown]

I’ve been having similar conversations with the admiral. We’re on Lake Ontario, and have only cruised for a few days at a time, so we’ve been able to adjust our plans for weather conditions. Should we invest in radar before thinking about longer cruises? As a kid, I remember getting caught in a couple of fog banks that came in very fast. Very few power boats here transmit AIS, and they’re often the scariest (least experienced, most aggressive) skippers in good weather, so I’d hate to be headed in to port with a couple dozen of them. If we were to add radar, I’d probably want to mount it on the back stay with something like scanstrut’s https://www.scanstrut.com/marine/sa...ng-radar/backstay-leveller/aft-leaning/lmb-a1. That almost doubles the cost of adding radar. several years ago, I started our NMEA network with a 7” B&G Zeus3 MFD. I’ve regretted that investment since, because It has not been as compatible with other brands we’ve added to the network as I had hoped. And I’ve found B&G service and support to be less than helpful. It’s pretty, but it’s too expensive to be just a chartplotter and audio controller. Have others crossed B&G mfd’s with other radar brands successfully?

 

[Loren Beach]

A friend with a 32-3, has a radar mounted on a Garhauer post on one side of the transom, and we did not feel that we had any need at all for any other type/style of mounting on trips up n down the WA coast. That backstay gimbal scheme was aimed at boats planning on being on one tack for hours or days at a time, IMHO.
Smaller boats like ours are gonna rock n roll a bit, but nothing that will not let the radar average out the returns over the width of the beam.
A large part of the appeal of radar is use in more protected waters where so many small boats are wandering around. Out to sea the targets are larger and will generally have an AIS return to look at. And, out at sea, there will be 95% less targets to watch for.
(Opinions rendered at discount Viking prices, usually free on Fridays.)

 

[Loren Beach]

On the subject of brand, I did talk to the mgr of our local marine electronics company last week. Our 9" Lowrance combo plotter/radar is a decade old and I was curious about a someday replacement. Our digital antenna is still "current" technology, but software keeps evolving. He would recommend the B&G unit for a sailor now, but either the Simrad or the Lowrance would still do for general sailing/boating. All of these are very similar but their software varies with their intended market. Same parent company.
No reason for us to change at this point.
And then, before any of those concerns come into focus, you first have to decide on mounting and which models have a chip door with a permanent magnet that will disrupt your steering compass (minimum of 19" to over 30" away depending on model/brand). That was the reason we chose the Lowrance over a very similar Simrad, last time around.
It helps to have a sort of formal "decision tree" , heading into this upgrade. IMHO. And, YMMV.

 

[paul culver]

Of course it would be nice to get a heads up that fog was likely to set in and maybe you should head back from your day sail a little earlier than expected. You can get that warning by noting the difference in wet/dry bulb thermometer temperatures over time. From the differences you can get the dew point and the rule of thumb is that fog sets in when air temp and dew point are within 5 degrees F. of one another. If you (or your STEM-inclined kid) have been graphing your results along the way the trend line will indicate how quickly things might be developing. Finish off your remaining beers tied up safely at dockside.

 

[Pete the Cat]

I think if you sail in fog, even occasionally where there are other boats, you need radar--there are too many idiots out there relying on their luck, chartplotters and AIS. I have an ancient Simrad CRT unit that I love for its clarity and function on my Tartan and I have a brand new Furuno that I think is acceptable, but less precise, on my Ericson. Both are on poles off the stern because my experience is that where you REALLY want radar is in close passing and putting the radar up high does not really give you much range (I know how to do the math it is just that most of the safety issues are close aboard--buoys, passages and channels--close resolution is much more important than trying to see out 16 miles). I have described my opinion of any reliance on AIS as poor seamanship, and that doing so is likely to kill some folks who rely on it, if it has not already. I am actually irritated when I have the AIS (I have AIS inbound) alarm for a 27 foot sailboat that only has the most remote chance of contact--because the plotters cannot account for leeway and windshifts.. I refuse to put outboat AIS on either of my boats as I think it is on the way to becoming such an annoyance (because so many small recreational boats are now using it outbound) that folks will ignore the alarms because they are ubiquitous in crowded areas. Also, most of the traffic in Maine is lobster fishermen and they do not use AIS at all and, trust me, they are everywhere and rely on radar. I consider AIS a technology, at this point, presents as much danger to recreational boaters (very important for ocean passages and very large vessels) as it does safety. I do not like integrated units I have used on deliveries with others--maybe they are iimproving recently---but the ones I have used just seem to try to cram too much information into too small and too cluttered a screen--the integrated radar units seem to have less resolution and fine tuning capability---which can been important in some situations. (like rain and differentiating buoys from boats, etc). But I confess to being very very conservative when it comes to new technology. And someone needs to buy the stuff and show us what works. I have found the latest is not always the greatest.

 

[Christian Williams]

Yeah, AIS is best if you plan to go to sleep. If you plan to go to sleep daysailing, well, it is better than nothing (That's a joke).

One value for me locally is estimation of conflicts with commercial vessels when crossing shipping lanes. I'm still not good at judging that five miles away, and the AIS gives a reliable answer (Closest Point of Approach and Time to it). Formerly I'd say "hold your course until we're closer"--which freaked everybody out for the next half hour.

 

[Prairie Schooner]

Thanks everyone who has weighed in. Your comments have been very helpful. We were at the boat show today and ended up talking to the same folks who had installed our current round of electronics. We're taking some initial steps toward new radar.

This is somewhat like discussing how much insurance to buy, weighing the likelihood of mishap and potential consequences against the cost of insulating yourself from them. Our schedules are generally flexible enough that we can delay a departure a day or two to avoid foggy weather. In my experience where we are, fog is only likely to interrupt plans a couple times a season. We have AIS to aid us. We will always be at least double handing so one person can be lookout. We're comfortable working the boat under sail so we can hear better. BUT, if we're halfway into a long passage and fog rolls in, we are indeed putting our fate in the hands of "idiots". So, though the odds of disaster are low, the results of a collision could be fatal. We've decided we need radar.

@Pete the Cat Ray, your preference for your old CRT system is interesting. I wish we'd had more experience with ours. It's probably original to the boat, or nearly that old. I appreciate your comments about clarity. We could just keep the setup we currently have. Yet, I'm imagining us in fog, I'm driving, Donna is at the nav table watching radar. She would have a tablet mirroring the chartplotter, trying to reconcile what she sees on radar with features on the chart, and calling bogeys up to me. I would be trying to coordinate her remarks with what I sense around me and see on the plotter. It seems like the clarity that might gained by watching the old school radar would be lost in the parlor game trail of communication. Once we have the new gear, we would definitely have to go out regularly in good weather for IFR practice.

@windblown Deborah, we're just going to stick with B&G and not try to mix systems. We had our current system all installed by a marine electronics company and they warranty their work. At the beginning of this year we had wind data drop out and they were Very responsive in getting techs out to work on it. It took maybe four visits to chase down the problems, but that was on their dime. It turns out the one piece of old equipment we kept, a Raymarine wheel pilot, didn't talk as well with our system as hoped. The other ghost was a faulty connector. The initial install was expensive, but we're very pleased with the service from local Cay Electronics. We haven't had to deal direct with B&G.

@Christian Williams Chris, Your k.i.s.s. common-sense approach keeps me grounded. I've been on lobster buoy duty in Maine, some at night and some in fog. It's exhausting. We hope to work our way that far north as we spread our wings with Kismet. I wasn't giving enough thought to what it would be like in those waters. Over a decade ago I was on crew completing an Annapolis>Newport race one pre-dawn with some barge and other miscellaneous traffic, no radar, no AIS. It was a chaos of sparkly lights to me. There were some former Navy black shoes on board who were able to read it like the back of their hand. I'm not that experienced and never will be. I'm sure we don't have anything like the commercial traffic you must in the LA area.

@paul culver Paul, Will you ride shotgun as our weather officer? Actually, I want to become more of a student of weather. Mariners depend so much on it. I didn't even know wet/dry bulb thermometers were a thing.

@ConchyDug Doug, Reducing 'pucker factor' is something definitely on our minds. There were five offshore wind turbines installed here a few years ago and more on the way. Our experience here is probably going mirror yours more in the future.

@Loren Beach Loren, Alas, our plotter is mounted a scant 10 inches from the binnacle compass. We are currently storing it below when not sailing. Next time I hook it up I'm going to make a point of moving it toward and away from the compass and seeing how much deviation ensues. We're stuck with it, but I could always remove the magnet and devise a velcro strap or something.

Mount Location: Our current radar dome is mounted on the mast. That's where we're planning on putting this one, because of economic constraints. However, if I were starting from scratch, I'd mount it on the stern. For the sailing we're doing, finding possible collision targets in poor visibility is the high priority, not long range hazards or features. I'm going to ask the tech about this. Maybe there's a way it can be mounted to pick up a little more near-proximity data. I'm wondering if it could just be tilted down a very little bit.

Again, thanks all.
Jeff

 

[Pete the Cat]

Yeah, AIS is best if you plan to go to sleep. If you plan to go to sleep daysailing, well, it is better than nothing (That's a joke).

One value for me locally is estimation of conflicts with commercial vessels when crossing shipping lanes. I'm still not good at judging that five miles away, and the AIS gives a reliable answer (Closest Point of Approach and Time to it). Formerly I'd say "hold your course until we're closer"--which freaked everybody out for the next half hour.

I agree. AIS is really valuable for estimating and avoiding conflicts with large ships. I have the same difficulty estimating closest point on those big guys who are often moving at wildly different speeds. But the greatest terror I have these days in low visibility situations is some amateur dufus trucking along at speed relying solely on his AIS and a chartplotter. For an old guy, it is a new hazard. I think the marine media is adequately afraid of their advertisers so they have not really highlighted this potential downside of the technology.

Thanks everyone who has weighed in. Your comments have been very helpful. We were at the boat show today and ended up talking to the same folks who had installed our current round of electronics. We're taking some initial steps toward new radar.

This is somewhat like discussing how much insurance to buy, weighing the likelihood of mishap and potential consequences against the cost of insulating yourself from them. Our schedules are generally flexible enough that we can delay a departure a day or two to avoid foggy weather. In my experience where we are, fog is only likely to interrupt plans a couple times a season. We have AIS to aid us. We will always be at least double handing so one person can be lookout. We're comfortable working the boat under sail so we can hear better. BUT, if we're halfway into a long passage and fog rolls in, we are indeed putting our fate in the hands of "idiots". So, though the odds of disaster are low, the results of a collision could be fatal. We've decided we need radar.

@Pete the Cat Ray, your preference for your old CRT system is interesting. I wish we'd had more experience with ours. It's probably original to the boat, or nearly that old. I appreciate your comments about clarity. We could just keep the setup we currently have. Yet, I'm imagining us in fog, I'm driving, Donna is at the nav table watching radar. She would have a tablet mirroring the chartplotter, trying to reconcile what she sees on radar with features on the chart, and calling bogeys up to me. I would be trying to coordinate her remarks with what I sense around me and see on the plotter. It seems like the clarity that might gained by watching the old school radar would be lost in the parlor game trail of communication. Once we have the new gear, we would definitely have to go out regularly in good weather for IFR practice.

@windblown Deborah, we're just going to stick with B&G and not try to mix systems. We had our current system all installed by a marine electronics company and they warranty their work. At the beginning of this year we had wind data drop out and they were Very responsive in getting techs out to work on it. It took maybe four visits to chase down the problems, but that was on their dime. It turns out the one piece of old equipment we kept, a Raymarine wheel pilot, didn't talk as well with our system as hoped. The other ghost was a faulty connector. The initial install was expensive, but we're very pleased with the service from local Cay Electronics. We haven't had to deal direct with B&G.

@Christian Williams Chris, Your k.i.s.s. common-sense approach keeps me grounded. I've been on lobster buoy duty in Maine, some at night and some in fog. It's exhausting. We hope to work our way that far north as we spread our wings with Kismet. I wasn't giving enough thought to what it would be like in those waters. Over a decade ago I was on crew completing an Annapolis>Newport race one pre-dawn with some barge and other miscellaneous traffic, no radar, no AIS. It was a chaos of sparkly lights to me. There were some former Navy black shoes on board who were able to read it like the back of their hand. I'm not that experienced and never will be. I'm sure we don't have anything like the commercial traffic you must in the LA area.

@paul culver Paul, Will you ride shotgun as our weather officer? Actually, I want to become more of a student of weather. Mariners depend so much on it. I didn't even know wet/dry bulb thermometers were a thing.

@ConchyDug Doug, Reducing 'pucker factor' is something definitely on our minds. There were five offshore wind turbines installed here a few years ago and more on the way. Our experience here is probably going mirror yours more in the future.

@Loren Beach Loren, Alas, our plotter is mounted a scant 10 inches from the binnacle compass. We are currently storing it below when not sailing. Next time I hook it up I'm going to make a point of moving it toward and away from the compass and seeing how much deviation ensues. We're stuck with it, but I could always remove the magnet and devise a velcro strap or something.

Mount Location: Our current radar dome is mounted on the mast. That's where we're planning on putting this one, because of economic constraints. However, if I were starting from scratch, I'd mount it on the stern. For the sailing we're doing, finding possible collision targets in poor visibility is the high priority, not long range hazards or features. I'm going to ask the tech about this. Maybe there's a way it can be mounted to pick up a little more near-proximity data. I'm wondering if it could just be tilted down a very little bit.

Again, thanks all.
Jeff

I generally use my radar to make major deviations to avoid even getting close to folks if that is possible--early and apparent avoidance is my advice to crew. I simply do not trust small boats to maintain course and heading. Large ships are more reliable. We have to make close approaches here in Maine through narrow passages and I like to do my navigation strategy and planning below and early, not spontaneously at the helm. I will go to the helm only when they are really close and I know their likely direction and ready for visual confirmation. I suppose I make more trips to the chart table than many folks--but that is a trade off for safety imho. Offshore and at night I do almost all my navigation and helming from the chart table (my below deck autopilot has a remote repeater--technology that I consider important for offshore at night). There is little value to me to be staring into the dark (vessel lights give you only gross information about direction and speed at night) or staring into a dense fog bank from the helm. I have a chartplotter at the helm, but would never rely on AIS in a close passing situation in one of the passages--radar or actual eye contact is essential to me. Maybe the MFDs have improved, but I delivered a yacht from Annapolis to Maine a year ago and the MFD with radar overlay was difficult to read (adjusting for glare and fine tuning was hard when pitching at the helm was frustrating--I felt like I was making it up as I was going along). I agree that folks really need to practice with this technology before they have to use it. My new Furuno unit has a lot of "automatic" tuning features that I would prefer were manual. My ancient Simrad lets me do the fine tuning with control knobs, not obscure hidden menus. Maybe if you only use radar occasionally you would be better off with an "automatic" unit. I don't like them.

 

[Prairie Schooner]

. . .
. . . Offshore and at night I do almost all my navigation and helming from the chart table (my below deck autopilot has a remote repeater--technology that I consider important for offshore at night). There is little value to me to be staring into the dark (vessel lights give you only gross information about direction and speed at night) or staring into a dense fog bank from the helm. . . .

Ah, this is an important difference I hadn't thought of, Ray. We don't have a reliable or integrated auto pilot. One of us has got to be at the helm.

I appreciate your comments about the pitfalls of the technology. It gives some focus for the training we'll have to do. I'd be interested in also hearing how other folks integrate radar into their navigating and steering. What works well? Where are the holes in the technology? What do you trust, not trust?

 

[Teranodon]

I installed radar last year, mostly because my wife kept asking for it as a safety feature. I have never used it "in anger" but I like to turn it on just for fun. I went with Garmin because it connects seamlessly to my 9" chartplotter and AIS VHF radio. I chose the Fantom model which does Doppler. Approaching targets appear in one color (I chose red), receding ones in another (green). This is really pretty cool/impressive. I believe all the major manufacturers offer this feature. A bizarre note: after a fairly laborious installation, I couldn't get it to work. Had to send the giant package back to Garmin. Turns out it was not connected to power inside the dome! This changed my opinion of the company, so I'm passing it on.

 

[David Grimm]

I say go with radar and AIS. Radar especially if you plan on sailing anywhere north of the NY harbor. A few months ago we pulled out of Montauk in rout to Block Island in 35 knot winds, big seas and heavy fog. As we roumded the tip of Montauk the fog was getting really bad and I realized I never turned the AIS on. Quick run below deck past my wife barfing in the head I hit the power button and set to coastal... Beep Beep Beep. Wtf? Why won't this stop beeping...... ohhh shit!!! Ran up on deck and you could barely see the front of the boat. Then to my surprise about 200 feet off the starboard bow appeared a center console fishing boat! Close call! I flipped the radar on and between both I could see my surroundings. Including the Coast Guard vessel far off the port side that would eventually hail us on the vhf to let us know that they were out here with us monitoring the high sea conditions due to tide vs. wind effect. They informed us that the conditions would improve as we got closer to Block but if we needed assistance they were there.

My advice is to frequently play with the radar in clear conditions so you become familiar with the controls and how reality compares to what's on the screen. I have a Garmin 942xs and HD Radar thats a few years old now. Works well. Works even better if you turn it on early!

 

[wynkoop]

I am a professional mariner. I have worked as a bridge officer on large freighters, and as captain of various head boats and day charter boats for the past few years. Many of the boats I am currently running in NY harbor have combined plotter/radar displays. I much prefer having one screen for the radar and another for the plotter. That way if one screen goes out I do not lose two tools. The sad part is on sailboats often there is not room at the helm for one of the two, much less both. My E27 for instance has no plotter or radar.

I currently captain a 50 foot Jeanneau in charter service and she has the radar below, pretty much useless to me, and a chart plotter at the helm.
If the only consideration were FOG I think I would want a radar at the helm and have the chart plotter below. The radar will show me land, buoy's, and many, but not all other vessels. When I was in school they taught us that the Coast Guard considers a safe speed to be one where you can stop in half the distance you can see. In fog I slow down based on the visibility. If it gets thick enough I stop. Another captain I know suggested to me holding position right next to a buoy, and on the outside of the channel if your draft allows. I find that a good option if you can not see.
Last night I nearly collided with a jet ski. The jet ski had no lights, was all black and the rider was dressed head to toe in black. That was on a clear night and the only reason I saw him was he passed in front of a light which allowed me to catch his silhouette. Now think about moving in a fog where you can not see 10 feet. Yes a jet ski you would hear, but maybe not another sailboat motoring slow. Not everyone sounds fog signals like they should, sadly.

I whole heartedly agree that you need to use your tools, AIS, GPS, RADAR when it is clear to be proficient in it's use in poor conditions. On boats I run that have chart plotters, AIS, and radar I run all three so I know how things work and how things should look. Being able to look at the radar, then look out and see the coast, buoy, or boat where the radar says it should be gives you confidence in your equipment and the ability to know if it is acting up when in the soup.

As others have said do not trust AIS. Some very big vessels are not required to carry it. Most small vessels do not have it, & I know of some large vessels that frequent NY harbor that have flakey AIS systems. Remember by the rules you are to proceed at a safe speed for the prevailing conditions, and sadly too many people on the water think radar and chart plotters are magic. They are not. They are tools. It really is not safe to proceed any faster than you would if you did not have the tools.

 

[bsangs]

We're getting radar this offseason, to go along with our existing AIS. Have nothing to add here, but just wanted to chime in and say this is a fantastically informative thread that I've made sure to bookmark for future reference. Thanks for sharing so much.

 

[Prairie Schooner]

I installed radar last year, mostly because my wife kept asking for it as a safety feature. I have never used it "in anger" but I like to turn it on just for fun. I went with Garmin because it connects seamlessly to my 9" chartplotter and AIS VHF radio. I chose the Fantom model which does Doppler. Approaching targets appear in one color (I chose red), receding ones in another (green). This is really pretty cool/impressive. I believe all the major manufacturers offer this feature. A bizarre note: after a fairly laborious installation, I couldn't get it to work. Had to send the giant package back to Garmin. Turns out it was not connected to power inside the dome! This changed my opinion of the company, so I'm passing it on.

Thanks Stefan. This helped me as we hone in on which model we get. We're kind of locked into the B&G ecosystem already. They have two 20" models and the + model has the features you're describing. I realize we're spending a chunk of change on something we will rarely need. (shrug emoji) A friend would use his radar in races to tell whether he was gaining distance on other competitors.

 

[Prairie Schooner]

I am a professional mariner. I have worked as a bridge officer on large freighters, and as captain of various head boats and day charter boats for the past few years. Many of the boats I am currently running in NY harbor have combined plotter/radar displays. I much prefer having one screen for the radar and another for the plotter. That way if one screen goes out I do not lose two tools. The sad part is on sailboats often there is not room at the helm for one of the two, much less both. My E27 for instance has no plotter or radar.

I currently captain a 50 foot Jeanneau in charter service and she has the radar below, pretty much useless to me, and a chart plotter at the helm.
If the only consideration were FOG I think I would want a radar at the helm and have the chart plotter below. The radar will show me land, buoy's, and many, but not all other vessels. When I was in school they taught us that the Coast Guard considers a safe speed to be one where you can stop in half the distance you can see. In fog I slow down based on the visibility. If it gets thick enough I stop. Another captain I know suggested to me holding position right next to a buoy, and on the outside of the channel if your draft allows. I find that a good option if you can not see.
Last night I nearly collided with a jet ski. The jet ski had no lights, was all black and the rider was dressed head to toe in black. That was on a clear night and the only reason I saw him was he passed in front of a light which allowed me to catch his silhouette. Now think about moving in a fog where you can not see 10 feet. Yes a jet ski you would hear, but maybe not another sailboat motoring slow. Not everyone sounds fog signals like they should, sadly.

I whole heartedly agree that you need to use your tools, AIS, GPS, RADAR when it is clear to be proficient in it's use in poor conditions. On boats I run that have chart plotters, AIS, and radar I run all three so I know how things work and how things should look. Being able to look at the radar, then look out and see the coast, buoy, or boat where the radar says it should be gives you confidence in your equipment and the ability to know if it is acting up when in the soup.

As others have said do not trust AIS. Some very big vessels are not required to carry it. Most small vessels do not have it, & I know of some large vessels that frequent NY harbor that have flakey AIS systems. Remember by the rules you are to proceed at a safe speed for the prevailing conditions, and sadly too many people on the water think radar and chart plotters are magic. They are not. They are tools. It really is not safe to proceed any faster than you would if you did not have the tools.

Lots of good stuff there, Brett. Thank you!