C08
Well-Known Member
Which to buy, coastal and XChannel sailing?
AIS Transponder or Radar or Active Radar Transponder
- Thread starter C08
- Start date
LadyInBed
Well-Known Member
What is your budget?
Poey50
Well-Known Member
These would be my order of priority depending on funds ... best to start at 2.
1. AIS receiver
2. AIS transponder
3. Echomax dual band
4. Radar
1. AIS receiver
2. AIS transponder
3. Echomax dual band
4. Radar
srm
Well-Known Member
I started with radar as it is also a nav aid, then added an active radar transponder. That was before AIS transponders were within price range. Now have all three.
Would now go for AIS transponder and Active Radar transponder with dual bands, but if budget will stretch add radar but this aid is only of any use if you take the time to learn how to use it .
Would now go for AIS transponder and Active Radar transponder with dual bands, but if budget will stretch add radar but this aid is only of any use if you take the time to learn how to use it .
LadyInBed
Well-Known Member
I would only bother with RADAR if you are happy with sailing in fog.
Nowadays my first choice is AIS Transceiver, so that other small boats with only a AIS Receiver can see you if you have poor Viz conditions.
If you can afford to get a RADAR as well, then get both, as they do do different job.
Nowadays my first choice is AIS Transceiver, so that other small boats with only a AIS Receiver can see you if you have poor Viz conditions.
If you can afford to get a RADAR as well, then get both, as they do do different job.
Javelin
Well-Known Member
My three best things I have on my boat.
Autohelm with radio control
Harken Furler
AIS Tranceiver (transponder)
Probably a pain in the Solent but sailing too and from Holland/Belgium/France/Eastcoast UK its been a godsend with ships calling me up direct via dsc before I've even realised they were an issue.
Also it won't be long until Trinity House replaces physical bouyage with virtual ones.
I've sinced ditched my radar as in five years I've never had to use it.
Autohelm with radio control
Harken Furler
AIS Tranceiver (transponder)
Probably a pain in the Solent but sailing too and from Holland/Belgium/France/Eastcoast UK its been a godsend with ships calling me up direct via dsc before I've even realised they were an issue.
Also it won't be long until Trinity House replaces physical bouyage with virtual ones.
I've sinced ditched my radar as in five years I've never had to use it.
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prv
Well-Known Member
I'd put the active radar transponder at the bottom of the list. They're still a good piece of kit, but I get the impression that the number of vessels out there operating solely on radar without an AIS display is now pretty limited, and so an AIS transmitter that will be visible and useful to a much wider range of vessels has to take priority.
AIS receive capability has to be at the top of the list, just because - assuming you already have a plotter - it's the cheapest and easiest to fit and the most immediate use to you under normal good-visibility conditions. You mention cross-Channel, and being able to monitor CPAs on all the ships coming towards you down the lanes will make a very big difference to how you manage that crossing. Of course, AIS transmitters also include receivers, so a standalone receiver would be a waste of money and effort if you anticipated adding a transmitter soon afterwards.
So now we just need to put radar and AIS transmit in order. This I'm less sure about. It comes down to whether you think you'll end up sailing in reduced visibility much. In fog, the best setup by far is AIS and radar combined, but if I had to choose one I'd take a modern radar (with effective MARPA) over AIS every time. I've actually tested this, inadvertently - due to equipment failures I've found myself once operating in thick fog with AIS receive and a radar that mostly worked but occasionally cut out for a few minutes, and once in thick fog with good radar but AIS that barely worked all day. I was a lot more comfortable in the second situation, despite the failure being more complete.
Radar of course will spot almost anything, from floating obstructions to small craft without AIS transmitters to larger vessels whose transmitter isn't operating for some reason. And it's useful for navigation too - if you're within the radar horizon of land you can do a quick scan, check the overlay against the chart underneath, and be sure that the little boat symbol really is in the right place. Sure, in this day and age it's pretty unlikely that it would be wrong, but the principle of cross-checking navigational sources is still a thing and I for one feel more confident entering a Channel Islands rock garden with two independent inputs to the system (and the transits, of course!).
On balance, I think I'd put radar above AIS transmit because of its independence and its versatility. The AIS transmitter relies on various external systems, and only does one job - making you visible to others, who should in any case have other means of detecting you. But depending on equipment price and the way they intended to use their boat, I could see someone making the opposite call.
So in summary, I'd say:
1. AIS Receive
2. Radar
3. AIS Transmit
4. Radar Transponder.
Pete
AIS receive capability has to be at the top of the list, just because - assuming you already have a plotter - it's the cheapest and easiest to fit and the most immediate use to you under normal good-visibility conditions. You mention cross-Channel, and being able to monitor CPAs on all the ships coming towards you down the lanes will make a very big difference to how you manage that crossing. Of course, AIS transmitters also include receivers, so a standalone receiver would be a waste of money and effort if you anticipated adding a transmitter soon afterwards.
So now we just need to put radar and AIS transmit in order. This I'm less sure about. It comes down to whether you think you'll end up sailing in reduced visibility much. In fog, the best setup by far is AIS and radar combined, but if I had to choose one I'd take a modern radar (with effective MARPA) over AIS every time. I've actually tested this, inadvertently - due to equipment failures I've found myself once operating in thick fog with AIS receive and a radar that mostly worked but occasionally cut out for a few minutes, and once in thick fog with good radar but AIS that barely worked all day. I was a lot more comfortable in the second situation, despite the failure being more complete.
Radar of course will spot almost anything, from floating obstructions to small craft without AIS transmitters to larger vessels whose transmitter isn't operating for some reason. And it's useful for navigation too - if you're within the radar horizon of land you can do a quick scan, check the overlay against the chart underneath, and be sure that the little boat symbol really is in the right place. Sure, in this day and age it's pretty unlikely that it would be wrong, but the principle of cross-checking navigational sources is still a thing and I for one feel more confident entering a Channel Islands rock garden with two independent inputs to the system (and the transits, of course!).
On balance, I think I'd put radar above AIS transmit because of its independence and its versatility. The AIS transmitter relies on various external systems, and only does one job - making you visible to others, who should in any case have other means of detecting you. But depending on equipment price and the way they intended to use their boat, I could see someone making the opposite call.
So in summary, I'd say:
1. AIS Receive
2. Radar
3. AIS Transmit
4. Radar Transponder.
Pete
MAURICE
Well-Known Member
1.Radar
2.Transponder
Wouldnt bother with the other 2 have seen a large ship which did not have an AIS signal but able to pick up and later see clearly on RADAR. Not all boats/ships have AIS and if they do may not work or have them turned off.
If you can afford have both
2.Transponder
Wouldnt bother with the other 2 have seen a large ship which did not have an AIS signal but able to pick up and later see clearly on RADAR. Not all boats/ships have AIS and if they do may not work or have them turned off.
If you can afford have both
Graham376
Well-Known Member
We've had radar for 20+ years and wouldn't want to be without it. Never felt the need for AIS or transponder.
Iliade
Well-Known Member
I have had AIS receive for a few years now and it is a godsend on a bright sunny day let alone a dark stormy night! I would like tx but consider that far less important for cross-channel sailing. My system is a Standard Horizon VHF/AIS talking to a Garmin 451s.
I recently bought a boat that came with an old radar and it is superb in fog, especially for spotting out of position buoys, but does need operating skills (not to be underestimated) and is a lot more power hungry than AIS RX. I'm told it does not help others to see you unless they are operating radar guided missiles.
For navigation I still prefer the GPS though! ;0)
I strongly suspect that peoples' views on the matter are greatly affected by where they sail - Crossing the Channel can be like trying to cross the M25 some days.
I recently bought a boat that came with an old radar and it is superb in fog, especially for spotting out of position buoys, but does need operating skills (not to be underestimated) and is a lot more power hungry than AIS RX. I'm told it does not help others to see you unless they are operating radar guided missiles.
For navigation I still prefer the GPS though! ;0)
I strongly suspect that peoples' views on the matter are greatly affected by where they sail - Crossing the Channel can be like trying to cross the M25 some days.
pvb
Well-Known Member
I reckon many more ships monitor radar than monitor AIS (integrated displays are still not common). So an active radar transponder would give slightly better protection than an AIS transceiver.
johnalison
Well-Known Member
There is really no exact answer to the question and it mainly comes down to budget, as said. I started with radar in 2000 and have been grateful for having it. Sailing in northern European waters for about three months each year after retiring, I probably needed radar about once every two or three years, but when I used it it was a godsend. Along with AIS it allows you to set out when there is some possibility of poor visibility, when previously you would have stayed in harbour.
AIS I have in use every time I go out, including class B. It adds greatly to the enjoyment of passage-making and is a worthwile back-up in case of fog, but I would not rely on it to the same extent as radar unless I was constrained by budget, and then still be unwilling to set out when fog is likely.
AIS I have in use every time I go out, including class B. It adds greatly to the enjoyment of passage-making and is a worthwile back-up in case of fog, but I would not rely on it to the same extent as radar unless I was constrained by budget, and then still be unwilling to set out when fog is likely.
lw395
Well-Known Member
None of these things are essential to sail the English Channel.
None of them will make up for being an idiot or be a substitute for a good lookout and common sense.
I'd go without all of them if the choice was a half decent crew who'd enable me to get some kip on a cross channel.
Maybe that tilts a bit the other way for short crossings at the Dover end. Maybe not!
I think an AIS transponder is the most versatile generally, but a radar is the only thing which is totally self contained and works against land as well as ships etc.
Radar uses a fair bit of power and costs enough that it would be daft not to have class B AIS as well for any yacht that I can imagine?
None of them will make up for being an idiot or be a substitute for a good lookout and common sense.
I'd go without all of them if the choice was a half decent crew who'd enable me to get some kip on a cross channel.
Maybe that tilts a bit the other way for short crossings at the Dover end. Maybe not!
I think an AIS transponder is the most versatile generally, but a radar is the only thing which is totally self contained and works against land as well as ships etc.
Radar uses a fair bit of power and costs enough that it would be daft not to have class B AIS as well for any yacht that I can imagine?
Graham376
Well-Known Member
Particularly as ships can filter out class B AIS. As more people leave AIS transmitting when in marinas, the more likely this is likely to happen to de-clutter screens.
Allan
Well-Known Member
We had Radar and AIS transponder fitted in 2016. Every time we start a new trip, we turn on the Radar, to check it's ok and familiarise ourselves with the controls again. The AIS stays on 100% of time. We've sailed a little over 30,000nm since 2016. Apart from the tests, mentioned above, the Radar has been used twice, both times in thick fog and both times we found the plotter and AIS would be good enough. The AIS is used most of the time.
On my previous boat I had Radar and used it to identify and avoid ships crossing the western English channel. After fitting an AIS receive only, I used that on subsequent crossings.
I would go for AIS transponder every time. If you include power consumption in the calculation Radar drops even further down the list.
Allan
On my previous boat I had Radar and used it to identify and avoid ships crossing the western English channel. After fitting an AIS receive only, I used that on subsequent crossings.
I would go for AIS transponder every time. If you include power consumption in the calculation Radar drops even further down the list.
Allan
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Roberto
Well-Known Member
They have mixed purposes, from collision avoidance to navigating in restricted visibility.
Coastal/channel collision avoidance in normal weather conditions and a lot traffic: Ais receiver if possible, transponder better. I found using radar with too many targets is too risky, some ships are going so fast they are the real danger even before being displayed on the screen, also one needs someone being constantly looking at the screen and able to intepret it. Definitely cross- check ais positions with radar targets, some surprises to be had.
Restricted visibility coastal navigation --> radar, also useful at night for unlit buoys or obstructions
Offshore -though not the OP question- radar target enhancer every time, other equipments way below.
(I have all of them, ended up using them as above).
Coastal/channel collision avoidance in normal weather conditions and a lot traffic: Ais receiver if possible, transponder better. I found using radar with too many targets is too risky, some ships are going so fast they are the real danger even before being displayed on the screen, also one needs someone being constantly looking at the screen and able to intepret it. Definitely cross- check ais positions with radar targets, some surprises to be had.
Restricted visibility coastal navigation --> radar, also useful at night for unlit buoys or obstructions
Offshore -though not the OP question- radar target enhancer every time, other equipments way below.
(I have all of them, ended up using them as above).
prv
Well-Known Member
Bear in mind that unless the OP's buying an old radar on eBay, anything he fits now will be solid-state and hence lighter and use far less power than the magnetron sets many here are used to. The radar processing software in modern plotters is also much better, reducing the need for skill and constant practice. My last Channel crossing was in thick fog with a failed AIS and a modern Quantum radar with Axiom display, and it was night and day compared to our old C-Series radar. No manual plotting - just tap on a return and then "Acquire Target" on the menu that pops up, and it gives you a continuous range, bearing, CPA etc just as with AIS. It's not quite as accurate as AIS, but plenty good enough for crossing the shipping lanes with confidence. I was quite happy to leave one of my fairly inexperienced (though very sharp) crew to work the radar for most of the crossing.
Pete
Pete
prv
Well-Known Member
True. The time we were in thick fog with a dodgy radar (actually a dodgy C-Series plotter screen, a well-known problem) we had AIS receive on a separate display but saw very few targets around us. Yet we could hear small fast motorboats whizzing past us - hopefully they were avoiding us by radar, because when ours was down we had no way of detecting them except sound (by which time they were already abeam us) and we didn't at that time have an AIS transmitter. We also heard and smelled (diesel exhaust - leave the French jokes aside!) the small French Navy warship we'd seen that morning pass very close alongside us, again with no other way to detect it because the plotter was on the blink again and she wasn't transmitting AIS.
As far as I remember, we were the only ones (except the lighthouses and buoys) sounding a foghorn, too.
Pete
Bobc
Well-Known Member
First comment:-
Don't rely on others seeing you and taking avoiding action. The most important thing is that you can see them. So on that basis I would say AIS receiver is the cheapest and most effective device as it will allow you to see all of the commercial shipping and most of the pleasure boats too. It's easy to use and understand, and if you need to ask a ship to alter course, the AIS will give you their name and DSC so you can call them up and chat to them on VHF.
Second comment:-
Radar is fine so long as a) you know what you're looking at (not very easy to read on its own), b) you have the power to run it (I would suggest that you need to be running the engine if using it for an extended period). The easiest way to read a radar display is if it is overlaid on a chartplotter. If you have AIS receive, you will see radar blobs over the AIS targets, which is quite reassuring.
AIS transmit, well I now have one but only really because people want to see where I am on my up-coming cruise. Otherwise, I rely on keeping out of the way of commercial shipping.
Don't rely on others seeing you and taking avoiding action. The most important thing is that you can see them. So on that basis I would say AIS receiver is the cheapest and most effective device as it will allow you to see all of the commercial shipping and most of the pleasure boats too. It's easy to use and understand, and if you need to ask a ship to alter course, the AIS will give you their name and DSC so you can call them up and chat to them on VHF.
Second comment:-
Radar is fine so long as a) you know what you're looking at (not very easy to read on its own), b) you have the power to run it (I would suggest that you need to be running the engine if using it for an extended period). The easiest way to read a radar display is if it is overlaid on a chartplotter. If you have AIS receive, you will see radar blobs over the AIS targets, which is quite reassuring.
AIS transmit, well I now have one but only really because people want to see where I am on my up-coming cruise. Otherwise, I rely on keeping out of the way of commercial shipping.
jbweston
Well-Known Member
I think it comes down to your budget, the conditions you intend to sail in, your attitude to risk of collision and whether you like gizmos. That's why you're getting lots of different responses.
For what it's worth I have radar, AIS transponder and radar reflector, and would add a radar transponder if I sailed often in UK waters, but in the Baltic and Skagerrak we don't get much summer fog. Or darkness for that matter . . .
For what it's worth I have radar, AIS transponder and radar reflector, and would add a radar transponder if I sailed often in UK waters, but in the Baltic and Skagerrak we don't get much summer fog. Or darkness for that matter . . .
