AIS or RADAR or Both

[mparent]

With the AIS being so popular is radar still necessary or will an AIS (receiving and transmitting) hooked to a laptop or chart plotter do the trick

[Zanshin]

Rain squalls, uncharted rocks, coastlines and vessels without AIS still have radar echoes and don't require functioning GPS. AIS with RADAR is absolutely fantastic.

[David M]

mparent,
AIS only shows boats with AIS transceivers. There is a whole lot more useful information on a radar than that.

AIS is a supplement to your existing navigation tools and not a replacement for anything.

In addition to the newer radars, you can also get PC/Mac compatible chart software that shows other vessels with AIS transceivers.

[CARL]

totaly agree with all above,i have both and when entering a harbour in thick fog on one occ ,a large ship came in behind,it looked like an island closing down on us and the radar screen became very cluttered, the ais came into its own then by indicating at a glance which way he was turning so we could do opposite and keep out of his way. One thing i might suggest is have the ais as a stand alone unit, then when in open sea you can switch off ,radar and plotter which both draw a lot of amps,the ais can be set with say a 6 mile alarm to allertyou of any large vessels in the area you still need to use your eyes but a quick scan of the horizon every now and then. thepower useage of the ais is tiny .

[S&S]

Originally Posted by Zanshin

Rain squalls, uncharted rocks, coastlines and vessels without AIS still have radar echoes and don't require functioning GPS. AIS with RADAR is absolutely fantastic.

Radar w/ mini ARPA and AIS (transceiver, NOT a receiver) are real "save-your-bacon" propositions. Having a radar die at an inopportune moment, without AIS (like what happened to us in the Manitou Passage) was not a good thing. Big boat watch crews aren't looking for small radar reflections and the first we saw of the Laker coming out of the fog it was aimed at our beam and under 100' away.No sound signals from them either. An appatite losing proposition, to say the least.

We now carry both.

[Talbot]

AIS and Radar are not an either/or kit, but are complimentary. That is they do different jobs, but each helps the other to do their tasks.

IMHO AIS is essential if you are sailing anywhere near a busy commercial shipping route.

IMHO Radar is essential if you are in fog.

[conachair]

Originally Posted by mparent

With the AIS being so popular is radar still necessary or will an AIS (receiving and transmitting) hooked to a laptop or chart plotter do the trick

Not sure about anything being 100% *necessary* on a boat apart from keeping the water out but I have both, given the choice of only one I´d go for radar without a doubt. But love the ais dearly as well. Agree with stand alone unit, I have a little nasa which does everything i need, draws little power and doesn´t rely on other bits of kit to do it´s job.

[speakeasy]

Originally Posted by David M

mparent,
AIS only shows boats with AIS transceivers. There is a whole lot more useful information on a radar than that.

AIS is a supplement to your existing navigation tools and not a replacement for anything.

In addition to the newer radars, you can also get PC/Mac compatible chart software that shows other vessels with AIS transceivers.

Agree completely with your remarks. The software you mentioned can be found live at Live Ships Map - AIS - Vessel Traffic and Positions

[capt_douglas]

With the cost of AIS receivers coming down rapidly, I recommend at least the receiver. You'll get a lot more data further off than with any form of electronics. The IMO is requiring more and more boats, of lesser tonnage, to carry AIS transceivers and those are the ones the seem to have no one at the wheel. Being able to call that freighter by name, IMO number, course, and speed can improve your chances of getting a reply. You can also use their MMSI number with your DSC VHF to send a text message.

Unfortunately, radars don't seem to be dropping in price as fast. ARPA can be integrated into the radar and may be able to output to your chart plotter. There is a mini-ARPA that tracks fewer than the required number for full blown ARPA radars at a lower price.

In my experience, AIS&ARPA on a radar clutters it up too much for me. Same for radar overlays on the chart plotter.

Then there's the power cost. AIS receivers take about an amp/hour to run so leaving it on at night, or all the time, is doable in most smaller boat situations. Radar takes some power, even if yours allows intermittent transmit. If you have smaller battery bank, charging restrictions, or weak batteries, you may not be able to run the radar as often as you want; or need to. IMO, it's as waste of money if you can't get full use out of something. Many cruisers use the radar at night to warn them of approaching "hard objects" and even in timer/intemittent sweep mode, power consumption can be considerable.

My preference order:
(1) AIS receiver
(2) radar
(3) radar with ARPA
(4) AIS transceiver
(5) AIS overlay on chart plotter

Most of the boats I work on have a separate AIS transceiver and ARPA radars. Thoughtful installation means a quick glance at the AIS display or navigation software to see what's going on.

Radar can be a real anxiety saver but it requires good target reflection to work well. Low lying atols, small boats, and low in the water obstructions can be masked by sea clutter. However, in those dark night, furious rainstorms, when getting back to the harbor is important, nothing is as good as radar. Same for the unresponsive tanker or field of fishing boats; you can test your course correction to see what'll happen on the radar before executing it.

[RikHall]

Both - they compliment each other so well.

We have had radar on the past two boats (ten summers) and AIS on the last two for five summers.

For me, at less than $200.00, the AIS receiver was a no brainer,

Rik

[highseas]

Having just sailed down the west coast with an ais receiver,the amount of boats using ais is small.None of the many fishboats we saw were transmitting,only tugs and ships.I would definitely get a transponder now that I know how well they work.I pick up targets at almost 50 miles,much better than radar.I would use it on a separate screen from plotter, for clarity.

[freetime]

Broadband Radar.....woow...

And AIS, it is a very fast and easy way to find out collision course to just see their direction and speed. Perfect for north sea...

So the best is both, the ships see you and you see them....

[TritonSailor]

I like the idea of both as well, while flying in helo's in the military, we used AIS and IFF(Identify Friend or Foe), it is still used extensively today not only to discern friendly's from the enemy but to maintain separation. Radar though not used often on the boat,comes in handy at night as a backup for navigation or transiting through fog. The great thing about an AIS "Transceiver" is that not only can you see other ships that transmit AIS, but you have made yourself a big target to them. I believe that with the density of shipping traffic increasing steadily, the AIS Transceiver should be a mandate just from a safety aspect.

Regards

Jeff