Some sailors say… with AIS vs Radar, radar’s not necessary if you’ve got AIS
Others won’t leave the dock without radar.
Me? I think with AIS vs Radar, they both rock… and they don’t replace each other.
Radar shows distance, speed, course, and heading… AIS gives you that info too…
But only if the target has AIS installed and turned on.
AIS also shows the vessel’s name and type… useful when you need to hail them and suggest they not mow you down.
AIS broadcasts your position, so anyone tracking you on MarineTraffic.com or Vesseltracker.com knows exactly where you are from your last update.
That’s sometimes handy and sometimes creepy.
Radar overlay on your chart plotter is outstanding… feels like sorcery.
If forced to choose AIS vs Radar
But if you’ve got both and someone makes you choose between AIS vs Radar, like in a nautical version of “Would You Rather”?
Keep radar.
Here’s why.
You can spot targets on radar that AIS completely misses, especially in fog when visibility drops to zero. Like dodging icebergs… no AIS, obviously.
But there’re Crab pots and long-line buoys?
They barely show up on radar. Tuning the gain might help.
Bottom line?
Radar and AIS are tools… like GPS.
They both help… if you turn them on and know what you’re doing.
AIS vs Radar Display
Headed offshore and AIS is down?
Still going? Hell yes, if there are looming big problems like flirting with hurricane season.
Radar down?
I’d hesitate particularly if I’m heading into an area of high fishing or hazards.
AIS v Radar – which has the best features?
AIS is great for vessel ID… name, size, type.
Offshore, calling a mega-ship by name changes everything.
Confirms whether someone’s awake… or you have to take action
But radar?
Radar doesn’t wait for cooperation.
It powers up and hunts.
Targets ships, rocks, land, squalls… anything it can detect.
I wouldn’t head offshore without it.
It can guide your route, your anchor drop, your entire strategy.
AIS pulls weight… but don’t trust it for collision avoidance because not everyone runs with it.
Some turn it off… for privacy, ego, or pirate cosplay.
Like a 150-foot superyacht bristling with gear… but no AIS signal.
And sometimes? AIS lies.
It only shows what someone else’s gear says… if it shows anything at all.
Doesn’t alert you to reefs or squalls.
If I had to pitch one overboard?
AIS hits the drink.
Until most boats get serious about it, radar stays king… especially in crowded zones.
People forget:
Radar shows what’s actually out there.
AIS shows what someone says is out there… and that someone might be wrong or silent.
However, using Radar takes skill. It’s not magic.
And if you want others to see you? Get a good radar reflector.
In fog? You might wish you’d taken the plunge when the visibility closes in even though Radar is more expensive than AIS.
Near a swarm of fishing boats?
Radar leads and is good for tracking squalls.
Radar shines when charts look sketchy… or you’re debating where to drop anchor.
But AIS is still great if you’re wondering if that big ship sees me… if that 800-foot missile barrelling towards you at 16 knots even noticed you.
Fair or not, AIS plays a big role in collision avoidance on big ships.
I want to be the blinking dot they can’t ignore.
Sure, they’ve got radar… but AIS confirms I exist and commercial crews check the AIS screen.
Freighters don’t watch for flapping canvas.
If something goes sideways?
AIS data decides who gets fined, fired, or flamed.
And AIS lets them call me by name… or vice versa.
Screaming “white sailboat!” into the void is not going to cut it these days… that’s over.
Now they answer… well, hopefully
And that lowers the blood pressure during shipping-lane roulette.
A neat function is AIS linking to VHF.
See a ship. Press a button.
Boom… your radio dials their MMSI direct.
No scribbles. No errors.
System works. Clean.
And just because a ship is big doesn’t mean it’s packed with crew.
A lot run skeleton teams.
One person on the bridge… juggling technology and caffeine… or maybe halfway into the head.
That’s the game… lean crewing saves cash… but it spikes the risk.
That’s why DSC matters. DSC refers to Digital Selective Calling, a feature on VHF marine radios that enables digital communication for distress calls, individual vessel calls, and group calls.
But to use DSC… you need their MMSI.
AIS hands that to you on a silver platter.
If your call goes unanswered… the odds are no one’s at the wheel.
It kinda matters when a container ship is aimed straight at your soul.
Bottom line is with AIS vs Radar…
AIS doesn’t replace Radar.
Radar doesn’t replace AIS.
Neither replaces VHF or DSC.
Use them all.
So AIS vs Radar? They both work solidly and best not leave the dock without them.
And yeah… I still use my eyes, too.
Dream… Explore… Discover…
James Miller
