Radar or Not ?

[FlyingCloud1937]

Originally Posted by s/v Jedi

How can you plot charts when you don't have the charts? I hope this isn't the old "must be paper charts or you die" argument again....

I agree that AIS is not a must-have tool yet but it's close and only a matter of time before it will be. Apparently it already is needed in India if you want to see channel markers.

ciao!
Nick.

I have 2 different GSP receivers and 2 chart plotters on-board, as well as 2 separate depth sounders, and a radar, and 2 vhf w/registered DCS, and a CB, and a AIS. I also have a laptop, all systems are nema networked.

I have three horns mounted, with 1 air compressor, with a co2 bottle plumbed in for back-up, plus I have a case of hand held horns

I also have a full set of paper charts, as well as duplicate chart chips. I also have the paper charts open, and I always plot on paper when running in fog, at night, or when operating in unfamiliar water.

I always review the paper as well as the chart-plotter and radar when entering a new harbor, as well as all harbors I enter on an irregular basis. I update both paper and electronic charts.

I take it all as part of my responsibility. To those on-board my boat, and those who I cross paths with on the water.

Lloyd

[DotDun]

Originally Posted by DotDun

In fact, I'll go as far to state that AIS receivers for boats should have never been built!

If you don't deploy an AIS transceiver, what's the point? The AIS system is predicated on boats transmitting data, if you only receive, no other AIS can see you! Collision avoidance is a multi-player game.

Originally Posted by conachair

Sorry to disagree but in IMHO that statement is completely absolutely nuts. Do what you will, I think pretty much anyone loaned a a reciever for a month would really not want to give it back after the month was up.

Now we're getting to the real attraction to AIS! It's people loving the fact they can tell the name, heading, speed, etc. of the big vessel they see on the horizon or the ones moored in port. None of which aid navigation until the information is used in the context of collision avoidance.

Originally Posted by conachair

Ais and radar are 2 different things, why confuse the 2? Thats where the arguments come start.

I agree AIS and radar are different animals. And I like AIS, but until every vessel deploys a transceiver, AIS should never be the primary tool for collision avoidance! I not confused about it, but some are.

Originally Posted by conachair

As for radar, it's great. Mine is used mostly for the alarm offshore solo. Apart from that still love it dearly. It earned it's keep just once round the Atlantic in fog down the portuguese coast. For the other 5 years minus 1 day I could easily have lived without it, but would rather not. It's great but not having it won't automatically mean you die.

You were not in collision avoidance mode except for 1 day of the last 5 years. But, when you were performing collision avoidance, you used your radar. I believe we agree.

[goboatingnow]

Originally Posted by FlyingCloud1937

David,

I can see you're any easy one to get into arguments with. I won't play your game of Ridicule/belittlement.

So if you read my post without a preconceived position, then you will understand what I wrote.

AIS is a luxury, I stand behind that statement. If you follow my top ten list you can safely navigate without an AIS. As a matter of fact there are more people navigating without AIS then with.

Sure AIS can aid navigation but it is not required. Anyone navigating in fog with with and AIS instead of radar is a life threat to everyone on their vessel, as well as every other vessel in the vicenity.

Anyone navigating with a chart plotter, minus charts is a threat to themselves, and those on-board.

How can you argue any point.

Lloyd

Youre a howl Lloyd.

om your calculations theres an awful lot of " threats to themselves" our there

So all boats in fog without radar are threats to themselves,well I dont know how we managed before small boat radar,,,,,#

AIS is not a subsitute, but in my book if money is tight Id fit an AIS transponder first, then a radar. If I could afford it, I'd fit both.

Dave

[Bash]

AIS is a dependent option. Those using it for collision avoidance are depending on other boats (1) having a transmitter, (2) turning it on, (3) maintaining it in working condition. With radar, I'm not dependent upon another boat's equipment. If mine works, I get the picture.

[Astrid]

Yes, it is a matter of passive (AIS) collision avoidance versus active (radar).

[FlyingCloud1937]

Originally Posted by goboatingnow

Youre a howl Lloyd.

om your calculations theres an awful lot of " threats to themselves" our there

So all boats in fog without radar are threats to themselves,well I dont know how we managed before small boat radar,,,,,#

AIS is not a subsitute, but in my book if money is tight Id fit an AIS transponder first, then a radar. If I could afford it, I'd fit both.

Dave

Your the one howling.

From your signature "logic" - A way of going wrong with confidence

As master of the ship, you and only you are responsible for everyone on-board. If someone hits you in fog, they may be the cause of the accident, but if you would have radar, then you would in most cases be able to avoid the accident, and you would truly be master of your ship.

Without radar you are the master of the disaster. It will be a long painful balance of life, knowing that you alone were responsible for the loss of life on-board your vessel. Radar can avoid a grounding ans subsequent sinking, as well as many other features that a AIS could never be a player in.

A proper radar can show everything that an AIS can show, everything that is imporant.

Lloyd

[FlyingCloud1937]

Originally Posted by David_Old_Jersey

You could hire someone to follow you around in a RIB - is your life not worth that expense?



Not really sure where that linkage comes from



ROTFLMAO You must be a marketeers wet dream

Point





http://www.cruisersforum.com/forums/...fog-57840.html

Originally Posted by David_Old_Jersey

"A French fisherman onboard a boat that was hit by the Condor Vitesse this morning has died" (no pics of the French boat - but from description sounds like around 10 metre / 30 foot commercial fishing boat. in that location probably a Potter).

"The ferry was en route from France when it struck a vessel at around 7.45am, 45 minutes into the journey" (it's about a 40 mile crossing - usual journey time around 1 hour 15 mins).




"It was in French waters, east of the Minquiers" (just over half way into the Journey....bang on schedule - at service speed of 38 knots).

"Channel 103 spoke to passenger Marilyn Tomes onboard the Vitesse shortly after the accident happened. She described a 'sudden jolt'. Then she saw a plank of wood passing by the window". (given the height of the windows that plank didn't float past. and "sudden jolt" on something that size wouldn't be 5 knots)

"Describing the conditions at sea, Marilyn said the water was calm but it was 'very foggy'. " (From the passenger videos on TV, fooking foggy would be more apt. I'd have been worried about hitting something on a sailboat).


Jersey Insight - Your local Jersey directory, news, weather and classifieds

Fisherman dies after Channel collision - Fishupdate.com


Service speed of 38 knots - given the location of the incident, seems pretty clear that they were relying on radar and in an area known to be used by commercial fishermen as well as other vessels (not a formal shipping lane - just the route to France / Jersey).



HSC Condor Vitesse - Wikipedia, the free encyclopedia

From my own experiance of these vessels (onboard) and from sea level - they do seem to expect others to clear a path. Which given there size and speed (and inability to stop) folks do.......but to my mind 38 knots in thick fog is just homicidal

IMO really just an incident waiting to happen. All very sad for those concerned, but a bit of a conundrum for other boat users..........

Counter Point

Originally Posted by FlyingCloud1937

Your the one howling.

As master of the ship, you and only you are responsible for everyone on-board. If someone hits you in fog, they may be the cause of the accident, but if you would have radar, then you would in most cases be able to avoid the accident, and you would truly be master of your ship.

Without radar you are the master of the disaster. It will be a long painful balance of life, knowing that you alone were responsible for the loss of life on-board your vessel. Radar can avoid a grounding ans subsequent sinking, as well as many other features that a AIS could never be a player in.

A proper radar can show everything that an AIS can show, everything that is imporant.

Lloyd

What's your point??????????????

[conachair]

Originally Posted by DotDun

Now we're getting to the real attraction to AIS! It's people loving the fact they can tell the name, heading, speed, etc. of the big vessel they see on the horizon or the ones moored in port. None of which aid navigation until the information is used in the context of collision avoidance.

Yes, that's a great attraction of AIS. I can see in less than a second if the ferry doing 40Kts on the horizon is going to come anywhere close to me or if I can ignore it. My collision avoidance starts as soon as I see a big boat!

This is why during the day not in fog my radar never gets used. I find heading and speed of smaller vessils is not as much use as the fishing boats are completely irratic and yachts are possibly skippered by idiots and may well also behave in an irratic manner

You were not in collision avoidance mode except for 1 day of the last 5 years. But, when you were performing collision avoidance, you used your radar. I believe we agree.

I think we do agree, though that's not strictly true. Most of the miles were offshore where IME the very few ships I came across were always trasmitting, the radar never picked up anything which wasn't transmitting. Actually, there was one coaster, between Senegal and Cape verde but down there I kind of thought that might be the case.

It's also very satisfying on ais to watch a huge tanker change course to give me more room then change back again when clear.

The radar did actually do much more than 1 day in fog, the watch mode alarm was used anytime I was asleep. It's great, picks up squalls as well. The AIS is great as well, if something is there you can see in an instant if it's a problem or not, radar can't do this. Not mine anyway. Not in an instant.

Get BOTH!! They're both great bits of kit. Different, but great.

[goboatingnow]

Originally Posted by FlyingCloud1937

Your the one howling.

As master of the ship, you and only you are responsible for everyone on-board. If someone hits you in fog, they may be the cause of the accident, but if you would have radar, then you would in most cases be able to avoid the accident, and you would truly be master of your ship.

Without radar you are the master of the disaster. It will be a long painful balance of life, knowing that you alone were responsible for the loss of life on-board your vessel. Radar can avoid a grounding ans subsequent sinking, as well as many other features that a AIS could never be a player in.

A proper radar can show everything that an AIS can show, everything that is imporant.

Lloyd

The fact is Lloyd that small boat radar and we are talking about the typical system on board small leisure vessels does not show " everything that is important " take for example a fairly extreme crossing , the English channel in reduced visibility.

Firstly there's so much side lobe interference that separating close in vessels can be hard. Secondly vessel aspect and pulse length can produce very inaccurate indications of relative size.

Also small boat Radar with it's relative high beam spread generally struggles to display small non ferrous targets like other yachts. add in an aggressive seaway and rain and the usefullness of the tool degenerates.

Then overlay the virtual uselessness of small boat ARPA.

This means that yes radar is useful. But it's not the all powerful tool you seem to think it is.

Take AIS transceivers. Firstly you get a definitive picture of all large vessels ie everything over 300 tons, all passenger vessels etc. Increasingly you are getting other non compulsory fit vessels showing up. Then you get definitive vessel speed, true direction, rotation and importantly MMSI and name

as an aside these days in my experience no vessels reply to the " vessel
at xx yy. " call on VHF especially in crowded waters. All these vessels use AIS to hail each other by name.

now you have a picture of at least the large ( and hence fast) vessels around you. If of course you have radar you will supplement that picture with the radar information. But both system can lie so you always keep that in the back of your mind.

Now with AIS transceivers, you have something that no radar can do. It's make YOU visible to AIS equipped ships. Again my experience is that few if any ships can see grp yachts on their radar, especially in a seaway. This has been virtually always the case when I talk to ships and ask if they have me on radar.

The fact that shipping see you on AIS is a huge advantage. They will change course often miles away to open up CPAs. They will radio you to explain their intentions etc. It provides a huge piece of mind.

Radar has many advantages outside collision detection ( which actually small boat radar isn't good at anyway ) it backups up chart information, provides position fixes, it's a navigational tool. Squall detection ( though very unreliable ) RACON activation., etc

But good ones are very expensive and the cheap stuff is crap.

AIS is not a substitute for radar, no one is arguing that. It's different. But fitting AIS will soon be similar to a decision to fit a modern Depth sounder or small VHF. There's an awful lot of boats with depth sounders that can't afford radar.

This thread really is debating angels on a pin. If you are strapped for cash, then fit AIS. ( a transceiver) It's indispensable for the price ( just like depth sounders ) if you are able to afford more get a good radar.

Dave

[psneeld]

Originally Posted by goboatingnow

The fact is Lloyd that small boat radar and we are talking about the typical system on board small leisure vessels does not show " everything that is important " take for example a fairly extreme crossing , the English channel in reduced visibility.

Firstly there's so much side lobe interference that separating close in vessels can be hard. Secondly vessel aspect and pulse length can produce very inaccurate indications of relative size.

Also small boat Radar with it's relative high beam spread generally struggles to display small non ferrous targets like other yachts. add in an aggressive seaway and rain and the usefullness of the tool degenerates.

Then overlay the virtual uselessness of small boat ARPA.

This means that yes radar is useful. But it's not the all powerful tool you seem to think it is.

Take AIS transceivers. Firstly you get a definitive picture of all large vessels ie everything over 300 tons, all passenger vessels etc. Increasingly you are getting other non compulsory fit vessels showing up. Then you get definitive vessel speed, true direction, rotation and importantly MMSI and name

as an aside these days in my experience no vessels reply to the " vessel
at xx yy. " call on VHF especially in crowded waters. All these vessels use AIS to hail each other by name.

now you have a picture of at least the large ( and hence fast) vessels around you. If of course you have radar you will supplement that picture with the radar information. But both system can lie so you always keep that in the back of your mind.

Now with AIS transceivers, you have something that no radar can do. It's make YOU visible to AIS equipped ships. Again my experience is that few if any ships can see grp yachts on their radar, especially in a seaway. This has been virtually always the case when I talk to ships and ask if they have me on radar.

The fact that shipping see you on AIS is a huge advantage. They will change course often miles away to open up CPAs. They will radio you to explain their intentions etc. It provides a huge piece of mind.

Radar has many advantages outside collision detection ( which actually small boat radar isn't good at anyway ) it backups up chart information, provides position fixes, it's a navigational tool. Squall detection ( though very unreliable ) RACON activation., etc

But good ones are very expensive and the cheap stuff is crap.

AIS is not a substitute for radar, no one is arguing that. It's different. But fitting AIS will soon be similar to a decision to fit a modern Depth sounder or small VHF. There's an awful lot of boats with depth sounders that can't afford radar.

This thread really is debating angels on a pin. If you are strapped for cash, then fit AIS. ( a transceiver) It's indispensable for the price ( just like depth sounders ) if you are able to afford more get a good radar.

Dave

You keep saying small boat radar has issues or isn't good at something...well not in my experience...and as a delivery catain and everyday commercial operator I've run hundreds of boats and as many diffrent radars with little or few of the issues you are talking about.

Yes heavy thunderstoms will make it hard (maybe impossible) to use when looking for smaller targets...and so will a seaway (broadband may be resolving that) but as far as ARPA NOT working in a seaway so big deal...who needs ARPA anyway?

If the radars can pick up seagulls flying by ...the radar is capable if tweaked correctly...maybe not in all conditions...but in the vast majority of the conditions pleasure boaters cruise in.

[DotDun]

Originally Posted by conachair

Yes, that's a great attraction of AIS. I can see in less than a second if the ferry doing 40Kts on the horizon is going to come anywhere close to me or if I can ignore it. My collision avoidance starts as soon as I see a big boat!

I understand. So, just one more question. Why aren't you giving your information to the ferry doing 40Kts so he can have the same advantage in avoiding a collision with you? (i.e. an AIS transceiver)

[goboatingnow]

I dont know what radars you are using but I regularly sail in conventional grp production yachts through the busiest seas in the world

I'm just back from using a boat with Raymarine radar and recently delivered one with a standard Garmin unit.

These radars typically have beam widths of between 5 and 7 degrees. No such radar is going to detect seagulls. Even my own HD unit with 3 degree resolution struggles.

Secondly with large VLCCs around and close in there is significant side lobe interference. Add in a big seaway and I stand utterly by my assertions. Proper ARPA is very useful ( and you'll see why on any bridge of a modern ship). Yet on small boats its useless yet people who don't know any better use it and confuse themselves.

For me in determining collisions working out true direction and speed of my target is the key. AIS considerably enhances that

Dave

[conachair]

Originally Posted by DotDun

I understand. So, just one more question. Why aren't you giving your information to the ferry doing 40Kts so he can have the same advantage in avoiding a collision with you? (i.e. an AIS transceiver)

Power and cost. I have a nasa standalone which I know works down to under 11v and only draws 0.1a. Between that and an LED masthead I know I can still see and be seen, to an extent, even if the batteries die on me offshore.

And I have a steel boat, all the ships I've called up offshore had been watching me for a while & knew I was there.


There seems to be a bit of confusion over AIS class B monitoring onboard large vessils, I get the impression that radar will be monitored but not sure there is a legal requirement to monitor class B AIS. Perhaps someone here with experience onboard commercial vessils could shed a bit more light.

[barnakiel]

BTW I wonder what percentage of cruising radar owners know how to properly tune their units in various conditions. I also wonder how many of sailing boat installed units have arpa and, when not, how many radar owners would pass the test making radar plots (timed - the ship is making 20 Knots and coming your way).

I said 'I wonder' but indeed I mean 'many can't'.

Then, how efficient is a small radome, wide beam radar as a collision avoidance device?

So, to stay within the thread, I will say have radar is so dictated by your needs AND LEARN HOW TO USE IT. Understand the limitations, too.

Cheers,
b.

[psneeld]

Originally Posted by goboatingnow

I dont know what radars you are using but I regularly sail in conventional grp production yachts through the busiest seas in the world

I'm just back from using a boat with Raymarine radar and recently delivered one with a standard Garmin unit.

These radars typically have beam widths of between 5 and 7 degrees. No such radar is going to detect seagulls. Even my own HD unit with 3 degree resolution struggles.

Secondly with large VLCCs around and close in there is significant side lobe interference. Add in a big seaway and I stand utterly by my assertions. Proper ARPA is very useful ( and you'll see why on any bridge of a modern ship). Yet on small boats its useless yet people who don't know any better use it and confuse themselves.

For me in determining collisions working out true direction and speed of my target is the key. AIS considerably enhances that

Dave

First of all...the little 2kw Pathfinder Ramarines of yesteryear (since 2000) pick up birds all the time..please come over...I'll show you...

Second...I know ARPA on good systems is a worthwhile tool...but I guess after a long time using radars...it only take me a bit to figure out a collision course and only a bit more to dertermine aproximate course and speed of ther vessels...WHO CARES ABOUT ACTUAL COURSE AND SPEED UNLESS I'M THE GUNNERY OFFICER...all I need to do is avoid a collision. Higher relative speeds only makes it easier and quicker to determine the others approx course/speed and if collision exists.

Third...I operate regularly in the Delaware River which is full of large ships including VLCCs...NEVER had any interference from them that would have reduced my ability to safely navigate the river...even where it necks down to a mile or so across.

I'm not against AIS...but your assertions against small radar with my experience are just not accurate.. and to be honest...in the hundreds of threads and thousands of hours on the water with other captains...I have never heard any of your complaits at the level you suggest other than ARPA without gyro being a semi useless feature.

If you could please direct me to the wealth of info supporting your side...I would enjoy the reading.