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- Thread starter Gregoryulrich
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Take a look at this study regarding the effectiveness (or not) of radar deflectors...
http://www.ussailing.org/wp-content...ore/SAS Studies/2007 Radar Reflector Test.pdf
Mark
I think I remember coming across this previously, and wasn't sure what to make of the "customer contact" shown on page 3: Capt N Beer.
Whatever the case, the recommendations all point to $300+ solutions, prompting me to think that AIS, keeping watch, and getting out of a ship's way could be more effective.
Whatever the case, the recommendations all point to $300+ solutions, prompting me to think that AIS, keeping watch, and getting out of a ship's way could be more effective.
Here's a link to the accident report that prompted the study. A sailboat was ran over at night by a ferry, killing all three crew. The ferry did not see the boat on their radar...
http://www.ziltmagazine.com/bestanden/ouzo.pdf
Mark
http://www.ziltmagazine.com/bestanden/ouzo.pdf
Mark
Gregoryulrich
Member III
A radar reflector is one thing I don't need to purchase. I have one. It's buried in the Vee berth storage somewhere. I haven't figured out how to mount it but I was leaning towards using the pennant hoist.
Thanks for forwarding. What a tragedy.
My takeaway is that the report makes a case for having at least an AIS receiver (preferably transceiver) on board, which the Ouzu did not have. The Ouzo had a 6" octahedral radar reflector on board (and a VHF), which was obviously ineffective even with an apparently attentive crew checking radar on the ferry. Relatively ineffective also were the Ouzo's nav lights. When they were finally seen by the watchman on the ferry, it was too late.
And man, that's a big ferry. I've sailed in SF Bay at night plenty, and even on clear nights, it's hard to see the ships, but that's against a backdrop of city lights. I don't know what it would be like to spot a ship on the ocean at night, but I do know that AIS (and radar) would probably help put my mind a little more at ease, and that on the list of collision-avoidance tactics, my own ability to identify and avoid oncoming ships gets the greatest priority.
Still, it gives some pause to consider this all happened on a clear August night with gusts to 6 knots.
My takeaway is that the report makes a case for having at least an AIS receiver (preferably transceiver) on board, which the Ouzu did not have. The Ouzo had a 6" octahedral radar reflector on board (and a VHF), which was obviously ineffective even with an apparently attentive crew checking radar on the ferry. Relatively ineffective also were the Ouzo's nav lights. When they were finally seen by the watchman on the ferry, it was too late.
And man, that's a big ferry. I've sailed in SF Bay at night plenty, and even on clear nights, it's hard to see the ships, but that's against a backdrop of city lights. I don't know what it would be like to spot a ship on the ocean at night, but I do know that AIS (and radar) would probably help put my mind a little more at ease, and that on the list of collision-avoidance tactics, my own ability to identify and avoid oncoming ships gets the greatest priority.
Still, it gives some pause to consider this all happened on a clear August night with gusts to 6 knots.
I've been asking that too. The report makes the point that the ship had been executing a turn just prior to the incident, before they spotted to Ouzu. The authors further speculate that this turn may have confused the two sailors on watch on the Ouzu, causing them to think that the ferry's turn could have been executed to avoid collision. If that's true, I can imagine that as they watched, perhaps paralyzed in anticipation of what would happen next, that they failed to take any other action until it was too late (cluster of lights just before the collision, etc...).
Irrespective of whatever was happening on the Ouzu, there's a lesson to be learned there too: Take action early, and in open water at night, don't be shy about establishing radio contact with an approaching vessel.
Irrespective of whatever was happening on the Ouzu, there's a lesson to be learned there too: Take action early, and in open water at night, don't be shy about establishing radio contact with an approaching vessel.
That report is thorough (one way to put it) but populated with speculation and straw dogs, and based on statements from the ferry crew which must be taken on faith. Still, what is says to me is that, as a practical matter, if we get run down it's our own fault. My guess is few ships crews are as trained and responsible as the crew of a very large passenger ferry.
Issues of night vision on the ferry? Issues of the coating on the lookout's eyeglasses? Investigation of whether the red filter was on or off? Bah. Every container ship I have seen offshore has its decks lighted like a used-car lot. They come up on the horizon at night like Venus. Five miles away they blaze with white lights that overwhelm their huge running lights. I can only assume they burn all that light because they intend to be seen, and that being seen is their last line of defense against running down small boats, night and day, which don't show well on radar.
The 25-foot sailboat had no life raft and no EPIRB. It sank. We obviously need a life raft and a (GPS) EPIRB. Without that minimum gear, available for 40 years, there is not much chance of surviving a catastrophic event.
The report talks about VHF communication and why didn't they call before or after the event. I personally put no stock in VHF, although it's a good tool.
The report talks about setting off flares or illuminating sails to alert a ship. I put no stock in that either, although I'll sure do it.
The report makes this statement (2006):
AIS is being carried by an increasing number of yachts, partly to assist in their beingmore “visible”. Had Ouzo carried AIS it would have made no difference to the outcomeas AIS information was not displayed on the radar of Pride of Bilbao.
Perhaps the sentence means that the ferry was not equipped with AIS, although that's not what it says. But it is not important whether the ferry was or was not monitoring an AIS or radar display; what is important is that a yacht is. Or, have a lookout who sees the ferry before the ferry sees him.
The thread is about running lights. Yes, it's important to have running lights to avoid catastrophic collisions.
But in the end, not very important.
Survival lies elsewhere.
Issues of night vision on the ferry? Issues of the coating on the lookout's eyeglasses? Investigation of whether the red filter was on or off? Bah. Every container ship I have seen offshore has its decks lighted like a used-car lot. They come up on the horizon at night like Venus. Five miles away they blaze with white lights that overwhelm their huge running lights. I can only assume they burn all that light because they intend to be seen, and that being seen is their last line of defense against running down small boats, night and day, which don't show well on radar.
The 25-foot sailboat had no life raft and no EPIRB. It sank. We obviously need a life raft and a (GPS) EPIRB. Without that minimum gear, available for 40 years, there is not much chance of surviving a catastrophic event.
The report talks about VHF communication and why didn't they call before or after the event. I personally put no stock in VHF, although it's a good tool.
The report talks about setting off flares or illuminating sails to alert a ship. I put no stock in that either, although I'll sure do it.
The report makes this statement (2006):
AIS is being carried by an increasing number of yachts, partly to assist in their beingmore “visible”. Had Ouzo carried AIS it would have made no difference to the outcomeas AIS information was not displayed on the radar of Pride of Bilbao.
Perhaps the sentence means that the ferry was not equipped with AIS, although that's not what it says. But it is not important whether the ferry was or was not monitoring an AIS or radar display; what is important is that a yacht is. Or, have a lookout who sees the ferry before the ferry sees him.
The thread is about running lights. Yes, it's important to have running lights to avoid catastrophic collisions.
But in the end, not very important.
Survival lies elsewhere.
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Rick R.
Contributing Partner
One view of your HI video and the AIS alarms you showed should be enough to convince anyone, that at a minimum, an AIS receiver is a great tool. We may not be seen, but we will see them.
Grizz
Grizz
Lake Freighters
Guess it's time to weigh in from the middle of the continent...
Lake Michigan shipping lanes are well marked on the charts, including ferry routes. One, The Badger, is still a coal burning ferry, last of its kind on the lake. Lake freighters are a special breed, 750'-1000' in length and are usually well lit stem to stern. This makes identifying specific port/starboard running lights a bit tricky, especially as they have intermediate lights. Darkness + fog is the greatest danger and also when an AIS receiver would be welcome, and when a transceiver would be golden.
Our boats don't show much of a profile w/o a radar reflector and some of the reflectors do lose their effectiveness when subjected to rolling/pitching conditions, which happens often in Lake Michigan's 'square wave' conditions (7' on the lake creates short periods & steep walls = 'beat to heck').
To illustrate the lack of profile, it was pitch black mid-July a few years ago, 1 AM, no moon and 2 of us were on watch having just exited The Manitou's, motoring in no-wind conditions on a SW heading. We had spotted a freighter to our stern @ 4 miles on what appeared to be a similar heading. We thought it was just the 2 of us on the lake. Our VHF lit up, the freighter calling "sailboat, sailboat, please announce your intentions". Both of us were suddenly very awake.
The freighter repeated the message shortly after the 1st. We responded, thinking he was hailing us, and we informed the freighter that we were on a SW heading 4 miles ahead and would alter to a southerly course, opening an unobstructed path.
That's when a 3rd voice was heard, with a message something like "Yeah, I see ya, I'll sail cross your course, no worries. I'm headed in". Wow. We couldn't see those running lights, even with the long-eyes that came out immediately. We had no AIS (but wished we had) and the freighter made no response to the nonchalant reply. The radio was silent the rest of the night, so we assumed there was no incident.
It took a while for the adrenaline to work its way through our systems. We definitely had something to relay at shift change when the question was asked "anything happening that we need to know about?"
There's now an AIS receiver on board and it has helped a few times, if only to swing a wide berth for the big boys on the lake...
Guess it's time to weigh in from the middle of the continent...
Lake Michigan shipping lanes are well marked on the charts, including ferry routes. One, The Badger, is still a coal burning ferry, last of its kind on the lake. Lake freighters are a special breed, 750'-1000' in length and are usually well lit stem to stern. This makes identifying specific port/starboard running lights a bit tricky, especially as they have intermediate lights. Darkness + fog is the greatest danger and also when an AIS receiver would be welcome, and when a transceiver would be golden.
Our boats don't show much of a profile w/o a radar reflector and some of the reflectors do lose their effectiveness when subjected to rolling/pitching conditions, which happens often in Lake Michigan's 'square wave' conditions (7' on the lake creates short periods & steep walls = 'beat to heck').
To illustrate the lack of profile, it was pitch black mid-July a few years ago, 1 AM, no moon and 2 of us were on watch having just exited The Manitou's, motoring in no-wind conditions on a SW heading. We had spotted a freighter to our stern @ 4 miles on what appeared to be a similar heading. We thought it was just the 2 of us on the lake. Our VHF lit up, the freighter calling "sailboat, sailboat, please announce your intentions". Both of us were suddenly very awake.
The freighter repeated the message shortly after the 1st. We responded, thinking he was hailing us, and we informed the freighter that we were on a SW heading 4 miles ahead and would alter to a southerly course, opening an unobstructed path.
That's when a 3rd voice was heard, with a message something like "Yeah, I see ya, I'll sail cross your course, no worries. I'm headed in". Wow. We couldn't see those running lights, even with the long-eyes that came out immediately. We had no AIS (but wished we had) and the freighter made no response to the nonchalant reply. The radio was silent the rest of the night, so we assumed there was no incident.
It took a while for the adrenaline to work its way through our systems. We definitely had something to relay at shift change when the question was asked "anything happening that we need to know about?"
There's now an AIS receiver on board and it has helped a few times, if only to swing a wide berth for the big boys on the lake...
Seeing and Being Seen
Our plan is to add AIS for this season. I know it's a good tool, and then it's also time to upgrade to a current-technology vhf anyway.
About those radar reflectors. I have read the tests over the years and some of them seem to do a better job than the others, but my take-away is that you first need some sort of reflector, regardless of shape or sophistication.
My anecdotal evidence is an incident many years ago when we were motoring down the river in our just-purchased boat with its original Apelco first-generation green screen radar. A friend was motoring along about a thousand yards away. I tried to adjust the radar to see his boat and it seemed like no matter how I adjusted the sensitivity/gain he just was not showing up on that screen.
So I called him on the vhf and asked if he had a reflector on board. He did, and brought it up on the cockpit seat from down in the cabin... immediately his boat showed up as a strong return!
That reinforced the idea that frp boats with oval aluminum masts return very little signal.
Nowadays we have a tubular reflector on a shroud above a lower spreader.
Our experience, FWIW.
Loren
Our plan is to add AIS for this season. I know it's a good tool, and then it's also time to upgrade to a current-technology vhf anyway.
About those radar reflectors. I have read the tests over the years and some of them seem to do a better job than the others, but my take-away is that you first need some sort of reflector, regardless of shape or sophistication.
My anecdotal evidence is an incident many years ago when we were motoring down the river in our just-purchased boat with its original Apelco first-generation green screen radar. A friend was motoring along about a thousand yards away. I tried to adjust the radar to see his boat and it seemed like no matter how I adjusted the sensitivity/gain he just was not showing up on that screen.
So I called him on the vhf and asked if he had a reflector on board. He did, and brought it up on the cockpit seat from down in the cabin... immediately his boat showed up as a strong return!
That reinforced the idea that frp boats with oval aluminum masts return very little signal.
Nowadays we have a tubular reflector on a shroud above a lower spreader.
Our experience, FWIW.
Loren
Gregoryulrich
Member III
Your anecdote makes a powerful case Loren, thanks for sharing that.
AIS in your hand.
Fellas, We don't have an AIS feature on our ICOM receiver but do have two apps on our iPhones that do pretty much the same. I have Ship Finder on mine and Marilyn has another on hers. I've compared the two and prefer mine, she's compared the two and prefers hers. A mere $5.00 gets anyone a pretty powerful AIS at their fingertips. I haven't been following this thread word for word, I just hope I'm not repeating something already said. Cheers, Glyn Judson, E31 hull #55, Marina del Rey CA
Fellas, We don't have an AIS feature on our ICOM receiver but do have two apps on our iPhones that do pretty much the same. I have Ship Finder on mine and Marilyn has another on hers. I've compared the two and prefer mine, she's compared the two and prefers hers. A mere $5.00 gets anyone a pretty powerful AIS at their fingertips. I haven't been following this thread word for word, I just hope I'm not repeating something already said. Cheers, Glyn Judson, E31 hull #55, Marina del Rey CA
Gregoryulrich
Member III
How useful would you say an AIS transceiver is with its ability to transmit AIS information?
I use an AIS app called Boat Beacon on my iPhone. Though, you do need cell coverage for these apps to work. Last year, I was helping a friend move his Yankee 30 overnight 90 miles from Portland to Astoria, down the columbia river. The AIS app was very helpful in knowing where the large container ships and barges were. We were even able to transmit our own position through the app, and a large ship hailed us by name to let us know where he was headed, and that he'd also let other ships know where we were headed.b last month, I also upgraded my vhf to one with AIS/DSC/GPS.
Mark
Mark
Rick R.
Contributing Partner
Nav lights, AIS, visibility and more.....
I started with the AIS app on my iPhone and iPad and it works pretty well. You have to be within cell range for it to work though. Last summer we were traveling in a heavy rain storm in the ICW with visibility down to 1/10 mile. We were in a very narrow section (about as wide as a small river) and well within cell range. My AIS app did not pick up a large tug with a double barge approaching my bow. He was about 1/4 mile away. When I hailed the Capt. on VHF and said he wasn't showing up on my AIS, he told me that the apps "have holes in their coverage" and should not be trusted. He then asked me if I knew there was another ship approaching from my stern. Didn't see him either!
I installed a Standard Horizon VHF with built-in AIS receiver that displays vessels on my Garmin 740s plotter. Not as good as an AIS transceiver but I have more confidence than before.
Glyn, I still have the apps and use them from home to see who is out. Marine Traffic is a wonderful app and is free.
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Maybe we should rename this thread "SEE AND BE SEEN." I agree that the cell phone AIS apps should only be used as another tool, and not solely relied upon. Traveling down the Columbia river that cold, rainy, and foggy night made me a true believer in radar, which we relied on more than AIS. Not only could we pick up approaching ships on radar before visual contact, we could also see the navigational aids and other hazards on the radar before we could see them with our eyes.
I can't see AIS targets very well on my cockpit 5" GPS screen. I have to zoom in and out, and conditions--night, day, rain, fogged reading glasses--complicate everything.
The Vesper installed at the nav station below offers a radar-screen -like depiction that is always clear. It uses a splitter connected to the masthead VHF antenna. The installation adds up to about $1,000.
Offshore last summer, most ships showed up at 7 NM, some not until 3 NM. All eventually showed up, with course, speed, distance and Point of Closest Approach (the magical datum).
I installed a $5 buzzer that went off when any ship came within three miles. It is like a shot of adrenalin to the heart. I encountered about two dozen ships Hawaii and back, most in shipping lanes.
Only one in five ships transmitted the additional info of destination, cargo, and so on. None tried to contact me. I had the potential to direct-dial their MM number at any time.
A dedicated AIS display is mighty fine.
The Vesper installed at the nav station below offers a radar-screen -like depiction that is always clear. It uses a splitter connected to the masthead VHF antenna. The installation adds up to about $1,000.
Offshore last summer, most ships showed up at 7 NM, some not until 3 NM. All eventually showed up, with course, speed, distance and Point of Closest Approach (the magical datum).
I installed a $5 buzzer that went off when any ship came within three miles. It is like a shot of adrenalin to the heart. I encountered about two dozen ships Hawaii and back, most in shipping lanes.
Only one in five ships transmitted the additional info of destination, cargo, and so on. None tried to contact me. I had the potential to direct-dial their MM number at any time.
A dedicated AIS display is mighty fine.