ParaHandy
Active member
Once when entering Cherbourg in less than 50m visibility, there was a container ship parked a cable from the western entrance. His foghorn obscured the Cherbourg horn and he was holding station in a west going tide by running his engines astern whilst pointing west. I have never been so scared in my life before as I passed within less than a cable of her bows. If somebody had said of my boat ‘nice boat’ I’d have tossed him the keys and took the ferry. There are some nutters out there and the unease I felt then, grew as I read the most recent MAIB report.
In the very unlikely event that anybody will act to curtail the speed of commercial vessels in reduced visibility one wonders what tactics should be adopted to avoid a collision and whether the Collision Regulations are relevant in such situations. The fundamental problem is the disparity in speed. Where this is great, the yacht comes closer to the track of the faster vessel and this restricts the room for manoeuvre of either vessel and the angle of approach of the faster vessel becomes more acute and thus any errors in calculation of the track of the faster vessel tend to be magnified.
My premise is, almost, entirely mathematical and gleaned from boating on the Serpentine in London, you might say. But it did frighten me. However well planned a passage, fog is inevitable but what makes it toxic is the presence of very fast merchant ships who are completely disregarding the Collision Regulations.
For a yacht travelling at 5kn on a collision course forward of the beam with a container ship doing 27kn, contact at 6nm range by radar will be made when the yacht is 1nm away from collision, such is the impact of the speed disparity. The yacht skipper in these circumstances has two options: either switch the radar off and hope the container ship skipper is awake, hasn’t been on the bridge for the last 24 hrs, isn’t shorthanded, is in control, sober and not from some part of the world where human life is cheap, or, assume none of the above applies. There is a case for hitting the off button. The probability of a collision is statistically small but there are circumstances which decrease the odds eg passing close ahead of a container ship doing 27kn which most would instinctively try to avoid and in so doing and by using radar create a radar assisted collision.
My first premise is that if you, the yacht skipper, take more than 5 minutes from first seeing the target to determine and execute your collision avoidance strategy you are heading for trouble. In 7 minutes you are 4 cables away from a collision. There are significant system and human errors which can be dangerously misleading the closer you get.
My second premise is that a stabilized display which at the very least shows a North Up or stabilized EBL is essential. Calculating track, speed, CPA is all but impossible within the time you have available without such help. However, such aids are not of much benefit if you are not skilled in their use. A practical and well honed method of translating observed data into meaningful data upon which you can base your decisions is essential. In this regard, the practice of positioning the radar display in front of the helm is one that I question. Is the helm able to accomplish all that is required?
My third premise is never slow down. The faster you can go, the more room you give yourself. Substitute ‘radar’ for ‘foghorn’ in rule 19e for when reducing speed might be appropriate.
My fourth premise is never reduce the radar range to, say, 3nm. You merely make yourself blind to the one behind it and time is utterly of the essence. If there was only one rogue vessel intent on manslaughter then I could see the point, but there aren’t.
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In the very unlikely event that anybody will act to curtail the speed of commercial vessels in reduced visibility one wonders what tactics should be adopted to avoid a collision and whether the Collision Regulations are relevant in such situations. The fundamental problem is the disparity in speed. Where this is great, the yacht comes closer to the track of the faster vessel and this restricts the room for manoeuvre of either vessel and the angle of approach of the faster vessel becomes more acute and thus any errors in calculation of the track of the faster vessel tend to be magnified.
My premise is, almost, entirely mathematical and gleaned from boating on the Serpentine in London, you might say. But it did frighten me. However well planned a passage, fog is inevitable but what makes it toxic is the presence of very fast merchant ships who are completely disregarding the Collision Regulations.
For a yacht travelling at 5kn on a collision course forward of the beam with a container ship doing 27kn, contact at 6nm range by radar will be made when the yacht is 1nm away from collision, such is the impact of the speed disparity. The yacht skipper in these circumstances has two options: either switch the radar off and hope the container ship skipper is awake, hasn’t been on the bridge for the last 24 hrs, isn’t shorthanded, is in control, sober and not from some part of the world where human life is cheap, or, assume none of the above applies. There is a case for hitting the off button. The probability of a collision is statistically small but there are circumstances which decrease the odds eg passing close ahead of a container ship doing 27kn which most would instinctively try to avoid and in so doing and by using radar create a radar assisted collision.
My first premise is that if you, the yacht skipper, take more than 5 minutes from first seeing the target to determine and execute your collision avoidance strategy you are heading for trouble. In 7 minutes you are 4 cables away from a collision. There are significant system and human errors which can be dangerously misleading the closer you get.
My second premise is that a stabilized display which at the very least shows a North Up or stabilized EBL is essential. Calculating track, speed, CPA is all but impossible within the time you have available without such help. However, such aids are not of much benefit if you are not skilled in their use. A practical and well honed method of translating observed data into meaningful data upon which you can base your decisions is essential. In this regard, the practice of positioning the radar display in front of the helm is one that I question. Is the helm able to accomplish all that is required?
My third premise is never slow down. The faster you can go, the more room you give yourself. Substitute ‘radar’ for ‘foghorn’ in rule 19e for when reducing speed might be appropriate.
My fourth premise is never reduce the radar range to, say, 3nm. You merely make yourself blind to the one behind it and time is utterly of the essence. If there was only one rogue vessel intent on manslaughter then I could see the point, but there aren’t.
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