Originally Posted by Erin
I personally don't find that 'too cluttered'. There's clarity in the direction of each vessel and therefore which ones might become a threat. If you are doing close quarter manouevres in a busy area then surely by zooming in you will 'space out' the targets. Interestingly, the heading line on all markers is the same length. On my Garmin it's length varies depending upon the speed of the vessel which helps you determine which are approaching fastest.
If you set a filter, does that also affect automatic collision warnings or do they still sound the alarm.
Yes, your quite right, it was'nt too cluttered today but as C2Ribs also says, today was just an ordinary day.
During busy weekends when the sun is shining and a good breeze is blowing the number of targets shown can easily tripple.
Cowes week and the ''around the island race' are a complete nightmare.
Imagine your a pilot trying to bring in to port a large container vessel or tanker, VTS tells you that an outbound cruise ship is nearing the 'clear channel vessel' area meaning that only one vessel can be in the area at any time (hatched area on the chart around the west Brambles bouy, the cruise ship is south bound and your north boaund) . Now your too far away to visually sight the cruise ship so you check the plotter to see where she is. Imediately you realise that her name is already partly obscured by a yacht sailing close by and secondly, when you pan back out, the target practically disapears under a splattering of class B targets.
As pilot, your now having to rely on radio communication with both VTS and the southbound cruise ship to determine where she is rendering the AIS system (which should be a valuable tool) useless. This also creates distractions for both you as pilot of the container ship and also the pilot of the cruise ship who could very well be having the same problem.
VTS filter out clas B stuff for similar reasons, they have to track all commercial traffic entering or leaving the port. They keep an eye out and (believe me when i say this) they are very quick to call up any wayward vessels that should stray outside of any channel or be on a collsion couse with another ship or fixed object.
Yes, all our vessels can set the track to vary dependant on speed of the target but here in the ofice we dont normally bother.
The real question once again has to be " did all those leisure vessels on the screen shot really need to be transmitting? "..... Most of the targets on the screenshot were yachts, so do we really believe that those yachties were paying attention to their chart plotters (the ones that actually have a plotter screen by the helm and not down below near the chart table).
Ask any Master or Pilot of any commercial vessel what his primary means of collision avoidance is and they will probably tell you their eyes...actually looking out the window and seeing what is happening rather than relying on electronic tools.
Now, as i have previously mentioned, when it becomes difficult to actually 'see' ie: night time, fog or other poor visibilty conditions or when your in a situation where commercial traffic would not expect to cross paths with a leisure vessel ie: crossing a TSS or other busy offshore channel, then yes, use the AIS but otherwise keep it switched off.
A short term solution to the problem would be to have commercial targets appear in a diferent colour than leisure targets, not perfect but a good start.
Ian, yes, the Iphone app (ship finder) is very good, many of us use it when were not around a chat plotter.