Hi All, I hope this discussion has not completely died.
I (and probably many other potential OpenCPN
users) need to be able to disable Class B - or at least put heavy filters on traffic (disabling specific vessels, groups of vessels and other complex groupings) AIS data. I sail in the Solent and virtually every day between March and October there is at least 1 keelboat race
on in the solent and the problem is that the major race organisers (e.g the RYS and RORC) are using AIS to track vessels.
This leads to the situation where I have vessels that are tacking frequently in fleets of 40 or more boats - sometimes several hundred boats in a race (the RTIR race in June has about 1800 entries). They may be briefly heading in my direction, but will turn long before they get near me. They just add clutter to the screen
So I have used the filtering available - I have OpenCPN
set to warn of a CPA of less than 1 mile, but only if it will happen in the next 15 minutes (TCPA < 15), I've also disabled calculation of CPA on vessels more than 20 miles away.
So we have multiple 300ton commercial
vessels doing 15 - 40 knots, I have fleets of boats (Sunsail alone have a matched fleet of 40 Beneteau
First 40's - all with AIS transponders and all tacking all over the place) plus other race fleets (on events
run by various of the 20 or so sailing clubs in the area) all showing and creating traces. I need to leave the settings I've set for any passage
I am on, but around the Solent on daysails the situation is very challenging.
My OpenCPN drives a 19 inch (1440 x 900) screen and I usually have something like a 3 to 5 mile range showing on the screen - and if will often have 20+ danger
tracks showing from all these yachts.
The problem is that all these yachts are tacking and manouvering and their tracks hide the tracks of the commercial
traffic I do care about. Most of the time I can easily predict where the commercial stuff is going, but sometime they make mistakes
, or go somewhere unusual and with all the clutter on the screen it is really difficult to spot this. An AIS CPA warning on this might make the difference between safety
and an incident - if I can spot it!
This is not a 1 off occasional situation, it's most weekends and many weekdays in this area. And whilst I completely agree that I'm keeping a lookout for the race guy's (usually trying to work out what they are using as marks - so I can predict where they are going and when they will tack - last thing I want to do is head
for a buoy and find they are using is as the turing mark at the bottom of a downwind leg - dropping kites and then heading off on different tacks to get clean air!)
On a busy sunny saturday there will be upwards of 5000 vessels in the Solent -increasing numbers of these are fitting transponders and using them in harbour. At present the ONLY option is to disable AIS completely on these trips - something I'm loath to do as I really think it's a fantastic safety
aid (and I think OpenCPN's display of CPA is just about the best there is!)
Any suggestions on how to filter this out ?
for me - I'd like to be able to deselect individual vessels -and to build a database of the vessels I've recieved AIS messages from (So I can tell OpenCPN to ignore the Sunsail fleet for example) This would also speed up the identification of vessels as a side effect. Might be nice to be able to group vessels to watch but disable alarms from (for example to watch a race start for example).
The comments about filtering out Class B being dangferous is right in principle and when on a passage
in a lightly traffic'd area. But a screen that is unreadable because of all the warnings and (irrelevant because they will tack and are not following the channels) red targets showing is worse - and the targets hide and confuse the nav information being displayed as well.
I hope this is seen as a real situation that needs help and not an awkward thing to be ignored, I'll get some screenshots in a couple of months time if you don't believe what I'm seeing is real - I have to add that OpenCPN is a great package and I'm not aware of any commercial package or product with a solution to this problem.