[b]AIS information or lack of it[/b]

[Dann]

[b]AIS information or lack of it[/b]

I have recently purchased an Easy AIS engine and a Northstar 567 (same as Navman 5607) plotter and used them on a couple of cross channel passages and found the AIS extremely useful. However I feel that the information given by the AIS function could be greatly improved if as well as CPA and TCPA it included whether the target ship would pass ahead or astern or to port or starboard. eg: if a ship is shown as approaching at 18knots at right angles with a CPA of 0.2nm and one wishes to increase the CPA, does one slow down or speed up or change course one way or the other? This I found was not easy to ascertain and had to use good old fashion eye sight and changing angles - not available in poor viz! Surely this could be easily computed by a plotter and included in the information, or am I missing something ? Generally, I feel much safer if I know a ship is going to pass ahead of me rather than the other way round! I would be grateful to have other forum members views.

 

[shmoo]

Re: [b]AIS information or lack of it[/b]

On SeaClear with NASA engine there is a "projected track" line out of each AIS target and out of the "Own Boat" icon. We extend the the projected track to 900 sec (1/4 hr) when in the open sea.

 

[ParaHandy]

Re: [b]AIS information or lack of it[/b]

I haven't, yet, seen a plotter with integrated AIS that is as well implemented as some of the PC based AIS programmes eg shipplotter. your question bothered me as well until i worked out it was quite easy (on shipplotter) to adjust the predicted track vector so that the actual crossing point (whether behind or in front) was shown. You might be able to do the same on yours?

 

[fireball]

Re: [b]AIS information or lack of it[/b]

We have the SHorizon C180i with AIS engine feed (from the Nasa Engine) and I agree - CPA is fine - but is it infront/behind etc - ie what action would be suggested to make the CPA larger.

I checked the C180i instructions - there is no option to extend the course line for the target vessels - although this would only be of use to the TCPA - at which point you can see where it occurs!

Come on then Chartplotter makers - update the Software so your units can do this vital bit of calculation!