Right hand down a bit No1, "quick as you can " please

[Kukri]

You learn something everyday. I didn't know the maritime industry used land based radio beacons to guide ships. I would have thought the limitations of an airport ILS system would not have been much use for commercial shipping.

The ferries operating to the Aland Islands from Stockholm and from Finnish ports a special case. Because of the Customs status of the Aland Islands, these are “booze cruises” and very much more in demand than simple trips to Mariehamn to admire the “Pommern”, lovely as she is, might be. The routes involve an exceptional amount of rock dodging.

 

[Achosenman]

The ferries operating to the Aland Islands from Stockholm and from Finnish ports a special case. Because of the Customs status of the Aland Islands, these are “booze cruises” and very much more in demand than simple trips to Mariehamn to admire the “Pommern”, lovely as she is, might be. The routes involve an exceptional amount of rock dodging.

The ILS system in use for aircraft is a ground based approach beacon used from about 1945. A primitive version was around in 1929 It provides information for the aircraft onboard ILS receiver. This allows the aircraft to fly an approach to landing following the localiser and glideslope signals to published minima.

Do you mean commercial ships use an equivalent of what we would term as LNAV VNAV modes in aviation? This uses derived positional data to follow along a pre-determined track from start to finish including executing any turns within defined parameters?

It was only a matter of time before commercial ships caught on. Now, if only we could teach them to use track up on the plotter...?

 

[Kukri]

Above my pay grade, but what little I understand of these ferries is that they have been using a system like that for quite a while. It is a special case of close navigation at speed in narrow channels in semi sheltered water.