[dagw]

I wonder is if their own AIS monitor was also off? Why didn't they see the AIS signature of Sola TS and the other ships?

According to the commission looking into the accident they did have AIS-monitoring on and had spotted and identified the 3 other ships on their right (which may explain their initial reluctance to turn right, into their path). No one has any good answer as to why they failed to spot/ignored the tanker even as it moved towards them.

[Tor3]

Well.. those other ships weren't really on their right (at that time). They were on their left (as can be seen on the video of the radar monitoring). The reason stated by Helge Ingstad's radio operator for not turning starboard was because of some reefs to their starboard. At the time of the crash those reefs were still 750m away (to starboard) though.

[dagw]

They were on their left

You are of course completely right. I apparently can't read maps or forgotten which hand is which :)

[AnimalMuppet]

I could be wrong, but 750m seems to me to be not very far when traveling 17 knots.

[Tor3]

That's true, however at the time of the collision the dangerous reefs were about 90 degrees to their right. Compared to steering just a vee bit to starboard to avoid the collision the 750m starts looking very wide indeed.