come on the warning was made by the Fedje VTS center who were presiding over the navigation inside Hjeltefjorden Fjord and according to the law any ship longer than 80 feet if wants to navigate in that fjord must be in contact with them from 1 hour before entering Fjord
https://www.maritime-executive.com/article/wrecked-norwegian-frigate-was-warned-prior-to-collision
and again the tanker was full of oil so they simply could not made maneuver in the fjord
and here you can see the Radar that show the movement of the two ships before accident and it seems the frigate actually increased its speed so it can be in front of the tanker.
https://www.vg.no/nyheter/innenriks...-sola-ts?utm_content=row-1&utm_source=vgfront
Again, I am going to say this.
We don't know the circumstance on the collision, and yes, even if an oil tanker is laden with oil, they can still be able to avoid a collision.
The only thing you need to do is to stop the ship in the ford, you don't need to "manoeuvre".
Also, you do not know what happened to the "Warning" to the frigate, maybe the Frigate had changed course heeded to the warning? you don't know, maybe the frigate did not know it was them they were hailing? you don't know about that either. Maybe nobody is staffing the radio room? Or Civilian Band was not monitored? Or even maybe the control room is hailing the wrong ship? You don't know about all that...
How about the reaction of the tanker? Did you know if the tanker know the collision is imminent? Did you know if the Pilot House is staffed? Did you know if the Tanker were actually correcting their course?
As a Police Investigator with 4 years investigation/intelligence experience. You don't know mean you don't know, you cannot assume you know the answer because if you do that, you based every of the subsequent argument on an assumption. Which will bring you further away from the truth.
What we do know at this point is that the Frigate is travelling southbound and the tanker is travelling north bound, and the frigate is hit from the Starboard Aft side. Which mean either the frigate or both ship have manoeuvre out of their original course (otherwise it would have been a head on collision) now, we don't know whether both follow the rule and turn port, or one turn port and one go straight up (If this is this instant, then the Frigate had move and the tanker didn't) that is the only information we know for sure at the moment.
So, with so many factor unaccounted for, again, how can you laid blame on either or both side? I know for sure as a fact, as an investigator myself, I would not have enough information to make even an educated guess, let alone assign blame on this point, unless you know something that I don't, I don't think you can do that either, and it best to let the investigation run its course.
In an collision course, ships are to adjust their course to port (left) to avoid collision, and if both ship were turn to port, then both ship will NOT collide.
From this radar plot, if this is indeed the actual radar return, we can clearly see Helge Ingstad had indeed turn to port to avoid the Sola TS, but Sola TS did not change course nor stop, which accounted for the Starboard aft collision toward Helge Ingstad.
So if in this case, the Cargoship is then violating the International Maritime Law, because it dictated that both ship were to turn to port if both ship is on a head on collision course.
But again, I am not sure if this is the actual radar plot or have anything changes in between, even so, I still cannot say which side is at fault.