“Båker” (“båkene” in multiples) are unlit navigation marker made from wood and marked on the charts. There are hundreds of them along the Norwegian coast, along with “Varder” (made from stone) and “jernstenger” (iron rods) There are about 12000 of them in Norway.
From the Coastal Authorities official description:
VTS and communication will almost certainly have played a part in this event.
Why did VTS not know the HI was approaching and inform the Tanker.
And of course why did VTS not update the HI about The Tankers Departure.
Idle speculation on my part.
The HI entered the VTS area and reported she would be “operating”. Taken by VTS as Conducting some form of trading or exercise in a particular area.
Rather than transitingthrough the area.
VTS ither misinterpret HI intended route or VTS was not informed by HI of route and ETA to next call in point.
Tanker was given inaccurate information about HI on departure or not given information about HI.
VTS can provide useful information, if they receive useful information in the first place.
If VTS had been aware the HI routing was to pass the oil terminal with an ETA at next call in point.
Passing this on to the Departing Tanker may have influenced the Tankers actions.
If VTS were aware of the HI intended route and ETA. VTS could have updated the HI on the Tankers departure.
If one or the other vessel or both vessel were aware of the others routing and the probability they would meet. They might have had a more effective VHF communication and arranged a safe passing arrangement.
VTS can be very helpful.
Or sometimes not so much.
It sounds like the VTS just surmised it was the Helga Ingstad, perhaps they had not received a complete report.
The issue is the AIS in my view. If 99.9% of vessels are using AIS that makes it more likely the ones without will be missed, just human nature.
The weight or displacement of an intact ship could be measured in a dry-dock, floating or not:
The difference of the water volumes pumped out of the floats or the basin to have the bottom dry, without a ship therein vs. with the ship.
The weight of a sunken ship, full of water, is her displacement minus the buoyancy from the water displaced by the ship’s hull sheets, the immersed superstructures and the internal structures and equipment, and all voids not filled with water. This is pure Archimedes.
Your linked text gives the exemption where your Newton does not apply:
When launching heavy objects at sea you must add 75% to the static weight of an object to account for dynamic loads (load X 1.75). The only exception is if you have actual measured accelerations for the ship you are on.
The Fjords are like smaller, tortuous lakes without swell. If the interior weather is bad, you just delay the action.
I recall the ‘Newton vs. Archimedes’ discussions with the lifting and towing of Costa Concordia’s wreck:
Lifting the wreck from the artificial seabed, by emptying the water filled sponsons, was so slow that Newton was irrelevant; it was Archimedes only…
Towing the wreck was a Newton thing. The tugs had to accelerate or decelerate the wreck’s whole weight and the water inside the wreck’s hull.
I agree with that; in the past there were navigators on the bridge. They have been replaced by navigation system operators, where the least of effort gadget will be operated.
If we play back the video again and again, we can observe 3 different AIS vectors transmitted simultaneously by Sola TS and escort-tug Tenax. I have enlightened those vectors; the main vectors being in white while the two others in magenta. KNM Helge Ingstad shows only one main vector in white, even if her AIS was reported off. Which one of these vectors were observed from KNM Helge Ingstad system ?
On the left picture, KNM Helge Ingstad is almost totally outside on the Stbd side of Sola TS AIS white vector, while she is rather on the Port side of the two magenta vectors. Minutes later, KNM Helge Ingstad is totally outside of Sola TS white vector but directly in the direction of the two magenta vectors. Since KNM Helge Ingstad was on the Stbd side of the white vector, did she rely too much on AIS and assumed that she would clear Sola TS on green to green ?
Yes of course, you are quite right, that weight has to be deducted which changes the picture of lifting the sunken ship.
Anyone have a nautical chart of this particular area? HI did not want to turn starboard out of concern of grounding on the rocks. Google earth shows what looks like a shoal at a distance of .32nM and bearing of 128 to 130 degs from the position where she sank. It appears that HI was trying to pass between Sola TS and Silver Frida…she should have made het intentions clear…the communication between the two vessels and VTS is extremely poor to say the least!
If I was driving a Z-peller tug I would just lay back on the line until I was required to do something. I’ve done the same thing on AHTS on a static tow with an off take tanker approaching an FPSO. There is no slack in tow line if you’re required to do something.
The way this collision happened has, given the expertise we expect in an armed force that the people in our Norwegian correspondent pay a great deal has just left me incredulous.
So Norwegian frigate KNM Helge Ingstad (HI) is speeding at 17 knots in pitch darkness on a secret mission outside an oil terminal and sees four merchant ships/tug heading towards him on the port side. Instead of continuing at same course, HI decides to turn port (!!) between the four ships. The bulbous bow of fully loaded, double hull M/T Sola TS leaving the oil terminal then, while turning starboard, contacts HI’s starboard side and rips it open below waterline, HI heels to starboard and rips off the starboard anchor of Sola TS, bow flare of which rips open HI above waterline, etc. Sola TS has a tug attached aft. The fourth ship, M/S Vestbris had to turn 90° port to avoid HI, Sola TS and the tug. Luckily it was not HI ramming or ripping open the port side of Sola TS which could have resulted in an oil spill and fire.
I wonder if Norwegian military ships have Voyage and Voice Data Recorders fitted. They would tell what happened on the bridge of HI. Anyway, warships should stay far away from merchant vessels at all times.
As in most collisions I believe the blame will be shared, for sure, both HI and Sola TS could had done more to avoid collision.
The expression navigational exercise can mean a lot of things, apparently the AIS was of on HI, what instruments (lights, radar, etc…) that was on we don’t know, I have sailed on tankers with Captains that didn’t like to use the radar too much(before GPS and AIS).
All communication from Sola TS to third parties was in Norwegian although for sure none of the other parts of the bridge-team understood Norwegian. I have myself (Norwegian) many times been at the terminal, and all navigational talk were done in english, only chit chat not related to the safe navigation of the ship was done in Norwegian.
The main lifting will be done once the wreck is in position on the submerged barge, not by the cranes.
The damages to the hull and intact strength probably answer for the need to use two cranes with 4 main hooks to do the transfer from the present position to the barge, not the max. lifting capacity of the cranes with the booms in near vertical position and short range.
A post was split to a new topic: Ship Assist Tugs
It doesn’t look simple to remove the wreck. It rests at less than 20 meters depth on its side. It is a total loss. 7000 tons scrap is worth say $1.5 M. Two big barge cranes lifting it, still on the side, on a barge is just a waste of time and money. You have to install plenty wires, etc, around it. So it is best to leave it where it is, in my opinion. I would just remove any guns, ammunition, fuel and oil aboard.
Tks for posting the chart By-C. Total lack of situational awareness on HI…
Well… there are a few antennas and light bulbs to salvage ! 
Actually it is the other way around. Hence the saying “If it is gray, stay away”.
Just Saying …but in the news recently there was a report the the Russians were interfering with the European GPS system during the NATO exercise. Hmmmmm any adverse impact on navigation in this collision?
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