Oyster. Rise from depth

Every time and every work have their own symbols. Often, as the eternal symbols are called architectural structures: the Kremlin, the Egyptian pyramids, the Tower, Big Ben. Often, as clear symbolic things, some brands are mentioned, symbolizing certain qualities of the goods and possessing a very high – and sometimes even “unshakable”! – the reputation of high-end manufacturers. For example, Bentley cars. Until recently, such unshakable brands belonged to the British company Oyster Yachts, whose yachts were considered a model of quality, reliability and durability. However, everything has changed …

Oyster. Rise from depth

Text and photo by Artur Grokhovsky


Text and photo by Artur Grokhovsky

The crash of the yacht Oyster 825-02, which occurred in early July this year, for a long time was surrounded by a veil of secrecy. For obvious reasons, the construction company did not want to talk extensively about it, nor did the owner of the boat, which had parted with the dream to bypass it around the world, aspire to wide publicity – and it can also be understood. As the water in the mouth gained and the third party of the process – insurance companies, which is all the more unsurprising. For some time it seemed even that this sad (and almost tragic) incident would fall into oblivion. However, at the end of October, the news came to the YR that the yacht was still ready for recovery and it was urgent to fly to Cartagena, where the shipyard, which was taken from the depths of the Mediterranean Sea, was towed to the local shipyard Ascar. But before telling about the rise of the yacht, about what we saw after,

The journalistic practice is well known: when talking about a situation in which there is a conflict of interests (and here it is fully available), the media officer should present in the article the points of view of all the parties involved in the conflict. Unfortunately, in this case, we will have to step back from this scheme for one simple reason: Oyster Yachts, represented by its head David Tideman, flatly refused to answer any questions (we repeatedly tried to ask both by e-mail and by phone). Moreover, Mr Tiedemann made a lot of efforts to avoid meeting and communicating with us during the yacht exhibition in Cannes, and even during his short (only 30 minutes) visit to Ascar shipyard.

To even more regret, the company Oyster Yachts advised against communicating with us and boat designer Robert Humphrey. It is not known which mechanisms were involved, but in a letter addressed to the editorial office R. Humphrey said that he did not want to see the photographs of the raised yacht made by the editor-in-chief of YR, as well as hear the story of this event from the mouth of her captain, wholly and completely relying in the coverage of this issue on the company Oyster Yachts .

Despite this, the editorial board of YR believes that it has every right to tell the readers about what happened, because we were there, we saw the raised yacht with our own eyes (and thus got the right also for our own opinion), we communicated with its owner, with her captain, we got acquainted with both the point of view of the invited surveyor, and with the view of the director of the shipyard Ascar as an independent expert.

In addition, we are dealing with a unique fact: on an even, what is called, place – not during a storm, not as a result of a collision, not because of a fire, but simply because of the loss of the ballast keel, an 80-foot sailing yacht sank, at the time of death which was on the factory warranty. And this obliges us to make the details of this event public.

Before proceeding to a description of the design and damage to the boat, as well as an analysis of the possible causes of its death, let us give its word to the captain, the Italian yachtsman Alessio Cannoni.

Yacht Russia : Alessio, have you watched the boat from the very beginning of its construction?

Alessio Cannoni: I first showed up at the Oyster shipyard , when the hull of the yacht was already laid, so I did not follow the construction from the very beginning. At first, I was happy – how, I will command the boat of such a famous manufacturer! But after a week of staying at the shipyard, my euphoria disappeared, giving way to exactly the opposite sensations: but these people simply do not know how to build yachts! The number of small and large miscalculations made during the construction of the boat is difficult to enumerate – while the shipyard arrogantly refused and refuses to admit at least one of these miscalculations its mistake.

YR : Let’s talk about these miscalculations later. Tell us what happened to the yacht after its launch – from its owner, we know that the first problems appeared immediately after the acceptance.

AK: By taking the boat (it was in May 2014) we went on a voyage to the shores of Norway. During this trip, a problem with the bow thruster was identified. It has a hydraulic motor and an electrical extension and cleaning system. However, the system proved to be unreliable – when moving against the wave, it did not keep the mine cover in the closed position, from the constant impacts against the yacht’s body, the lid edges began to chip. After this voyage, we returned to the shipyard in Southampton to eliminate this defect (I will say right away, it was not completely eliminated – apparently the weight of the steering device is too large, and the system is not able to tighten the lid tightly with strong pitching).

After the yacht’s rise to the shore, a new problem was discovered, which became our constant headache: the ballast of the keel was loosely attached to the plastic fin, which is part of the shell skin. It was seen increasing in the direction of the stern gap between these two parts of the falshkilya. This was drawn to the attention of the management of the Oyster shipyard. The shipyard dismantled the mast and engine to gain access to the keel bolts. It was found that some of them have an effort to tighten the nuts considerably less than the calculated one (a copy of the document confirming this fact is at the disposal of the editorial staff). The event was recognized as a warranty case, the bolts were re-tightened with the necessary torque (in addition, a massive bronze plate was placed under their nuts for the reliable reliability), the engine and the mast were put back. The warranty period for the vessel was extended until September 2015.

YR: What happened to the ship next?

AK: We went to ARC, after which the owner of the yacht planned to start circumnavigation. Arriving on the island of Antigua, we decided to again assess the condition of the keel, for which they raised the yacht to the shore. And again we saw the same picture: the ballast keel loosely attached to the fin body (the gap between them, as before, widened to the stern), some of the sealing tape came out outside, after the yacht was raised, water left the space between the fin and the ballast for a few more hours. We called a local surveyor, who assessed the problem as “very serious” (a copy of his report is at the disposal of the editorial staff.) – Comment AG. Of course, there could be no question of circumnavigation with such a keel, so the ship owner turned to the shipyard with a proposal to solve the existing problem. Director of the shipyard D. Taidemann in his reply letter (his copy is at the disposal of the editorial staff.) – Note A. G.) called the incident a “cosmetic defect” and advised the owner to “enjoy his yacht”, refusing to recognize not that seriousness, but the very existence of the problem. After that, the owner decided to drive the yacht to Europe, to show it to European surveyors. During this transition, the ship lost its keel, overturned and after a day’s drift in an inverted position sank about 4 miles from the coast of Spain. From the first sounds, which testified that something was beginning to break, about five minutes passed before the boat was completely overturned. During this transition, the ship lost its keel, overturned and after a day’s drift in an inverted position sank about 4 miles from the coast of Spain. From the first sounds, which testified that something was beginning to break, about five minutes passed before the boat was completely overturned. During this transition, the ship lost its keel, overturned and after a day’s drift in an inverted position sank about 4 miles from the coast of Spain. From the first sounds, which testified that something was beginning to break, about five minutes passed before the boat was completely overturned.

YR : Before this accident, the yacht has not been in collisions, has not run aground?

AK: No, there were no clashes, I declare it responsibly and officially.

The yacht raised from the water looked terrible. Based on the photographs, documents, as well as the stories of the captain and the owner, available to the editorial office, I set up a preliminary picture for myself on the way to Cartagena. Actually, at that time, I had no doubt that the keel breakage occurred along the joint line “ballast keel – plastic fin,” the only question is what exactly led to the accident. Reality, however, as usual, has surpassed all assumptions. The volume of destruction (and what I saw to be called precisely “destruction”, and not “damage”) exceeded everything imaginable and unthinkable – none of us, witnesses of the hull lifting, could imagine that a plastic yacht that had not been in a collision could be so hard to suffer.

Why am I in advance – even before receiving official acts of expertise – I take the liberty of asserting that what happened is not the result of a collision of the yacht with any surface or underwater obstacle, as well as landing on stones? Do not I rely too much on the words of the captain and the owner alone, the readers will ask?

The answer to this question is this: in the presence of a group of surveyors, I observed the survey of the leading edge of the ballast keel (it was also raised to the surface). Of course, there are no official conclusions yet (according to the surveyors, they will appear at best in a month or two), but the cleaning of the front edge of the keel from the damaged paint clearly showed (and you can see it in the photo) that the traces of a collision or collision with there is no underwater obstacle on it. Similarly, there are no traces of collision of the yacht with the obstacle and on its hull.

Readers, carefully were watching for reports on the website of the company Oyster Yachts, may again ask : but as the same be with her statements : «There are also photos of scrapings across the hull, possibly caused by a steel hawser and other photos show a rudder broken off at its root, and the other one with its tip broken off “?

To this I can answer as follows: at the disposal of the YR editorial office, there is a video recording made by the crew of the yacht from the liferaft shortly after the vessel is tipped over. The record clearly shows that the two steering styluses of the yacht are not damaged and are in their places. Therefore, it is not difficult to prove that the loss of the right-hand helm occurred after turning the hull of the yacht.

So, what did we find after the boat slowly rose from under the water?

From the body, not just a ballast keel (bulb) came off along the “ballast-fin” connection, it came off together with a fin that is structurally part of the shell skin. Moreover – and this is completely wild and sounds and looks like – the detached keel “took off the scalp from the yacht”: in the area of its attachment to the hull, the outer skin of the yacht (from both sides) from the place of attachment of the fin of the flashed up to the KVL is torn down in an area of about 20 m 2 .

How could this happen? Why did the ballast keel not hold in place the keel bolts? What does the outer skin have to do with it? What kept the keel in its place?

To answer these questions, you should consider the design of the hull of this series of yachts Oyster 825. Why this particular series? Because its design, according to the company, is somewhat lightweight in comparison with the design of its predecessor – the Oyster 82 series, the yachts are heavy and powerful. The displacement of empty yachts of the type Oyster 825 (according to the shipyard) is 56 tons, while 82-foot vessels of the previous generation (again according to the manufacturer) had a displacement of 61 tonnes empty. Five tons of difference (or almost 10% of the displacement) is, sorry, the ram did not swell, despite the fact that the new boat has become even 15% larger inside and noticeably more comfortable.

However, back to the construction of the yacht. The shipyard refused to provide us with a keel attachment scheme, but the consequences of the accident allowed us to study it in the smallest details, as they say, from the inside. Take a look at our reconstruction:

To begin with, the notorious keel bolts did not bind a ballast with the power set of the body – keel beam. These bolts, by the way, are very powerful, fixed the ballast keel exclusively to the plastic fin (in the English language terminology – keel stab). Only one bolt – the most aft – went right through the fin to the hull. (He, by the way, could not be found – if all the other bolts were in place, then this bolt ripped out of the ballast of the keel.) That is, with the actual body kit, the ballast part of the keel (bulb) was connected not with keel bolts, but with only the outer skin and inner set of keel fin.

Is it possible to consider such a design a design or assembly error? The fact that such bolts are assembled by mistake, does not indicate anything – so this is clearly a solution by design. However, one can not consider such a scheme and a mistake of the designer of the power circuit of the hull, as it is quite often found on many modern yachts and approved by various certification and survey companies. You can not … but with the caveat: provided that the circuit design is calculated and manufactured correctly.

And here there is one subtle (in both senses of the word) moment. If the yacht type Oyster 82 thickness of the shell skin in the keel area reached 70-75 millimetres, then this boat … The thickness of the outside hull  layer of the deceased vessel was (according to surveyors) of the order of 16-17 millimeters – and this together with gel coat and anti- in fact, it did not exceed about 15 millimeters (this is despite the fact that the lower part of the fin, the one for which the keel bolts held, had a thickness of 45-47 millimeters). The internal transverse bulkheads of the fin (bracket) had a thickness of only about five millimetres.

In other words, the entire mass of the ballast keel (and this is of the order of 20 tons) was kept on the hull of the yacht due to the 15-mm fiberglass skin of the hull, passing into the keel fins (the body and fin of the keel are pasted in one die, this is a single piece), and five-millimeter internal bulkheads (marriage). And the plating could not stand it – it broke in the literal sense of the word.

“So what happens? – attentive readers will ask again. – So, was Oyster Yachts basically right? The notorious bolts were, in fact, nothing to do with? ”

Yes, nothing to do with it, but only formally. And then I remember an episode from the memories of a man whom I consider to be one of my teachers: test pilot, Hero of the Soviet Union Mark Lazarevich Gallai. The attitude to this case, he has the most direct.

During the test flights “overload” on the Yak-3 fighter (the case took place in May 1945) after the first landing of the aircraft, the striped pin signalling the normal release of the main landing gear rails came out not through the nominal opening, but through the wing skin.

“… The aeroplane was inspected, but no special criminals were found. Strange behaviour of the wayward pin of any convincing explanation has not received. The damaged part of the plating was repaired, and the aircraft was found to be suitable for further flights.

It is very tempting when there is urgent work and it threatens to interrupt some incomprehensible, demanding reflection phenomenon, to call this phenomenon nonsense and to take out a vigorous resolution: “Do not pay attention”. And this time (as, alas, and in many other cases), this mighty temptation easily prevailed over the weak voice of reason, which, of course, could not quite be completely silent in the minds of the people who directed the experiment.

“Yak-the third” was returned after inspection and “cold repair” to the airfield and, now controlled by another pilot – SN. Anokhin again broke away from the concrete strip.

But it was not possible to carry out the task safely to the end of Anokhin. Having started the next figure, he heard a loud crack, and at the same instant, the car rushed to the side so sharply that the pilot with terrible force struck the temple with a lamp and his arm and shoulder on its side. The wing flew off the plane!

The pin of the mechanical chassis position indicator honestly signalled the “third bell” before the destruction of the wing – its dangerous residual deformations that arose in the previous flight. And yet such an obvious signal remained misunderstood and not taken into account. This is generally more frequent than it is commonly believed that a car before “bucking” warns people about its bad intentions. But warns almost always barely audible, as if in a whisper. You must have a subtle, sophisticated rumour to hear it. Here the machine did not whisper, but, it can be said, loudly, into the voice shouted about its malfunction. Why was this voice not heard? I think that not because of the lack of qualifications of the managers of the work, but primarily under the hypnotic influence of the notorious “come on, come on!”.

I admit that in this case, the motives for not paying attention to the obviously abnormal behaviour of the ballast fin from the leaders of Oyster Yachts were completely different, but everything else is exactly the same. The machine (in this case, the yacht Oyster 825-02) signalled serious problems with one of the key elements of its design – with a ballast keel. However, manufacturers preferred not to pay attention to this signal. Fortunately, everything was more successful than in the example described above (S. Anokhin then lost his eye) – no one was injured, the crew thanks to the skilful actions of the captain managed to give a distress signal and safely land on a life raft, from where he was later saved by Spanish fishermen. So what happened on board the yacht on that ill-fated day on July 3, 2015? We will again give the floor to Captain Alessio Cannoni:

YR: Alessio, how did things happen on board at the time of the accident?

AK: We walked in the afternoon to the coast of Spain in an acute coastline (about 55 ° to the true wind) of the right line at a wind speed of about 18 knots. One man was on the steering wheel, the rest of the team was resting inside the boat. At 14:06 nothing boded ill, and I went downstairs to check the laying of the course. At 14:08 there were loud noises inside the building, something like “cr-cr-cr-cr”, while there was no feeling of hitting the body or keel about something. The sounds resembled a series of shots. Then there was silence, but the boat began to noticeably slow down the course and at the same time began to roll harder under the wind.

At first, I thought that in the engine room – right under my feet – something heavy fell off and fell on the leeward side. Maybe a generator, I thought. However, before I could tear myself away from the chart table, I heard the usual noise of a normally working generator and a desalination plant. The next thought was the suspicion that we hit something like a buoy or a floating log.

I went upstairs and looked in the wake – nothing. The helmsman said that he did not see anything either. It became obvious that the source of sound origin is located inside the yacht. And at that moment I heard an alarm: too high a level of water in bilge bilges. My friend Daphne, who performed the role of the Stateroom on the yacht, woke up and left the cabin. Being at the top, I ordered him to check the bilge. He opened the door to the engine room and immediately screamed that it was completely filled with water.

Then I still did not represent the true scale of the disaster, having decided that a part of the keel bolts had burst. I dumped the boat for a full course to reduce the roll and, accordingly, the moment acting on the keel and its bolts. Then he told Daphne to give the signal “Pan Pan”. He asked: “Are we drowning?” I answered: “No”.

I tried to remove the sails. But the twist of the staysail and the mainsail did not work – only then it became clear that the fin detachment came just in the place where the main batteries are located, they were flooded first.

The peculiarity of our yacht is that without the main (service) batteries it is impossible to start the engine even if its starter batteries are in good order. This is one of the mistakes I mentioned earlier. The shipyard refused to fix this on our boat under warranty but kindly informed us that on subsequent buildings of this series such a problem will no longer be.

The bilge pumps were not working. We also had a mechanical (not electric) pump, but she also demanded a running engine. We ended up without a single working system on board – except the emergency hand pump with the drive from the stern lock.

At about 14:10 the whole team was already upstairs, and I tried to clarify the situation for her. The son of the owner of the yacht rose to the wheel. Daphni was on the radio talking to the Coast Guard. Two people, I put to the pump, another ordered to prepare rescue equipment.

I manually twisted the sails as much as I could. When I was tortured with a staysail, I noticed that the yacht continues to land with its nose, and from the freeboard, in the nose, it remained good if fifty centimetres. We were drowning.

I ran into the cockpit, looked down – in the cabin the water was above the level of the sofas. It was at 14:12. It became clear that the pump can not cope and it’s time to tell the team that the plans are changing: we stop fighting for the survivability of the vessel and are preparing to leave the yacht.

We pulled the life raft out of the nest. I gave the signal “Maidei” on the radio, informing our coordinates (standing at the knee in the water in the literal sense), grabbed a few life jackets … At that moment, the keel broke away completely, and the yacht began to tip over. Between the first sound of the rupture and the beginning of the overturning of the yacht, it took only five minutes …

The overturned yacht due to air bubbles kept for about a day on the surface of the sea. Then she sank. It happened about 4 miles from the coast of Spain.

As you can see in the photos (they say about what happened, perhaps, better than any words), the keel, coming off, “pulled off” a piece of skin from both sides. In fact, it should not be said that the keel has come off, but that there has been a delamination of the hull on an area of the order of 20 m2. The photographs clearly show that the inner part of the skin, which was individually peeled off – with the formed stringers and floras (which turned out to be hollow) – was almost intact. Almost, but not quite: in some places, the outer skin, “leaving” to the bottom, tore up pieces of the inner skin, separately pasted into the soap box. Through the holes formed, water began to flow, which destroyed the yacht.

What is the reason for delamination? Low-quality resin? Is its lack in the laminate? Low-quality insertion of the section of the internal set into the case? Or was it simply that the keel mass was too great for such a thin outer skin? And why this skin was so thin?

At the moment there are no official answers to these questions. In several places of the hull, pieces of both plating and set were cut out. In our presence, they were sealed and sent to England for examination. It should clarify what the quality of the laminate was, what its strength was, and finally, whether it was enough to hold the bulb.

One of the “discoveries” made by the captain during the construction of the yacht became an incomprehensible designation of a permanently moulded compartment in the bow that was absent on the ship’s drawings. The shipyard refused to give his appointment, but informally one of the workers said that a ton of lead had been moulded there to compensate for the trim on the stern. Believe in this was difficult, but the boat accident allowed to open this compartment. It is completely filled with ingots of lead and lead shot with a total mass of about 800-900 kilograms. Just imagine that when you move against the ocean wave at the very nose of the yacht are 10 people. This ballast added a yacht a differential moment on the nose equal to 9 tons. To achieve the same effect, it was enough to move the ballast falshkil in the nose only 40 centimetres…

The official conclusion, therefore, is yet to come, and it will take about six weeks to wait for it. However, we have unofficial views expressed by people who had the opportunity to study the remains of an unfortunate vessel.

Although most surveyors refused to communicate (we were even asked not to photograph them “from the face”), one expert – Ramon Cardenas Valero, inspector and marine engineer (Ingeniero Technical Naval), a member of the survey company Comismar, invited by the insurers to assess the causes of the death of the boat, agreed to share their views on what happened.

Ramon Valero: I believe that the cause of keel loss is in the thickness of the fin skin. Look at the thickness of the fin where the ballast keeps the keel bolts, is about 50 millimetres: this is quite normal for such a mass. But then these five centimetres of the lower part of the fin go to fifteen millimetres of its lateral part, and this is completely unsatisfactory. Traces of impact or collision, I did not find. Yes, there are minor external damages on the case – here, we marked them with chalk and numbered – but they obviously can not be the result of a collision of such force that the keel breaks off along with the skin.

YR: What about the amount and quality of resin in the laminate? Do not you think his pieces are too “dry”?

RV: Yes, this is also a possible reason, but an accurate answer can only be given by laboratory analysis.

His opinion was shared and the director of the shipyard Ascar Francisco Fernánes Garcia. I note that his opinion is especially valuable since he is an independent party – Garcia does not represent either the interests of the owner nor the interests of the shipyard builder, does not participate in the survey, does not collect material for the press. He only provided a platform for the ascent and shore storage of the yacht, and therefore could speak freely about what he saw. We talked with him when the yacht was still hanging on the lines of the crane – the water from the hull was pouring out almost a day, and when the boat was still put on the blocks and we went down inside, a little octopus lodged behind the navigating table, and in the corridor leading to the owner’s cabin , settled quite aggressive moray …

YR: Francisco, have you ever seen anything like this?

Francisco Garcia: I did not see and did not think that I would ever see. And I’m sure that I will not see such a thing again. Absolutely incredible, just unimaginable damage! Yes, even on an almost new yacht. I’m not sure, but it seems that this case is completely unprecedented.

YR: What do you think, what is the cause of the accident?

FG: Insufficient thickness of the shell of the body and transverse bulkhead fins. Now, look: these are only 5 millimetres thick. When the yacht came with a roll, the main compressive load from the keel accounted for precisely these bulkheads, which kept the shape of the fin. It’s just paper, cardboard! I worked for seven years at another shipyard in Spain, we built sailing catamarans, so we had more reliable structural elements.

Editor’s opinion

I have my own opinion. It seems that the process of keel loss developed as follows … During the course of the boat with the roll, three types of loads influenced the keel attachment elements: the load on the weathering side of the fin on the windward side was applied (its plastic laminate perceives relatively well); from the leeward side – the load on the compression (in itself, fiberglass does not hold the compression load at all; in the laminate, only the resin takes up the compression load, so its compressive strength can be several times smaller); on the vertical bulkheads inside the fin, there was a combined load on compression and bending (its fiberglass is also not very fond). It is these bulkheads because of their small thickness, and this manifested itself during the first voyage of the yacht, They did not sustain dynamic loads, having lost the stability of the section and began to deform. Thus, the keel fin sheath has lost the rigidity provided by the internal set (these same bulkheads) and began to “breathe”. It is the loss of stiffness that explains the reason for the appearance of a gap between the fin and the bulb, since in principle it is impossible to attach a heavy rigid part to a relatively elastic skin so that the gap in the interface between them retains a constant and unchanged width during work under alternating loads.

Probably – and here I do not fully agree with the opinion of the captain of the yacht – the destruction of the shell did not begin on the windward (right), but on the leeward side: that is, where the sheath worked on compression; At the same time, internal bulkheads were bent and finally detached. In favour of this version indicates that the area of damage to the skin from the lee side is much larger: the damaged area comes above the KVL, exposing the filler of the sandwich, while on the windward board the damage ends strictly at the level of the KVL.

And then it happened: after the yacht’s transition to the full course and the reduction of the roll, the fin casing began to work on stretching, transferring the mass of the falshkil to the side skin, while the internal bulkheads (brackets) were already broken and/or torn off and did not take the tensile load. In this situation, the outer sheathing of the bead began to work on shear, and the strength of GRP composites to shear is approximately 15 times lower than the tensile strength. Sheathing could not stand – there was a shift in the outer layers of the laminate with respect to the internal: the outer layers of the fibreglass crawled downward, under the influence of the mass of the keel, tearing away from the inner set and opening the way to the water inside the case.

Reasonable question: why such an accident did not occur on the boat Oyster 825-01? A possible answer to this question was given by Alessio Cannoni: in the time that has elapsed since the launch, the yacht has travelled across the ocean many times greater than its sistership. And as it became known to the YR edition from private sources, after the accident with the yacht, Oyster Yachts company strengthened the sides on all the already built boats of the Oyster 825 series …

PS Exactly three months, we tried to get from the company Oyster Yachts at least some comments about what happened. That’s all that David Tideeman, the director of Oyster Yachts, was able to say after he got acquainted with the results of our investigation. At his request we post this comment as an official opinion of Oyster Yachts:

Oyster continues to assist the investigators of the loss of Oyster 825-02 and has had a team of experts who attended the vessel for several days in Spain since her recovery in late October. We understand that the investigations are carried out and that the official public statements will be made. Oyster believes that the interest of the owner and other stakeholders is the best served by waiting for the investigation to be completed. (“The Oyster company continues to investigate the causes of the loss of the Oyster 825-02 yacht and sent a team of experts to Spain in a few days at the end of October.” We understand that the investigation is a long process and our public official announcement will be made after its completion.


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