Ehime Maru relocation brief


U.S. Pacific Fleet Public Affairs

Oct. 9, 2001

Rear Adm. William Klemm (ret.): Thank you all for coming again. We're here today to update the status of the Ehime Maru recovery operation.

I want to pick up basically where we left off last time. The last briefing that we had we discussed the current condition of the ship at that time which was the configuration that you see here in this drawing down by the bow, and with a messenger line passed under the stern. Basically we took advantage of the fact that the stern was off the bottom to install a lifting plate. We pulled the lifting plate underneath the stern and installed that and then began an operation which included dredging out around the anchor hawse pipe that you see here and cutting the anchor chains, and I think most of you realize that we've already removed the anchors and brought them ashore. The status at this time was the beginning of the rigging of the bow so that we could lift the bow up out of that hole that it sits in. The remainder of these slides will show you how we accomplished that feat and what our current status is.

We passed a large bridle assembly down through the haws pipe, on one side and up the other, and connected it to one of the linear winches up on Rockwater 2. We took the other linear winch from Rockwater 2 and attached it to the stern. We made up the lifting strap aft, and then lifted the entire ship by the stern strap and by this forward lifting bridle.

We were very much concerned, of course, that the damage the ship in this area would give way or potentially deflect. That did not occur. The structural integrity of the ship was greater than anticipated as we had said in previous briefings, and as a consequence, this lift went without a hitch.

We placed the ship down on top of the forward lifting strap and that strap then was adjusted to center it and was then made up to the spreader assembly. And the bottom line configuration of the ship as it sits today is with the full lifting frame and both lifting straps installed. It is ready to be lifted.

The top frame assembly was raised back up to Rockwater. They came back in port on Sunday to re-rig the forward sheave to the linear winch. That rigging has been done, and at noon today Rockwater got underway to return to the deep water site.

What we anticipate now is once Rockwater is over the site they will lower that top lifting frame, interlock into the spreader assembly, and Ehime Maru will be ready for its final transit.

This status, if you will, is a projected status, obviously. We have not lifted the ship yet. And I wanted to point out that there are a number of conditions that will permit us to safely make this lift and transport the ship into the shallow water site.

The first is the sea state. We're seeing anywhere from eight to ten foot seas out in between the islands right now. We have very strong tradewinds, 30 knots and gusts higher than that. Wind-driven seas are pushing our total combined sea state, so we expect that somewhere around Wednesday night or Thursday this front will pass north of us and as the high pulls out it will leave behind a reduced tradewind. It won't go down as low as it did a week ago. We still expect 15 to 20 knot winds. But that should get the sea state down into a range where we can make the lift safely.

It's important for everyone to understand that just the size of the waves is not the only controlling factor. The period or the time between the waves is extremely important. As a consequence, the on-scene commander, the folks that are out on the ship will actually make the call when it is safe to lift the Ehime Maru and begin the movement operation. Right now we would not expect that to happen before very late Wednesday night or Thursday morning at the earliest.

Once we have in fact lifted the Ehime Maru in this configuration we will go through a series of checks. There will actually be three ROVs involved. One of the ROVs will do an under-body structural examination; one will maintain a watch on the lifting equipment above the ship; the other one will do a quick survey of the ship and then precede the ship as it moves into the shallow water site. So there's a complicated affair here that's orchestrated to ensure that the ship and the lifting equipment is stable and prepared to make the move. That will take several hours.

Once we start moving the ship to the shallow water site the expected speed when we start will be as low as .2 knots. That's very, very slow. It will be almost imperceptible to the eye. It will take hours and hours to travel a mile at that rate. So no one should expect that we're going to see a wake following behind this ship. In fact Rockwater will probably be backing in with its bow into the seas, and depending on where the seas come from in the period may rotate itself so that it's traveling sideways as it comes in. When it transitted from the deep water site into port on Sunday it did transit sideways all the way through the downtown channel into Honolulu. That's because the lifting equipment is oriented perpendicular to the hull. So in order to reduce the drag and in fact make the ship, the Ehime Maru ride smoother underneath, we need to keep the orientation of Rockwater into the most prominent sea state. So you may see it backing in, you may see it coming in sideways, but again, you'll need a micrometer to measure the speed. It's going to be very slow, intentionally so, and we expect that that could take as long as three to four days to make that transit, about 14.5 miles from the deep water site to the shallow water site.

Once we're at the shallow water site the Rockwater will disconnect and leave. She will come downtown, offload equipment, and then depart. We will, the following day move the 450, Crowley 450 dive barge over the top of Ehime Maru and we'll do some survey type dives on the second day and begin dives on the ship on the third day after it's set down.

So again getting an appreciation, three to four day transit time, two to three days on the shelf before we begin our internal diving operations. So a week after we have announced the lift before any serious operations begin.

Once we have begun the diving operations we expect to be diving for about 33 days. That is very dependent upon the internal condition of the ship, which is unknown at this time. But at this point anticipating that we will have access to those spaces, we will anticipate a 33-day dive plan.

I'd like to emphasize, as we have done at all the previous briefings, that this is an unprecedented evolution. There is still risk involved. I think we have reduced a considerable amount of the risk as we have seen in the lifting of the ship and the placement on the forward lifting strap. However, it's never going to be zero. So as a consequence, we should understand the potential for equipment failure or ship failure during this move is still there.

Further, after we get to the shallow water site, recognize that there may not be nine sets of remains on board as has been discussed in the past, so our expectations should be realistic. We will find some of those and probably not all of them.

I will emphasize that everything we do and have done from the very beginning has been predicated upon safety. We've had a tragic event here. We've lost some lives. And we cannot justify any further loss of life in this operation. So the people in charge on board Rockwater as well as the divers in port have not only the responsibility, but are charged with maintaining safety above all other criteria. That means if they have to set the ship down, if they have to stop the operation, if they have to put it on hold, or they have to remove people from the hull after diving has started, they have the authority and the responsibility to do so.

I think we have very high confidence in this operation and we expect to succeed. Expectations what they are, you also have to recognize there are some potential downfalls here.

A little bit later on today we should be providing some footage from the bow lift evolution itself, probably around 5:00 o'clock, between 4:00 and 5:00 o'clock this afternoon, I believe. That film footage is, unfortunately, largely obstructed by the amount of sediment that was disturbed in the move itself, but you can clearly see the lifting equipment as we began to take a strain on it, and we can see the bow completely up out of the silt, sitting high with the lifting gear under it. So there are some at least short clips of video there that would provide some additional information for you.

With that, that concludes my formal comments. We'll take some questions at this time if you have any.

Q: How many bodies do you expect to find?

A: I think we've said in the past that the number is probably in the five to seven range, based on where the folks were last seen.

Q: How high will the Ehime Maru be off the ocean bottom as they transport it into shallow water?

A: We expect it to be about 90 feet. As I explained this before, I guess probably not in this environment, but let me just give you a quick picture here.

Remember that we've got the Rockwater perpendicular to the Ehime Maru so what you're seeing here is these lines rigged over the side of Rockwater. If either one of these lines fails, the winch fails, or this lifting equipment fails on one side, then all the load is shifted to the Rockwater on one side and it will cause Rockwater to take a very significant roll. If that occurs, then obviously we have the potential for not only injury to personnel but equipment flying all over the place and some real nasty things could happen. In order to avoid that we need to keep the ship close to the bottom so if there's a failure then the Ehime Maru comes to rest on the bottom before it does serious damage topside.

So we will transit with probably about 90 feet under the Ehime Maru. As we come up the incline and the shelf into the shallow water site. So one of the ROVs will be preceding the ship. We have a regular convoy, if you will, of ships that will be escorting. Sumner will be in front. USNS Sumner is an oceanographic research vessel with a lot of the bathymetry equipment on board. They will be keeping a bottom profile, depth, and current information which they feed the Rockwater. As that incline, as it climbs, they will be passing that information to Rockwater, continually raising Ehime Maru to match the bottom profile.

Following along behind will be Salvor, USS Salvor, which will be used in one of several different roles. The primary role is to provide an ROV which does deep ocean search in the event that we have something come off of the Ehime Maru during the course of the transit. They'll also stand by for security and recovery operations if someone should go over the side. Rockwater would be unable to recover anyone that fell off of their own ship, so we have to provide that.

JDS Chihaya will also be out there in escort. She is currently out doing bridge surveys of the underwater area where the Ehime Maru had been located and she'll be following in as well. So there will be a small convoy of ships including the Coast Guard. Clean Island Council, the oil recovery vessel will be out there as well. So a fairly significant number of ships all providing a different piece of input to the movement operation.

Q: Have your resources been affected at all by the airstrikes and the current situation?

A: Not really. Let me explain that.

Most of this effort up to this point is contracted so Smit and Crowley, the prime contractors in this evolution, have continued to work. The Navy folks that are involved in this process are divers right now who have not been tasked for other missions so we do not expect to stop this mission at this point. It's unaffected.

Q: Is it possible that the relocation (inaudible) may [charge] Wednesday night, late Wednesday night? Will it be a continuous night and day operation once (inaudible)?

A: Generally speaking, it would be. We have some very specific criteria for crossing the shelf and into the shallow water sites that are specified in the environmental assessment. They include our ability to control any oil releases that might take place, for example. There will be an armada of oil skimmer equipment out there booming in place and so on. That is all designed through the EA to deal with that problem should it occur. Our expectation that it will occur is fairly low at this point, so we don't expect that to be a problem.

But to get to the heart of your question, the transit portion is kind of continuous. But once we reach the shelf we have to have a confluence of wind, current, sea state, and tide in order to cross that shelf and go into the shallow water site and that gives us the maximum protection under the environmental [potentials].

Q: Are there any more difficulties working through the night than there would be during the daylight hours?

A: Not really. As you probably know, we've been working 24 hours a day on this project since it started. The darkness at the depth that they're working at now is the same in the day time as it is at night. ROVs provide their own light, and this entire operation right up to the point where the ship is set down in shallow water will be an ROV evolution.

So the day light is really for us humans to be able to see the oil release if they occur in that last couple of miles.

Q: Admiral, have you ever had an operation where you dragged something across the ocean at this depth?

A: I would not characterize it as dragging it, because that implies contact.

Q: How would you characterize it?

A: I don't think we have any precedent for movement of a vessel of this size from that depth period. We've recovered much larger ships from much shallower depths, but the movement itself is very unique. I'm sure you realize that the Kursk for example was lifted earlier this week -- a much larger vessel from a much shallower depth. There is lots of experience in that environment -- very little in this environment.

Q: Without getting too technical, how do you keep the ship directly under the Rockwater? Assuming that's the way you move it.

A: Yes. Basically what it amounts to is at this depth these wires which are 4.5 inch diameter, 115 millimeter, so a two-part lift with very heavy cable acts almost as a solid rod. And so the things that affect the Ehime Maru at that depth are primarily the current and the speed of the Rockwater. That's why the speed will be greatly limited, because we do not want to encounter current which will cause Ehime Maru to depart from a straight path in.

As I mentioned, the orientation of the ship as it travels, when we back in with the Rockwater, this is the profile that you will see coming at you. So Rockwater would literally have to turn sideways and move towards the shore sideways in order for Ehime Maru to be aligned bow first in the transit. If the conditions call for that that's what they do. The Rockwater has the capability of moving in any direction up to several knots in speed, so if she has to move in sideways and that's the best configuration, that's what we'll do.

Q: Do you have any idea how long it will take from the deep water to shallow water?

A: About three to four days. Very slow. Probably, my best guess right now is between .2 and .5 knots. I don't think we will exceed .5 knots, a half a knot, half a nautical mile in an hour. Fourteen miles, you can figure it out, it takes a long time to transit as well as lifting. The lifting operation will be done fairly slowly. We can raise about one meter a minute. We have to come up 600 meters. So you can do some calculations there and figure out there's a number of hours involved in raising this thing. We will be incrementally raising it as we move, but if the incline becomes too steep, we'll have to stop to continue to raise it.

Q: (inaudible)

Q: Admiral, what is the greatest risk at this point? Is it equipment failure? Is it...

A: I would say probably the greatest risk, given weather. If we have adequate weather the greatest risk is probably equipment. We think the Ehime Maru is sound. We won't be 100 percent certain of that until we have an opportunity to survey the bottom with ROVs, but that will be the first step before we actually start moving. So assuming we verify that the structural conditions are sound, then primarily the risk is in the lifting equipment.

Q: What are the maximum sea states that you'll be able to do this in?

A: I was afraid you were going to ask that. This has more moving parts than anything you can imagine. There are six degrees of motion in Rockwater, six degrees of motion in Ehime Maru, and a computer program that ten years ago would have been too complicated to run.

We calculate dynamic amplification factors which tell us what the shock loading on this ship is. If you can imagine this thing is on a wire that is essentially solid. As the ship on the surface moves up and down and heaves, then it's raising and lowering the Ehime Maru against the resistance of water on the hull. If you jerk it, then you impart tremendous energy and the potential for breaking the ship exists. So the dynamic amplification factor is how we measure that.

The sea state by itself is not the only criteria. There's about 20 variables involved in this thing. So we could have a four foot sea state and not be able to move based on other criteria. But the bottom line is we think if we get down to in the six foot range with the right period of waves that we probably can lift the ship safely. That's not a rule of thumb, that's just kind of a statement. We have some empirical data now from our experience of lifting the bow of how it reacted in a sea state, and we have those calculations. So we have kind of validated what our expectations were.

Q: Is there any new plans or subsequent plans that would help in preventing additional mishaps during the transit period that have now come into play that wouldn't have been in play three or four weeks ago?

A: I don't think so. We have, as I mentioned, probably the most difficult challenge we face in lifting the ship successfully is in the wave height and the period. If we look at where waves come from this time of the season, we get sea swells from the south that have a longer period, and we get wind-driven seas that come primarily out of the east and in between the islands. So these two seas are running perpendicular to each other. Where they cross, they make a combined sea state which is what the ship sees in terms of motion.

For the first six miles or so of this transit the ship will be exposed to both of those sea states -- swells and seas driven by the wind. We will not move unless we have a window that will allow us to travel that first six miles. Once we pass that six mile point or approximately six mile point, we reach the lee that Oahu provides between the islands. That knocks down that wind-driven sea dramatically. So the condition continues to improve the closer into the shallow water site we get.

So our immediate criteria is we need to have a window of time that allows us to make that transit uninterrupted. We don't want to have to set the ship back down.

Q: At the same time we're fighting against perhaps greater impact the further we go...

A: Yes, there's no doubt. And every month... We've had this plotted out fairly accurately for a long time. We've known that the risks of weather, the later we get in the year are higher and higher. That doesn't mean you won't have a window, it just means that historically there's a longer period of time between windows.

So what we're looking at right now is if this opportunity presents itself then we're going to pick it up and go.

Q: How successful do you expect the Navy will be to take the Ehime Maru to shallow water, and (recover) five or seven more (crewmembers)? How successful and (inaudible)? Please provide the reason why.

A: When we initially set out to undertake this operation we concluded that based on our calculations we had about an 80 percent probability of success. We think that based on the experience of this past weekend that we're probably up in the ball park of 90 percent success rate right now.

Once we have the ship in shallow water I have no doubt that we will be able to enter the ship. We have the equipment to do that and to remove, recover the remains. So I have a very high confidence that once we're in the shallow water site we'll recover remains and personal effects.

There is a probability and a possibility that the inside of the ship is so severely disrupted that we would endanger the lives of our divers to go in there. In that eventuality we have a very small ROV, literally the size of a bread box, that will be used to go into those compartments to do the survey for us. And if we then have to go into those compartments we'll determine what the course is at that point.

So I think we have a very high probability of success once we're up there, and I would guess close to 90 percent probability of success in moving the ship.

Thank you all very much.

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