wheels 543 Posted December 10, 2013 Share Posted December 10, 2013 They recovered it from the seabed today. 123m down. It is currently on it's way to Picton, hanging 8M under the barge. They will crane it onto a ship to take it back to Wellington tonight to be there tomorrow morning. Link to post Share on other sites
smithy09 50 Posted December 10, 2013 Share Posted December 10, 2013 Hey Wheels. Who did the job do you know? Diving or ROV? Just interested! Link to post Share on other sites
wheels 543 Posted December 10, 2013 Author Share Posted December 10, 2013 Company is called Seaworks and they used an RV. The barge is a former US military tank carrier called Brandywine. They managed to get 4 strops around it. Pretty good going. The Strait had a light Southerly and about a 0.75m swell. Link to post Share on other sites
G Force 0 Posted December 10, 2013 Share Posted December 10, 2013 aren't you meant to be packing?........... good luck with the trip down. Link to post Share on other sites
smithy09 50 Posted December 10, 2013 Share Posted December 10, 2013 OK Yeah I found it. Damn small vessel to do that kind of work. Not even a crane on board!! Talk about a bare bones Kiwi operation. Got it done though. Good on them! Not easy to find something like that even with a decent position fix from the Ferry. Top job! Link to post Share on other sites
wheels 543 Posted December 10, 2013 Author Share Posted December 10, 2013 Another vessel (don't know if it was the same company) did a sonar sweep with a towed Sonar unit, to find it. It took a week or so before they located it. But yeah, with the Tidal Current, 125m depth and pitch black, it would still be a really difficult exercise. Link to post Share on other sites
grant 40 Posted December 10, 2013 Share Posted December 10, 2013 Another vessel (don't know if it was the same company) did a sonar sweep with a towed Sonar unit, to find it. It took a week or so before they located it. . ah,no Seaworks found it in a couple of hours, there was another company with different equipment had tried unsuccessfully before that, but when it was found it was quite quick. Done by lunchtime I believe Link to post Share on other sites
wheels 543 Posted December 10, 2013 Author Share Posted December 10, 2013 Oh sorry. I thought I had heard a news report a week or two ago that the Prop was found by the other company. Oh well, it's up which is the important part. Link to post Share on other sites
banaari 27 Posted December 10, 2013 Share Posted December 10, 2013 Any insight as to its mode of departure from the ship? Are we talking a snapped shaft, or what? Link to post Share on other sites
Mothership 6 Posted December 10, 2013 Share Posted December 10, 2013 Reading this, I just can't help but to be reminded of this: Link to post Share on other sites
Adrianp 120 Posted December 10, 2013 Share Posted December 10, 2013 I imagine its probably a 6 month lead time too though.... Link to post Share on other sites
rossd 16 Posted December 10, 2013 Share Posted December 10, 2013 That's good! Politics 101 Link to post Share on other sites
smithy09 50 Posted December 11, 2013 Share Posted December 11, 2013 The herald said a new 6 ton prop cost 200,000. I wonder how much the salvage cost, cant be too far away from that? I would have thought more than that. There's about NZ$50K in material alone.. Add manufacture, freight.... Link to post Share on other sites
wheels 543 Posted December 11, 2013 Author Share Posted December 11, 2013 Any insight as to its mode of departure from the ship? Are we talking a snapped shaft, or what? Yes the shaft snapped. Why no one knows just yet. There are suspicions. It has been taken to a workshop for inspection to see if they can work out why. Since the Ship was extended, there had been rumors that the Shafts vibrated. Who started that rumor I have no idea. But it could be a credible cause if there was a vibration. I imagine its probably a 6 month lead time too though....I have no idea on actual cost. Once again just what I heard, but I had been told it could take up to a year. You don't buy these off the shelf. Props of this size are designed for the requirements of the particular Vessel it is being built for. So a prop would actually have to be designed (they don't necessarily have the design kept somewhere on a file), foundry time would need to be booked and making a mold that size is no simple job. The pour is as normal as a pour this size would be, then time to cool off, then machining, then transport, then the Ship needs to get to a Dry Dock etc. Where as this way, the Aratere can take the prop with her to the dry dock. So hence why they were keen to get their hands on the original. The recovery cost wasn't really the main issue, all though there would be a ceiling limit I am sure. Link to post Share on other sites
too_tall 15 Posted December 11, 2013 Share Posted December 11, 2013 I suspect that finding out why this happened was a significant factor in the retrieval of the old prop too. Link to post Share on other sites
sow1ld 2 Posted December 11, 2013 Share Posted December 11, 2013 The main motivation for finding the prop is so that we can use it to help determine the cause of the failure. The cost of a new prop and shaft is relatively economical in the scheme of things. Vibration wise the terry is fairly normal (that you can feel) it will be interesting to see how it pans out. My suspicion is longer more weight more wetted surface area higher thrust Props and the fact the Terry gets flogged 6 crossings a day 7days a week it could just be as simple as fatigue Link to post Share on other sites
wheels 543 Posted December 11, 2013 Author Share Posted December 11, 2013 Surely shouldn't be anymore than any other Ship sailing the world 7days/wk. Also one reason why the shafts are supposed to be inspected every five years. It hasn't been five years already since it's upgrade has it?? Link to post Share on other sites
philstar 61 Posted December 11, 2013 Share Posted December 11, 2013 does it concern anybody that they've certified the ship to operate in one of the worlds roughest straits on one prop. and they have no idea why the other one broke I hope the wellington tugs are quick enough and powerful enough to save Aratere going on the rocks. Link to post Share on other sites
wheels 543 Posted December 11, 2013 Author Share Posted December 11, 2013 Yeah I did think that a strange thing to do. Link to post Share on other sites
sow1ld 2 Posted December 11, 2013 Share Posted December 11, 2013 Ten years for shaft inspections. They where checked when the ship was lengthened. It's all a bit odd. Stuff doing the cook strait run on one shaft! Link to post Share on other sites
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