Rare BecciBoo Posted April 11, 2018 #51 Share Posted April 11, 2018 Wow another one! This line needs to get qualified masters! Link to comment Share on other sites More sharing options...
Rare xpcdoojk Posted April 11, 2018 #52 Share Posted April 11, 2018 Would imagine that if the dock were closed they might tender to shore. I doubt that they will immediately quit calling on that port. JC Link to comment Share on other sites More sharing options...
Rare broberts Posted April 11, 2018 #53 Share Posted April 11, 2018 Wow another one! This line needs to get qualified masters! Most would refrain from such a judgement until all significant facts surrounding the collision were known. Link to comment Share on other sites More sharing options...
LS6Caddy Posted April 11, 2018 Author #54 Share Posted April 11, 2018 Would imagine that if the dock were closed they might tender to shore. I doubt that they will immediately quit calling on that port. JC To my knowledge Oasis class will not tender to parts...due to the number of passengers on the ship that seems like a daunting task. Link to comment Share on other sites More sharing options...
Rare xpcdoojk Posted April 11, 2018 #55 Share Posted April 11, 2018 To my knowledge Oasis class will not tender to parts...due to the number of passengers on the ship that seems like a daunting task. I avoid the Caribbean in general and the Western Caribbean even more so. But do any Oasis class ships go to Honduras? JC Link to comment Share on other sites More sharing options...
nealstuber Posted April 11, 2018 #56 Share Posted April 11, 2018 I avoid the Caribbean in general and the Western Caribbean even more so. But do any Oasis class ships go to Honduras? JC I don’t think so, but Acromonia just did some serious dredging so maybe they can in the future. Sent from my iPhone using Forums Link to comment Share on other sites More sharing options...
Rare 01Sweetpea Posted April 11, 2018 #57 Share Posted April 11, 2018 We are on the 4/22 Liberty OTS sailing and are suppose to be in Roatan in 2 weeks. Waiting to see what happens and IF RCI cancels this port. Link to comment Share on other sites More sharing options...
ace1zoe2 Posted April 11, 2018 #58 Share Posted April 11, 2018 I avoid the Caribbean in general and the Western Caribbean even more so. But do any Oasis class ships go to Honduras? JC We’re on Allure in October & we have a port stop in Roatan. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
BEENSAILING Posted April 11, 2018 #59 Share Posted April 11, 2018 because of MSC both a Royal and Celebrity ship cancelled port call in Roatan. Link to comment Share on other sites More sharing options...
BEENSAILING Posted April 11, 2018 #60 Share Posted April 11, 2018 I avoid the Caribbean in general and the Western Caribbean even more so. But do any Oasis class ships go to Honduras? JC In September 2015 we were on the Anthem. 12 nights western carrib from Bayonne including Roatan. I am glad we were there. best zip line ever! Link to comment Share on other sites More sharing options...
SailorJeff66 Posted April 12, 2018 #61 Share Posted April 12, 2018 Where am I? Working. Up all night taking bunkers, now up all night leaving Philadelphia. Had to sleep sometime, I do have a job that pays the bills, unlike answering questions on CC! :D As for the question about thrusters, the problem with thrusters is that being in a tunnel across the hull, any forward motion by the ship creates water flow past the thruster tunnel mouth, and this water motion reduces the amount of water the thruster can drag into the tunnel to force out the other side to produce thrust. When a ship is going above about 3 knots, thruster efficiency reaches about 10%. Pretty fair assesments Cheng. Also, I'm assuming the Azipods are quite like the APU on some of our Navy ships. Running them nose to nose, tail to tail, or directly tail to nose creates a lot of cavitation but the thrust is negligible. if they had the pods both at 090r, in an attempt to swing the stern over, the loss of thrust would likely reduce any attempt to reduce headway. Just a Dumb FC though....;p Link to comment Share on other sites More sharing options...
AmazedByCruising Posted April 12, 2018 #62 Share Posted April 12, 2018 Where am I? Working. Up all night taking bunkers, now up all night leaving Philadelphia. Had to sleep sometime, I do have a job that pays the bills, unlike answering questions on CC! :D A book, Chief! Please find a publisher that compiles your posts into a book, explaining all from the light and the whistle in a restaurant, to inspections and the wrong screws, how ships are insured, Noro, electricity on a ship, the difference betweens eggs and egg product, to death people getting fined for not enjoying the full trip. I'm not the only one who's browser suggests finding posts by user 945200 when I type C in the browser bar. Millions of people get on a ship each year, more than 1% wants to know more. If it was't for CC the only real info I'd have were books with funny stories by captains (and their wifes), an art auctioneer who claims he wasn't allowed to eat, and a musician who stumbled upon a ship. Link to comment Share on other sites More sharing options...
chengkp75 Posted April 12, 2018 #63 Share Posted April 12, 2018 Pretty fair assesments Cheng. Also, I'm assuming the Azipods are quite like the APU on some of our Navy ships. Running them nose to nose, tail to tail, or directly tail to nose creates a lot of cavitation but the thrust is negligible. if they had the pods both at 090r, in an attempt to swing the stern over, the loss of thrust would likely reduce any attempt to reduce headway. Just a Dumb FC though....;p Mainly I'm speaking of tunnel thrusters, like the ship has at the bow. People have reported that the thrusters were seen going quite hard, and someone asked whether thrusters couldn't have turned the bow. Azipods are a different story, however, since the propellers are not in tunnels or kort nozzles, the propellers don't lose thrust at high speed (or the ship wouldn't move). Those Navy APU's are thrusters with kort nozzles, which is like a real short tunnel. Kort nozzles around propellers are designed to provide static thrust (like a tug boat pushing against a ship), rather than propulsive power. One advantage of the azipods is that they can be swung so that they are giving both lateral thrust, and reverse thrust to slow the ship. My hypothesis is that the ship was coming in perpendicular to the dock due to channel configuration, it was supposed to stop, then swing 90*, and then ease laterally to the dock. I'm suspecting that the pods were ordered to reverse, which unlike most propellers doesn't turn the propeller the other way, the whole pod rotates so the propeller is now facing aft, but they failed to rotate, so there was no braking force to stop the ship's motion towards the dock. Link to comment Share on other sites More sharing options...
SailorJeff66 Posted April 12, 2018 #64 Share Posted April 12, 2018 Noted. Also didn't appear to be a lot of wash from the stern indicating a hard backing bell. I'm a lot more versed on prop and rudder propulsion as opposed to pods, but if they were in extremis and the rotation of the pods operating properly, I would expect to see a good bit of astern wash. Link to comment Share on other sites More sharing options...
Junkhouse Posted April 12, 2018 #65 Share Posted April 12, 2018 We are on LOS and it did effect us. Missed port because of this issue. However had s great sea day but had to detour to Cozumel for medical emergency. Pray that the individual is slright but will be getting to Costa Maya several hours late. At least got to go to Cozumel twice even if the first time we couldn't get off. Hope an MSC boat doesn't get to the port before we make it there! Link to comment Share on other sites More sharing options...
chengkp75 Posted April 12, 2018 #66 Share Posted April 12, 2018 Noted. Also didn't appear to be a lot of wash from the stern indicating a hard backing bell. I'm a lot more versed on prop and rudder propulsion as opposed to pods, but if they were in extremis and the rotation of the pods operating properly, I would expect to see a good bit of astern wash. Yes, I'm operating from the handicap of not being able to view video, but you're right, even not in extremis, there should have been astern thrust to stop the ship, which should have been visible. That's why I believe the pods weren't operating properly, and why they decided to drop one hook to slow things down. It must have been a glitch, or a short term failure of the azimuthing circuit since the ship is underway and steering normally. And since it affected both pods, apparently (again can't see evidence one way or the other), I would suspect a problem with the bridge control circuit over a concurrent failure of both pod's azimuthing systems. It could even be as simple as a failure to properly transfer controls from the telegraph/helm combination used at sea, to the joystick control used while docking. Link to comment Share on other sites More sharing options...
BillB48 Posted April 12, 2018 #67 Share Posted April 12, 2018 Hopefully you can see some screen shots, Chief. In the first shot I would estimate she was doing at least 5 knots, really coming in hot. Speed did not appreciably reduce until she made contact just below the anchor pocket. Apparently she T boned the walk way to what would have been the forward mooring dolphin. Can't tell in the last shot if she was opened up just under the anchor pocket. Link to comment Share on other sites More sharing options...
BillB48 Posted April 12, 2018 #68 Share Posted April 12, 2018 This one got dropped during the upload, shows the wash... I don't know if she has a shaft or pods. Link to comment Share on other sites More sharing options...
chengkp75 Posted April 12, 2018 #69 Share Posted April 12, 2018 Can't see them right now, but the system is so squirrely that they may show up in an hour or two if I leave the page on. According to wiki (I know, I know), she has two pods. A poster on the MSC thread says that a hole was welded, but I don't have any confirmation. From what I've seen, I don't believe the small black oblong under the stainless hawse cladding is a hole. It just doesn't have the right shape for a tear from a stationary object. Can you estimate how far off she is when you first see the ship, and it is doing 5 knots or so? Without any reversing, speed won't come off very much in under a half mile to a mile. This is another disadvantage of pods, steering and propulsion are common, so a failure of control to one most likely means a failure of control to both. With a prop and rudder ship, even if you can't reverse the propellers, you can "wig wag" the big barn doors under the stern to both swing the ship and to slow it down. Link to comment Share on other sites More sharing options...
Clarea Posted April 12, 2018 #70 Share Posted April 12, 2018 Can't see them right now, but the system is so squirrely that they may show up in an hour or two if I leave the page on. According to wiki (I know, I know), she has two pods. A poster on the MSC thread says that a hole was welded, but I don't have any confirmation. From what I've seen, I don't believe the small black oblong under the stainless hawse cladding is a hole. It just doesn't have the right shape for a tear from a stationary object. Can you estimate how far off she is when you first see the ship, and it is doing 5 knots or so? Without any reversing, speed won't come off very much in under a half mile to a mile. This is another disadvantage of pods, steering and propulsion are common, so a failure of control to one most likely means a failure of control to both. With a prop and rudder ship, even if you can't reverse the propellers, you can "wig wag" the big barn doors under the stern to both swing the ship and to slow it down. So for ships like Royal's Voyager/Freedom class, which I believe have two rotatable azipods and one fixed pod on the centerline, can the rotation of the prop on fixed pod be reversed to provide braking, or must they rotate the two outer pods 180 degrees to provide braking? Link to comment Share on other sites More sharing options...
chengkp75 Posted April 12, 2018 #71 Share Posted April 12, 2018 So for ships like Royal's Voyager/Freedom class, which I believe have two rotatable azipods and one fixed pod on the centerline, can the rotation of the prop on fixed pod be reversed to provide braking, or must they rotate the two outer pods 180 degrees to provide braking? The fixipod can be reversed (rotation), but given its position on the centerline, and the pod behind the propeller, it has much less efficiency than the rotated pods. It is better than nothing, but less than the outer pods. Link to comment Share on other sites More sharing options...
Clarea Posted April 12, 2018 #72 Share Posted April 12, 2018 The fixipod can be reversed (rotation), but given its position on the centerline, and the pod behind the propeller, it has much less efficiency than the rotated pods. It is better than nothing, but less than the outer pods. Thanks. I know it's probably too early to conjecture on the cause of the accident, but I thought (probably learned from one of your posts) that a ship needed two functional azipods to approach a port, otherwise there have to be tugs involved. Maybe this is a US Coast Guard regulation? Link to comment Share on other sites More sharing options...
Biker19 Posted April 12, 2018 #73 Share Posted April 12, 2018 Can you estimate how far off she is when you first see the ship, and it is doing 5 knots or so? Less than 100 yards. Link to comment Share on other sites More sharing options...
chengkp75 Posted April 12, 2018 #74 Share Posted April 12, 2018 Thanks. I know it's probably too early to conjecture on the cause of the accident, but I thought (probably learned from one of your posts) that a ship needed two functional azipods to approach a port, otherwise there have to be tugs involved. Maybe this is a US Coast Guard regulation? This is a USCG requirement for entering US ports, other countries have their own regulations. Another disadvantage of pods. With rudders, you have two sets of hydraulic motors on each rudder (twin rudders for twin propellers), so actually 4 means of steering. You can lose two sets and still meet the USCG requirement. You can also lose the port propulsion, say, and the starboard rudder's two steering motors, and still meet the USCG requirement, since redundant propulsion is not required, and the port rudder will still steer the ship with only the starboard propeller turning. With pods, which have two systems for azimuthing (or steering) each, if you lose the propulsion of that pod, the two steering systems are out as well. And because the redundant steering systems on each pod are trumped by the propulsion, having only one pod, even with two steering systems on that pod, doesn't meet the requirement for redundant systems. Link to comment Share on other sites More sharing options...
chengkp75 Posted April 12, 2018 #75 Share Posted April 12, 2018 Less than 100 yards. If so, and she is still doing 5 knots, there isn't anything, including full reverse power on the azipods, that would stop her in time. Link to comment Share on other sites More sharing options...
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