Single Cruiser Posted March 17, 2014 #51 Share Posted March 17, 2014 (edited) Not going to disagree but the Breakaway has 6 very large fuel powered engines, which basically power everything electric. The entire propulsion system is electric, the ship needs three online to run at normal cruising speed. One engine is not going to slow the ship down, on a normal day only 4 engines are online, sometimes 5. It could very well be a bearing issue with one of the pods. My numbers may be off, I might be thinking of the Gem Breakaway has 4 engines. a 2 × 14V + 2 × 12V48/60CR Tier II engine configuration with 62,400 kW of installed MAN power Breakaway plus will have 5. The Breakaway Plus vessels will each be powered by five engines – 2 × 14V + 3 × 12V48/60CR Tier II types – capable of delivering 76,800 kW Edited March 17, 2014 by Single Cruiser Link to comment Share on other sites More sharing options...
chengkp75 Posted March 17, 2014 #52 Share Posted March 17, 2014 Not going to disagree but the Breakaway has 6 very large fuel powered engines, which basically power everything electric. The entire propulsion system is electric, the ship needs three online to run at normal cruising speed. One engine is not going to slow the ship down, on a normal day only 4 engines are online, sometimes 5. It could very well be a bearing issue with one of the pods. My numbers may be off, I might be thinking of the Gem Yep, you're thinking of Gem. Most NCL ships prior to Breakaway (not sure about Epic) had 5 or 6 engines. I was a little surprised to see that Breakaway had gone to the 4 larger engines. And see my math in the prior post about the power. Pretty well aware how a diesel electric plant works, and my math shows that with a 12 cylinder engine out of service, she could only give about 80% of the pods requirements, and with a 14 cylinder out, that would drop even more. I also stated earlier that with 5 or 6 engines that loss of one would not preclude the ship maintaining full propulsion power, but when one engine accounts for 25% of capacity, it really hurts to have it out of service. Link to comment Share on other sites More sharing options...
smeyer418 Posted March 17, 2014 #53 Share Posted March 17, 2014 Yep, you're thinking of Gem. Most NCL ships prior to Breakaway (not sure about Epic) had 5 or 6 engines. I was a little surprised to see that Breakaway had gone to the 4 larger engines. And see my math in the prior post about the power. Pretty well aware how a diesel electric plant works, and my math shows that with a 12 cylinder engine out of service, she could only give about 80% of the pods requirements, and with a 14 cylinder out, that would drop even more. I also stated earlier that with 5 or 6 engines that loss of one would not preclude the ship maintaining full propulsion power, but when one engine accounts for 25% of capacity, it really hurts to have it out of service. Epic has 6 http://en.wikipedia.org/wiki/Norwegian_Epic interesting thread! Link to comment Share on other sites More sharing options...
Rare Laszlo Posted March 18, 2014 #54 Share Posted March 18, 2014 Yep, you're thinking of Gem. Most NCL ships prior to Breakaway (not sure about Epic) had 5 or 6 engines. I was a little surprised to see that Breakaway had gone to the 4 larger engines. And see my math in the prior post about the power. Pretty well aware how a diesel electric plant works, and my math shows that with a 12 cylinder engine out of service, she could only give about 80% of the pods requirements, and with a 14 cylinder out, that would drop even more. I also stated earlier that with 5 or 6 engines that loss of one would not preclude the ship maintaining full propulsion power, but when one engine accounts for 25% of capacity, it really hurts to have it out of service. Thanks for the info, I stand corrected Link to comment Share on other sites More sharing options...
Paraveina Posted March 18, 2014 #55 Share Posted March 18, 2014 I was at the Officer Q&A on Saturday and the Chief Engineer was supposed to be there, but he was not present. They did, however, talk about the 4 DGs (plus the emergency one), so 4 + 1. I wonder what the problem was? Also, did anyone else on this past sailing notice the loop we did between GSC and Nassau? I saw it on the Navigation channel the morning we got to Nassau. Link to comment Share on other sites More sharing options...
time2cruise1 Posted March 18, 2014 #56 Share Posted March 18, 2014 I was at the Officer Q&A on Saturday and the Chief Engineer was supposed to be there, but he was not present. They did, however, talk about the 4 DGs (plus the emergency one), so 4 + 1. I wonder what the problem was? Also, did anyone else on this past sailing notice the loop we did between GSC and Nassau? I saw it on the Navigation channel the morning we got to Nassau. If you did not do a loop the ship would have been in Nassau in time for a late dinner :D Sent from my iPad using Tapatalk - Jim Link to comment Share on other sites More sharing options...
Paraveina Posted March 18, 2014 #57 Share Posted March 18, 2014 If you did not do a loop the ship would have been in Nassau in time for a late dinner :D Sent from my iPad using Tapatalk - Jim Why wouldn't they just go slowly instead? Doesn't looping waste diesel? Link to comment Share on other sites More sharing options...
Rare LMaxwell Posted March 18, 2014 #58 Share Posted March 18, 2014 They did, however, talk about the 4 DGs (plus the emergency one), so 4 + 1. It's possible the 5th generator is used as a backup for hotel power only and not for propulsion? I really don't know. I do however find this thread fascinating and enjoy learning the technical aspects of ships. Link to comment Share on other sites More sharing options...
chengkp75 Posted March 18, 2014 #59 Share Posted March 18, 2014 Why wouldn't they just go slowly instead? Doesn't looping waste diesel? Not necessarily. It depends on how much time was killed doing the loop, and what the reason was. You don't want to start a passage going too slow, saying that is the speed we need to make our timed arrival, and then find out the Gulf Stream was stronger today than the previous week, and you're going to be late, so then you have to speed up to make the arrival time. It also depends, again, on the engine configuration of the ship. It may save fuel to run three engines at near full load for the passage, and then kill 15 minutes doing a loop, rather than running 3 engines at a much lower load to go slower (provided you could not run slow enough to drop to two engines). A lot of that depends on weather conditions (wind, seas, current, tide). Link to comment Share on other sites More sharing options...
chengkp75 Posted March 18, 2014 #60 Share Posted March 18, 2014 It's possible the 5th generator is used as a backup for hotel power only and not for propulsion? I really don't know. I do however find this thread fascinating and enjoy learning the technical aspects of ships. The "5th generator" is the emergency generator. It is designed only to be used when none of the main generators are available. It's primary function is to provide power to the equipment required to get everyone off the ship in an abandon ship situation. These days, given Carnival's problems, it has expanded to cover more hotel functions, but is still only used for emergencies. Further, the main generators generate 10,000volt power (think of the high tension lines you see on land), which is used directly by the large consumers onboard (azipods, thrusters, air conditioning compressors), and also stepped down to 480volt power (think factory or commercial buildings on land) for most all other major consumers onboard (engine room motors, fans, steering) and then down to 220volt and 110volt for hotel appliances and outlets. The emergency generator only provides 480volt power, as it is not designed to provide power to the propulsion. Link to comment Share on other sites More sharing options...
Rare Laszlo Posted March 18, 2014 #61 Share Posted March 18, 2014 (edited) The "5th generator" is the emergency generator. It is designed only to be used when none of the main generators are available. It's primary function is to provide power to the equipment required to get everyone off the ship in an abandon ship situation. These days, given Carnival's problems, it has expanded to cover more hotel functions, but is still only used for emergencies. Further, the main generators generate 10,000volt power (think of the high tension lines you see on land), which is used directly by the large consumers onboard (azipods, thrusters, air conditioning compressors), and also stepped down to 480volt power (think factory or commercial buildings on land) for most all other major consumers onboard (engine room motors, fans, steering) and then down to 220volt and 110volt for hotel appliances and outlets. The emergency generator only provides 480volt power, as it is not designed to provide power to the propulsion. I want you with me if I'm ever on a sinking ship! I'll still have me EPIRB with me Edited March 18, 2014 by Laszlo Link to comment Share on other sites More sharing options...
Paraveina Posted March 18, 2014 #62 Share Posted March 18, 2014 It may save fuel to run three engines at near full load for the passage, and then kill 15 minutes doing a loop, rather than running 3 engines at a much lower load to go slower (provided you could not run slow enough to drop to two engines). A lot of that depends on weather conditions (wind, seas, current, tide). That makes sense. I didn't think about two engines potentially not being enough. Link to comment Share on other sites More sharing options...
chengkp75 Posted March 18, 2014 #63 Share Posted March 18, 2014 I was at the Officer Q&A on Saturday and the Chief Engineer was supposed to be there, but he was not present. They did, however, talk about the 4 DGs (plus the emergency one), so 4 + 1.I wonder what the problem was? Also, did anyone else on this past sailing notice the loop we did between GSC and Nassau? I saw it on the Navigation channel the morning we got to Nassau. Ships with 5 or 6 diesels tend to have one down for maintenance at any time. Given Breakaway's schedule, this requires close coordination between the maintenance intervals and the periods of the weekly itinerary where only 3 engines are required. Ships do not stock a spare for every part on a 18,000 horsepower engine, so sometimes even a minor failure could cause the engine to be out of service until a part arrives. It could also be an automation problem, it really could be nearly anything. It could also be that the problem is being worked on from the very beginning, but it is a problem that requires some time to complete, and the engineers will have it back up and running in the next couple of days. Link to comment Share on other sites More sharing options...
chengkp75 Posted March 18, 2014 #64 Share Posted March 18, 2014 with respect. Running the ship at full speed is not good for them and is heck on gas mileage. First to get full speed you have to use much more fuel than running at 75% of speed. Running one engine less also saves fuel and allows you when you have a problem to make the same time. Ask NCL and they will tell you that running the Dawn at almost full speed for the time it did when it was traveling from NY to Florida on this run wasn't good for it... Again, you are mistaking a diesel electric power plant with your car. Yes, the fuel required to move a ship increases roughly with the square of the ship's speed. But fuel consumption has nothing to do with wear and tear on either a diesel generator or an electric azipod motor. Again, I will rely on my experience and say that the "specific fuel consumption" (the grams of fuel burned per horsepower hour) is least at 75-85% of rated capacity. So you are at maximum efficiency for the diesel at this load. So the optimum fuel efficiency for the ship is to operate the least number of diesels at the highest load. What I am saying is that there is a fuel efficiency for the engines, and one for the ship, and the most efficient point is not the same for both, and the fuel efficiency of the engines has nothing to do with ship's speed. But once again, fuel efficiency has nothing to do with wear and tear. The engines are designed to run at 100% load for 12,000 hours without major servicing. Running at low loads on diesel engines burning heavy fuel oil can in fact cause more wear on the engine, as the exhaust temperature is not high enough to keep the sulfur dioxide and water vapor in the exhaust from forming sulfuric acid and causing corrosion to piston rings, cylinder liners, and exhaust valves. Now, running more engines just to make a full speed run, will increase the total number of running hours per year, and mean the overhauls come quicker, but that is a cost analysis, not a maintenance issue. I have operated and maintained large diesel power generating and propulsion plants onboard ships for nearly 40 years. Link to comment Share on other sites More sharing options...
meatball_nyc Posted March 18, 2014 #65 Share Posted March 18, 2014 Incredible info. I hope everyone has been taking notes. There is going to be a quiz on Friday. I'm kidding !!! Thank you chengkp for so patiently explaining the details of the ship's engines. Very interesting stuff. Let's all hope that the problems are fixed once in PC. Happy Sailing! ~Robin Norwegian Breakaway July 2014 Carnival Miracle 2010 Carnival Legend 2006 Link to comment Share on other sites More sharing options...
nycmode Posted March 18, 2014 #66 Share Posted March 18, 2014 I hope we hear from the folks when they reach Port Canaveral later this afternoon about what's been going on Link to comment Share on other sites More sharing options...
time2cruise1 Posted March 18, 2014 #67 Share Posted March 18, 2014 (edited) 2 minutes ago approaching PC at 21.1 knots. Problems may be resolved Sent from my iPad using Tapatalk - Jim Edited March 18, 2014 by time2cruise1 Link to comment Share on other sites More sharing options...
nycmode Posted March 18, 2014 #68 Share Posted March 18, 2014 2 minutes ago approaching PC at 21.1 knots. Problems may be resolved Sent from my iPad using Tapatalk - Jim Hopefully! Their ETA was 3pm ET - maybe ahead of sked after all. Link to comment Share on other sites More sharing options...
meatball_nyc Posted March 18, 2014 #69 Share Posted March 18, 2014 Not so late after all. Hope all is well. I've been watching her webcam all day yesterday and this morning. Bad weather almost the whole way. ~Robin Norwegian Breakaway July 2014 Carnival Miracle 2010 Carnival Legend 2006 Link to comment Share on other sites More sharing options...
babybubba Posted March 18, 2014 #70 Share Posted March 18, 2014 I'm looking at the Breakaway bridge cam and I don't see any sign of land so I'm guessing they're still running at a slower speed. I hope they get it straightened out. We were on the NCL Dawn years ago and one of the azipods stopped working. Our day at GSC was canceled so we could limp back to NYC with one Azipod. The ship was seriously listing to one side. A lot of passengers were furious! It was a little scary, I thought they were going to call mutiny. :eek: Link to comment Share on other sites More sharing options...
time2cruise1 Posted March 18, 2014 #71 Share Posted March 18, 2014 I'm looking at the Breakaway bridge cam and I don't see any sign of land so I'm guessing they're still running at a slower speed. I hope they get it straightened out. We were on the NCL Dawn years ago and one of the azipods stopped working. Our day at GSC was canceled so we could limp back to NYC with one Azipod. The ship was seriously listing to one side. A lot of passengers were furious! It was a little scary, I thought they were going to call mutiny. :eek: Slower speed ? Currently 21.4 knots about 1 hour out from PC. Sent from my iPad using Tapatalk - Jim Link to comment Share on other sites More sharing options...
meatball_nyc Posted March 18, 2014 #72 Share Posted March 18, 2014 See land now. ~Robin Norwegian Breakaway July 2014 Carnival Miracle 2010 Carnival Legend 2006 Link to comment Share on other sites More sharing options...
meatball_nyc Posted March 18, 2014 #73 Share Posted March 18, 2014 (edited) I see her on the PC webcam She just sailed by, but now out of shot. ~Robin Norwegian Breakaway July 2014 Carnival Miracle 2010 Carnival Legend 2006 Edited March 18, 2014 by meatball_nyc Link to comment Share on other sites More sharing options...
EBONI325 Posted March 18, 2014 #74 Share Posted March 18, 2014 Not so late after all. Hope all is well. I've been watching her webcam all day yesterday and this morning. Bad weather almost the whole way. ~Robin Norwegian Breakaway July 2014 Carnival Miracle 2010 Carnival Legend 2006 Can you give me the link for the webcam? Thank you Link to comment Share on other sites More sharing options...
meatball_nyc Posted March 18, 2014 #75 Share Posted March 18, 2014 http://www.cruisinme.com Select NCL then Breakaway. ~Robin Norwegian Breakaway July 2014 Carnival Miracle 2010 Carnival Legend 2006 Link to comment Share on other sites More sharing options...
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