Norweign Ship Evacuation

[chengkp75]

2 minutes ago, Hawaiidan said:

BUT..... her shafts were reduction geared then to the electric motor powered by the diesel....   The recip steam engines were  through a reduction gear but no  electric.   If you saw Titanic  the cheif engineer has to stop the engine and put in reverse jacking gear to back down.....   

Ya Azipod...  So viking cheaped out  and went  prop shafts ?    Costs less...  but Viking is building a ton of new ships... cutting costs as much as possible...  Wonder what else the cheeped out on.

Makes you wonder.

No, the shafts on the Sky are direct connected to the propulsion motors, no gearing.  Who cares about steam reciprocating engines, they were out after the Liberty ships of WWII.  And virtually every cargo ship afloat today has their diesel engine directly connected, without gearing, to the propeller shaft.  As for the cost of azipods versus shafted propellers, you have that completely backward.  The major draw for azipods is that the capital cost to build an azipod, with its associated ancillary equipment is less than a propulsion motor, shaft, bearings, propeller, rudder, and two steering motors for each rudder.  The Promas system used by the Viking ships costs even more than a simple conventional shafted propeller and rudder, as there is the hydrodynamic fairing between the rudder and propeller.  This system improves propeller efficiency, and gets this system near the 10% improvement in efficiency from azipods.  

[chengkp75]

2 minutes ago, Hawaiidan said:

 

No..... I am not a naval architect...  However  direct shaft is cheaper I was told   has a lot of parasitic friction in the  main brgs   that the Azipod dosent. but cost more.    Main shaft screws are prone to a lot of problems because of all the extra junk..... old school junk       I think the resemblance between a Oceania and  Viking ship is scary close....    and Viking  was trying to look like them.... but  from what I have seen, cut a lot of stuff and made her  Nordic  minimalist.   in my opinion

By the way the Fletcher has 60K SHp  total....   Birthday disease must have kicked in.

Ah, going all the way back to the Fletchers, that's why I didn't recognize the horsepower, as the gas turbine codag destroyers and such have only 20-30k horsepower electric motors.  And by the way, the Fletcher didn't have electric motors, but steam turbines, which is totally different, but far more close to the SS United States, which was obviously far more efficient, since it pushed 22 times the weight for twice the power.

 

So, in your opinion, why do 98% of the world's shipping, including some of the largest ships ever built, and using the largest power plants afloat still use the "old school junk" that I'm not sure what you are referring to.  Guess what, azipods have radial bearings and thrust bearings just like shafted propellers.  The efficiency that azipods bring to the table is due to the propeller leading the shaft pod, not trailing it like a shafted propeller.  I have worked on ships with shafted propellers for over 40 years, and never had a problem with the shafting.  We've had stern seal problems, but guess what, an azipod has a stern seal as well, and it is just as vulnerable to damage as any stern seal.

[Fouremco]

1 hour ago, chengkp75 said:

Please link me to where it was stated that the Norwegian authorities advised the Captain not to sail, I haven't seen that, and would be very surprised if it was released to the public if factual.

Here is one of many media reports making headlines today: https://www.telegraph.co.uk/news/2019/03/25/norwegian-police-investigate-viking-sky-cruise-ship-set-sail/ 

[chengkp75]

4 minutes ago, Fouremco said:

Here is one of many media reports making headlines today: https://www.telegraph.co.uk/news/2019/03/25/norwegian-police-investigate-viking-sky-cruise-ship-set-sail/ 

Okay, that says that the AIBN thinks the risk was too high, now, but what was claimed was that the Captain was "warned" by "Norwegian officials" not to sail.  Here is an article that quotes a person from the Norwegian Coastal Administration, and a Pilot Master:

 

https://www.newsinenglish.no/2019/03/25/investigation-begins-into-cruise-drama/

 

who said “There was nothing to indicate that this ship couldn’t sail and carry out its voyage plan in a safe and secure manner.”

[Tennessee Titan]

2 hours ago, Copper10-8 said:

 

You mean "Azipod" propulsion and Viking Sky does not have pods; she has four 7,250 KW diesel-electric engines with two shafts driving two six-bladed fixed-pitch propellers 

 

 

 

 

Just info. Princess ships do NOT have azipods.....

[chengkp75]

1 hour ago, Hawaiidan said:

 

ABC  news said an inquiry is opened and that the ship left against advice.    Thats all I know

 

Fletcher class DD    steam/ electric/ type D boiler.     The engines GE

electric said 60,000....  in main control. by the throttle board....   I forget how many turns we could do. 

There is a hull speed 2x square rt of the water line that determines top speed.    The Fletcher  was the finest total warship in  the navy,   383 ft  as I recall.    I have seen her do 34 kts,  Arliegh Burke   Sp   was called 31 Kt Burke  as he sailed  his DES/RON 8  Black cats,  If I recall     I was a navigator back in 64/68     USS Trathen DD530

Missed this in previous responses, but "hull speed" is not "top speed".  Hull speed is a calculation based on water line length, and represents the most efficient speed, not the top speed.  The fact that the Fletchers needed 120k horsepower to push that light and short of a ship to 34 knots means they were pushing far and away above hull speed.  Even the SS US was pushing over her hull speed, as similar length cruise ships today push far heavier ships at comparable speeds (think QM2) with far less horsepower.

[Fouremco]

7 minutes ago, chengkp75 said:

Okay, that says that the AIBN thinks the risk was too high, now, but what was claimed was that the Captain was "warned" by "Norwegian officials" not to sail.  Here is an article that quotes a person from the Norwegian Coastal Administration, and a Pilot Master:

 

https://www.newsinenglish.no/2019/03/25/investigation-begins-into-cruise-drama/

 

who said “There was nothing to indicate that this ship couldn’t sail and carry out its voyage plan in a safe and secure manner.”

I'm sure that there are many differing opinions on the appropriateness of the cruise ship heading out when most other vessels decided to remain in port. The investigation will presumably address all of the facts and opinions. 

[chengkp75]

3 minutes ago, Fouremco said:

I'm sure that there are many differing opinions on the appropriateness of the cruise ship heading out when most other vessels decided to remain in port. The investigation will presumably address all of the facts and opinions. 

The investigation will address all of the facts, but not the opinions, opinions are not relevant to an investigation.  And I can't say for sure that "most other vessels" decided to remain in port, since the only two that I've heard made this decision were the two Hurtigruten ships.  A screen shot from marinetraffic on another thread shows a tanker and a cargo ship in the vicinity of the Sky at the time she lost power, so not all ships decided to stay in port or divert around the storm.

[Fouremco]

5 minutes ago, chengkp75 said:

I can't say for sure that "most other vessels" decided to remain in port, since the only two that I've heard made this decision were the two Hurtigruten ships. 

Just quoting from the same article that you cited and quoted from.

 

I'd suggest that opinions are highly relevant, because the captain's judgement is being questioned. Yes, facts are critical in establishing the conditions at the time, but it is his decision that it was safe to proceed given the conditions that lies at the heart of the investigation. 

[sevenseasnomad]

I was thankful to hear that everyone is safe, but what a harrowing experience, one none of these passengers will likely forget.

[rkacruiser]

Surely glad that Viking Sky safely made port and am thankful that there was no loss of life.  Surely hope that those injured will recover quickly.

I expect that all guests who have been affected by this event will be financially made whole by Viking Ocean Cruises and/or their own travel insurance.  They have endured enough "trauma" without having to endure further bureaucratic hoops.

 

However, it's disappointing that the "finger pointing" has begun. 

 
 

[the2ofus]

I learned yesterday that four people from our small city were on the ship and reported they were glad to be safe on land once more in Molde according to a report in our local paper.  They wore life vests throughout, said the temp in the ship was into the forties.  They are related to a friend here so I may hear more about their experience when they return home.

[Copper10-8]

6 hours ago, Tennessee Titan said:

Just info. Princess ships do NOT have azipods.....

 

Got it and thanks however, I was responding to a poster's theory that Viking Ocean Cruises has been/is "cheapening" the design and construction of their ships, incl. Viking Sky, that was blown out of the water (the theory, not Viking Sky) by our resident nautical engineering expert, Chengkp75

[SeaDog-46]

Just an aside - coastal cargo ship Hagland Captain - that was also in trouble is now safely alongside in a small port north of Molde.

Off tonight to join Westerdam in Yokohama on Sunday for 28 days.

Over & out - John

[RuthC]

9 hours ago, the2ofus said:

I learned yesterday that four people from our small city were on the ship and reported they were glad to be safe on land once more in Molde according to a report in our local paper.  They wore life vests throughout, said the temp in the ship was into the forties.  They are related to a friend here so I may hear more about their experience when they return home.

I, at least, would be interested in hearing their tales, should you care to post about them. First-hand accounts are always good.

[kazu]

47 minutes ago, RuthC said:

I, at least, would be interested in hearing their tales, should you care to post about them. First-hand accounts are always good.

 

Ditto. 😄 

[rafinmd]

One thing I've frequently seen people post is "In an emergency I want to be mustered under MY lifeboat".  This incident should give pause to that idea.  I'm especially pleased that by the time we left for Antarctica Captain Jeroen had us muster both under the lifeboats and in alternate sheltered locations.

 

Roy

[3rdGenCunarder]

7 minutes ago, rafinmd said:

One thing I've frequently seen people post is "In an emergency I want to be mustered under MY lifeboat".  This incident should give pause to that idea.  I'm especially pleased that by the time we left for Antarctica Captain Jeroen had us muster both under the lifeboats and in alternate sheltered locations.

 

Roy

 

I've never had double muster drills, but it's an interesting suggestion. On one of our port days on K'dam this winter, the crew had a complete "abandon ship" drill. I listened to the announcements to get an idea of procedures. Muster is indoors, and when they  got to the "load lifeboats" stage, announcements said Muster station A please proceed to lifeboat 1, etc. They called a few boats in each announcement. So evacuation would go by stages, which would mean less crowding on decks and more space for crew to work. I've always wondered about crowding and room for crew to work when we mustered on deck on the other ships. Even without the life vests, passengers pretty much filled the space. Add that extra bulk and there would be nowhere at all for crew to move around. 

 

[Copper10-8]

8 minutes ago, 3rdGenCunarder said:

 

I've never had double muster drills, but it's an interesting suggestion. On one of our port days on K'dam this winter, the crew had a complete "abandon ship" drill. I listened to the announcements to get an idea of procedures. Muster is indoors, and when they  got to the "load lifeboats" stage, announcements said Muster station A please proceed to lifeboat 1, etc. They called a few boats in each announcement. So evacuation would go by stages, which would mean less crowding on decks and more space for crew to work. I've always wondered about crowding and room for crew to work when we mustered on deck on the other ships. Even without the life vests, passengers pretty much filled the space. Add that extra bulk and there would be nowhere at all for crew to move around. 

 

 

That's exactly how they did it two days ago during a fire/general emergency/abandon ship drill on K-dam

[rafinmd]

We didn't really have "double" muster drills.  We did it the usual way inr Fort Lauderdale and the indoor one was almost 30 days later.  We needed to do a second one anyway but I thought it very appropriate that we used a sheltered location as we headed to Antarctica.  They did the one for passengers boarding in Buenos Aires on deck, then again in  lounges at the 60-day mark.

 

With respect to preparing the lifeboats, I suspect the crew takes care of that at stage 2 when pax are supposed to be in their cabins.

 

Roy

[Copper10-8]

19 minutes ago, rafinmd said:

 

With respect to preparing the lifeboats, I suspect the crew takes care of that at stage 2 when pax are supposed to be in their cabins.

 

Roy

 

Correctamente, Roy!

[Hawaiidan]

21 hours ago, chengkp75 said:

Missed this in previous responses, but "hull speed" is not "top speed".  Hull speed is a calculation based on water line length, and represents the most efficient speed, not the top speed.  The fact that the Fletchers needed 120k horsepower to push that light and short of a ship to 34 knots means they were pushing far and away above hull speed.  Even the SS US was pushing over her hull speed, as similar length cruise ships today push far heavier ships at comparable speeds (think QM2) with far less horsepower.

Its been a few weeks since I stood engineering watch.... the correct shp for the Fletcher is 60,000 total  and run through a main reduction gear.     Hull speed is the most efficient. your right, above that your burning a lot of oil  .  So correct me 60,K total  twin screws

 

Thinking on  viking for a min.... since they are direct drive.... The engines need a lot of cooling.  a marine strainer could have gotten obstructed,  fuel contamination, Feed pumps, injector pumps..

The board of inquiry  will get to the bottom.     One wonders in a ship less than 2 years old would loose its new engines

[Hawaiidan]

[chengkp75]

5 minutes ago, Hawaiidan said:

Its been a few weeks since I stood engineering watch.... the correct shp for the Fletcher is 60,000 total  and run through a main reduction gear.     Hull speed is the most efficient. your right, above that your burning a lot of oil  .  So correct me 60,K total  twin screws

 

Thinking on  viking for a min.... since they are direct drive.... The engines need a lot of cooling.  a marine strainer could have gotten obstructed,  fuel contamination, Feed pumps, injector pumps..

The board of inquiry  will get to the bottom.     One wonders in a ship less than 2 years old would loose its new engines

The Viking Sky is not "direct drive".  The electric motor is directly connected to the shaft, but only turns at around a maximum of 125rpm, as this is as fast as a large propeller is efficient (the ship uses a variable frequency drive to change the 60Hz power generated by the generators into a variable frequency supply  for the propulsion motors so that an AC synchronous motor can run at speeds from 0-125rpm.  The engines, which require far more cooling than the electric motors are not  direct coupled to the electric motors, they are connected to generators.  Now, modern ships use mainly fresh water cooling for all machinery, the diesels and the electric motors, and then transfer the heat to sea water through plate heat exchangers.  With two engine  rooms (as mandated by SOLAS for newer ships), this means there are at minimum 4 main sea strainers (two for each engine room, so a minimum of two would have to clog at the same time to take out all engines).  Fuel contamination is pretty funny considering what the ships burn, which is very similar to what you burned in the boilers of the Fletcher class.  These engines will burn anything, and the fuel is filtered multiple times and centrifuged before it gets to the engines.  As for ancillary systems, each engine room has separate cooling pumps, and fuel supply pumps, and each engine has its own fuel injection pumps, lubricating oil pumps, and cooling water pumps.  This is the whole idea of redundancy, and the guiding principal of the Safe Return to Port requirements that the Viking ships are all built to meet.

 

And, yes, the Fletchers were 60k hp total, but that is still way above the power needed to push a 360-370 foot waterline (376 length overall) at hull speed.  The Fletchers, and all steam turbine powered ships used reduction gears for a couple of reasons.  One, you were coupling two turbines together, the high pressure (HP) and low pressure (LP) turbines which turn at different speeds, so to get them to turn a common output shaft, there needs to be some gearing between them.  The second reason is that a steam turbine is most efficient when turning at a couple of thousand rpms, while propellers need to turn less than 300 rpm, so you need to slow down the output shaft.

[Hawaiidan]

3 hours ago, chengkp75 said:

The Viking Sky is not "direct drive".  The electric motor is directly connected to the shaft, but only turns at around a maximum of 125rpm, as this is as fast as a large propeller is efficient (the ship uses a variable frequency drive to change the 60Hz power generated by the generators into a variable frequency supply  for the propulsion motors so that an AC synchronous motor can run at speeds from 0-125rpm.  The engines, which require far more cooling than the electric motors are not  direct coupled to the electric motors, they are connected to generators.  Now, modern ships use mainly fresh water cooling for all machinery, the diesels and the electric motors, and then transfer the heat to sea water through plate heat exchangers.  With two engine  rooms (as mandated by SOLAS for newer ships), this means there are at minimum 4 main sea strainers (two for each engine room, so a minimum of two would have to clog at the same time to take out all engines).  Fuel contamination is pretty funny considering what the ships burn, which is very similar to what you burned in the boilers of the Fletcher class.  These engines will burn anything, and the fuel is filtered multiple times and centrifuged before it gets to the engines.  As for ancillary systems, each engine room has separate cooling pumps, and fuel supply pumps, and each engine has its own fuel injection pumps, lubricating oil pumps, and cooling water pumps.  This is the whole idea of redundancy, and the guiding principal of the Safe Return to Port requirements that the Viking ships are all built to meet.

 

And, yes, the Fletchers were 60k hp total, but that is still way above the power needed to push a 360-370 foot waterline (376 length overall) at hull speed.  The Fletchers, and all steam turbine powered ships used reduction gears for a couple of reasons.  One, you were coupling two turbines together, the high pressure (HP) and low pressure (LP) turbines which turn at different speeds, so to get them to turn a common output shaft, there needs to be some gearing between them.  The second reason is that a steam turbine is most efficient when turning at a couple of thousand rpms, while propellers need to turn less than 300 rpm, so you need to slow down the output shaft.

In light of this.... what  would you guess would cause almost new engines to loose power    I do not know how many of her power plants went down.... I suspect more than 2