Cruise ship Viking Sky sends out a mayday call,

[hpeer]

Transmitterdan,

If you use the El Faro as a guideline.

1 Engineer did not know of the low oil vulnerability.
2 As in above Norwegian case the tank was low but “normal.”
3 One reserve tank was partially full, enough to help.
4 Other reserve tank was empty.
5 There is no prefailure warning, it sounds like the alarm went off about the same time the engine stopped.

[hpeer]

Sometimes my mind wanders and I wonder what the control room for the Global Financial System looks like. What alarms they have, what redundancy, how much “spare oil” they carry, if the operators have read the manual.

Did the passengers know what peril they were in? Do we?

Be happy, don’t worry. LOL

[transmitterdan]

Originally Posted by hpeer

Transmitterdan,

If you use the El Faro as a guideline.

1 Engineer did not know of the low oil vulnerability.
2 As in above Norwegian case the tank was low but “normal.”
3 One reserve tank was partially full, enough to help.
4 Other reserve tank was empty.
5 There is no prefailure warning, it sounds like the alarm went off about the same time the engine stopped.

Thanks for this. Surely it should
be safety item to have the sump “full” and not just “above low” before a huge passenger ship puts to sea.

Yeah, i read the bit about the low oil level alarm preceded engine shutdown by only a few minutes. That seems like a design issue.

[a64pilot]

Originally Posted by CSY Man

Yeah, it is on the Runaway Stab Checklist. Been practicing it in the flight simulators for 30 years, nothing new. No idea why why these guys crashing the MAX planes did not think of it...

I’m sure they didn’t know what was going on.
There was no Master Caution segment light marked stab runaway to tell them what was happening.
In other words, they didn’t understand the systems on the aircraft, which is something that I’m having a hard time understanding.

Read this, this scares me on several levels. They had plenty of time to read checklist, even discuss what was happening, I can assume that even in the Simulator that they didn’t fly the aircraft manually due to the over controlling etc
https://en.m.wikipedia.org/wiki/Air_France_Flight_447

The more automation takes over, aircraft, cruise ships etc., the more we become at best, systems managers, and not pilots, seamen etc.

How long did it take to figure out the cruise ships engines shut down due to low oil level / pressure?
Surely there were warning lights, codes etc?
Why weren’t they restarted pretty quickly?

[JPA Cate]

Don't know about the cruise ship procedure, but a friend's engine goes through a pre-determined electronic checklist, and if all systems are not "go", it cannot be started. A safety feature that saves the engine while the boat drags ashore, that I think is desperately unsafe! The ship's engines may have a similar self-protective setup: oil sloshed away from sensor, oops! mustn't start!

Ann

[transmitterdan]

Ann,

You raise a good point. There are times where you would be willing to risk losing an engine to avoid a greater risk like the rocks off the coast of Norway.

What boggles my mind is the number of hours they were adrift and could not correct a basic maintenance item (put some oil in and restart). I hope we don’t find out that the ship’s engineer could not even put oil in the engine. Or worse, there was no oil on board.

These may be gas turbines, not sure. But some engines are more complex than others. Still it seems prudent to have someone onboard qualified to take such a minor maintenance action as lifting the hood and putting in some oil. But then i think about all the automobile drivers incapable of doing the same. Sigh...

[oslokid]

A possible reason for failure of multiple engines is water coolant intakes sucking air. There is supposedly two water intakes, one for calm waters or in port and another further down in the hull. They were possibly running with the water intake higher up.

Info on Viking Sea:
https://www.fincantieri.com/en/produ...ps/viking-sea/

Info on the 6MW engines :
https://marine.mandieselturbo.com/do...r.pdf?sfvrsn=4

[hpeer]

Again going back to El Faro, that ship, single engine, had reserve tanks capable of several thousand gallons of oil. One was empty and one had a couple of thousand gallons. But the restart procedure is quite cumbersome, the pick up needs to be bled, etc. IIRC.

[GordMay]

Originally Posted by transmitterdan

... These may be gas turbines, not sure. But some engines are more complex than others ... Sigh...

Viking Sky is equipped with four MAN 32/44CR engines powering Rolls-Royce Promas propulsion and manoeuvring system. The Promas system incorporates the propeller and the rudder in a single unit to increase the hydrodynamic efficiency. The propulsion unit includes six-bladed 4.5m-diameter fixed-pitch mono-block propellers.
Rudders and propellers were designed and developed by the Rolls-Royce Hydrodynamic Research Centre in Sweden. The model testing of the Promas system was performed by MARIN.
➥ https://www.ship-technology.com/proj...y-cruise-ship/

The current MAN 32/44CR engine represents the newest technologies in the area of medium speed operated industrial sized diesel engines. By the use of electronic injection, high efficiency turbochargers, electronic hardware and variable valve timing the 32/44CR is a synthesis of the most advanced large engine technologies available.
➥ https://marine.man-es.com/four-strok...2-44cr/profile

Promas integrates the propeller and the rudder into a single system to optimise hydrodynamic efficiency. A special hubcap is fitted to the propeller which streamlines the flow onto a bulb that is added to the rudder, effectively reducing flow separation immediately after the propeller.
➥ https://www.rolls-royce.com/products...al-information

[a64pilot]

[QUOTE=JPA Cate;2857978]Don't know about the cruise ship procedure, but a friend's engine goes through a pre-determined electronic checklist, and if all systems are not "go", it cannot be started. A safety feature that saves the engine while the boat drags ashore, that I think is desperately unsafe! The ship's engines may have a similar self-protective setup: oil sloshed away from sensor, oops! mustn't start!



Most computer controlled engines run a bit or built in test prior to starting.
On older systems the self protect switches for overheat, low oil pressure etc are called “Murphy” switches.
Most of our generators for example have two Murphy switches, one overheat and another low oil pressure.
If don’t know where the Murphy switches are, and how to bypass them, you can’t call yourself a mechanic in my opinion.

Parallels exist in all kinds of places, for example on the Apache helicopter there was a FDLS system, fault location and detection system, it had many sensors, the main transmission temperature transducers unfortunately drew power from the engine start system, if a transmission temp transducer shorted out, you could not start the engines.
Also it’s real important for a turbine engine to not be overheated during start, it can cost huge amounts of money of one is, so therefore the engines had a hot start preventer which would shut down the engine if it exceeded 900C during a start.

We knew how to disable both systems, never had to, never heard of anyone having to, but we all knew the systems well enough to know how to defeat them if it became necessary.

I can’t imagine a “real” ships engineer couldn’t diagnose the reason for the engines to shut down and either bypass that system, or take corrective action to get the engines going.

However in this day and age, where they are mostly parts changers, and God forbid if they actually did bypass a system they would likely be fired.

It’s “progress”

[Jim Cate]

"thousands of gallons of lube oil"???

How much oil would typically be in use in such an engine? I have no scale concept here, but a whole swimming pool of extra oil boggles my small time brain!

Jim

[transmitterdan]

It’s many barrels of lube oil. Maybe not “thousands of gallons” but still “lots” of gallons and “bunches” of liters.

[GILow]

Originally Posted by Jim Cate

"thousands of gallons of lube oil"???

How much oil would typically be in use in such an engine? I have no scale concept here, but a whole swimming pool of extra oil boggles my small time brain!

Feels about right, from changing the oil on my old Nissan engine.

[Jim Cate]

This is all interesting to me... the scale factor for really big engines! So, how much lube oil would such engines consume during a voyage, or say per day at nominal economic cruise speed? I suspect that it is a LOT, or else they would not fit such large tanks for spare oil.

Jim

[jimbunyard]

Couldn't resist. That specific class of ship uses either a 12 or 16 cylinder Wärtsilä V46D engine; for sheer scaling impressiveness I'll assume it has the 233 ton monster 16v engine.

Actually the engine is kinda midsized, with a piston diameter of 'only' about half a meter...

Anyway, the engine has a dry sump , so I assume the 'low oil shutdown' was a low oil pressure shutdown, but I suppose that's just splitting hairs.

As for recommended capacity of the oil tank, for the 16V, it is 26.3 cubic meters, which translates to 6947.725 gallons.

For more than anyone probably wants to know about the engine

https://www.wartsila.com/docs/defaul...=msleadscoring