Glad we weren't on the Lochmaddy pontoon ....

What happened to cause it could be quite simple. About 10 years ago, I was on an ROV vessel working in the North Sea where we very nearly collided with a major oil platform, because the 1st Officer had put the centre of the platform as our destination. Unfortunately, he didn't know how to exit the programme and regain manual control, as the version on that ship, was subtly different to the version that he was used to. Manual control was reinstated 200 metres or so, away from the platform, this also being a violation due to having entered the 500 metres zone. To regain control, they woke the Captain.....! I believe that the SOP afterwards was to have the destination entered into a safe zone.
As supernumaries onboard, we were unaware of this, then surprised to say the least that this could happen. On the CalMac, could it perhaps be that the computer simply crashed, and that the override 'switch' was U/S?
 
awol said:
LOTI is being put on the Uig run. Hebrides is heading for the Greenock graving dock and they reckon about a week to get there. At the moment the Queen Mary is occupying the dock.
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I guess they will need to wait for the forecast "F9 possibly F10" to pass before attempting to get Hebrides off the Lochmaddy pier and south round the Mull. Not a good day for it.
 
Minchsailor said:
I think it may be the third in recent years. The Kenncraig - Islay ferry has seemed to be very prone to 'missing reverse'.

On the subject of a substitute; I suspect CalMac may be struggling. This is the time for the ships to go off station for winter refit, which means their relief fleet must be stretched. The Minch needs quite a seaworthy ship and I don't think the smaller boats, like the drive through's, would be licensed to operate. The ex-Stornoway ferry, Isle of Lewis, may be available, but it could be a bit big for getting into Tarbet (or even Lochmady). Interesting to see what they come up with.
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They are not the only ones to have a few issues.
Most major operators have a few skeletons in the cupboard or under the carpet.
Things happen, lots of little things happen. Every now and then, when the little things add up. A bigger thing happens.
Fortunately no one hurt. It will all buff out.
A lot of logistics to figure out to get service back up and running and find somewhere with available space to make repairs.
 
I hope CalMac are more forthcoming about the incident than the Isle of Man Steam Packet (although I imagine the MAIB will be). A few years ago Manx Radio reported that an incoming ferry had boffed the quay in Douglas with its bow.

The Steam Racket's...sorry, Packet's...instant response was to deny it (a common trait on Mona's Isle). This was not altogether a good idea for two reasons:
1. the ferry had physically imprinted part of its 'three-legs' bow logo on the harbour masonry.
2. Manx Radio has the best possible view of Douglas harbour. The reporter had actually seen it happen.
 
JumbleDuck said:
There are several reports of that happening to other ships on the MAIB website. It's not endemic, but it happens regularly.
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Actually its a very rare occurrence. Although it has happened several times.

Pure idol speculation. there are many reasons why this incident may have happened but a failure of the CPP is a possible.

There are a number of different possible failures in a CPP system. (Controllable Pitch Propeller)
First the control system. Ie the big knob (not the Captain) on the consul on the bridge. Older ships were often Pneumatic air control ( was very reliable) Newer ships are more likely fly by wire. Control head's cheep plastic knob. electronic system to the OD Box (Oil Distribution) for the hydraulics which operate the system.

One of the issues with a CPP hydraulic failure, its much harder to figure out what the heck is wrong than with a control failure, If it has failed in an ahead mode and you are trying to slow down or stop.
An emergency engine shut down may be required.

Depending upon how far away from the dock you routinely slow down. It can be one of those by the time you go through the all the check list things where the you get to the relevant part just after the crash.
Most ships of this type are twin CPP.

The control systems are completely separate. It would be incredibly unlikely for both to fail at the same time. ( spill a coffee on consul and short both out, has been done)
The only common component is usually the operator.
This system is usually full feed back, Ie set the knob to desired Pitch Setting. the CPP will follow to this setting.

If the system fails there is usually a Non follow up Back Up system to the hydraulic pumps which by pass this system. Effectively it is just an on off button for the pump hold button pitch moves until you release it, one for ahead another for astern.

Most ships will also have a telegraph system. pretty much like the old movies it just relays a message to the engineer to take over control and what to set it to.

The ECR console usually has both the follow up and non follow up CPP controls as well.

There being a strong possibility if the Bridge console has failed the failure may be further down the line and the ECR console may not work.

There will usually be a direct solenoid or lever on the hydraulic pump right by the OD box with a telegraph. Which can be operated by an engineer local at the OD box.

If its nota control failure there is a possibility the CPP hydraulic system can fail by loss of oil or oil pressure.

There three basic different ways the CPP may respond depending upon manufacturer and design. And two very different schools of thought.

Older system had only two options.
Most were spring loaded. an oil failure failure the spring would take over.
Some default to a zero Pitch setting. You have no pitch function and can apply no power.
Some default to full ahead Pitch Setting, The idea being after you get sorted you can still operate as a normal propeller. a get you home or away from danger mode.
As you can see this may not be the ideal situation if you are approaching a ferry dock. or a marina.

Some more modern systems will lock in place of last setting. also could be a problem if you are approaching a dock.

Most operators of ships with CPP have rigorous testing regimes prior to departure. Most longer haul operators will test astern pitch as part of their pre-docking checks.

Smaller vessels doing very frequent docking, Look at it as it was just fully tested an hour ago when we were in and out the last dock. The likelihood of this failure being low.

Additionally this type of system is very reliable, but when they fail they tend to fail when under high stress, rather than a low stress function test.
 
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Looks like MV Hebrides is on the move again, heading south towards the Clyde after a short pootle about off Loch Maddy - perhaps testing their control systems?
Not going at full speed yet - whether due to wind / waves or any propulsion concerns
 
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