Signing out now
Football is on😄
agree - not second guessing - but have to say if I am going to hit something - I am going to hit it going full astern and with the anchor down
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It’s all or nothing in Cardiff tonight.
Poland or bust.
Cmon Wales
And it’s all in Welsh and it is not my first language 
I’ve never worked on a marine slow speed with mechanical backups; the cooling water, LO and fuel booster/feeder/circ pumps were always independent electric pumps and they were typically not on the E-bus. The only mechanical pumps I’ve seen on modern slow speeds were the hydraulic pumps on an MAN ME, but those were only used once the engine was above a certain RPM. Below that RPM electric pumps were used to keep the pressure up.
The gist is that on a modern slow speed plant you’re going to lose propulsion when you lose power.
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completly understand the switch from steam to slow speed diesel engines. But as a mate, I was always aware that change came with an increased risk of at least hundreds of single point failures that can stop the screw from turning.
There’s a crew on the bow ready to drop the anchor when in restricted waters.
These incidents will lead to conjecture and one would assume that this particular instance will be fast tracked by the NTSB for analysis and report.
What is known is that the bridge collapsed owing to a single point failure. With the view that the relatively narrow shipping channel is directly adjacent to this support structure it begs two questions.
- With the view that transiting vessels are now much larger than when the bridge was built, were there studies undertaken to understand the ramifications of this support structure being compromised? We are now potentially dealing with vessels in the order of 150,000ts displacement.
- Why are larger vessels not escorted by a tethered centre lead aft tug capable of working indirect until clear of this support structure? Indirect towage can impart massive forces as opposed to direct towage. The most effective way to track and control the pivot point is the use of an indirect CLA tug.
It is easy to be wise after the event although these questions do need to be asked.
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I’m not sure that MAN is using common rail on their slow speeds, at least not on any of the newer ones I’ve worked on and not in any of the documentation I’ve seen for their models.
I do agree Aus ,
Thankfully I never had to think about vessels of this size passing under a bridge, but we did take 50,000dwt tankers under a bridge of that size. I never thought about a bridge strike as I was more concerned about having to drop an anchor near a submerged tunnel.
I honestly think the bridge would have survived a strike from a 50k tonne ship hitting it even almost head on but this was a bridge opened in 91 with quite impressive defences.
What kind of power redundancy do these large vessels have?
Compared to DP vessels that can improve redundancy by operating with open busbar on their PMS.
Oh no. It’s still pretty cold this time of year, too, people wouldn’t have long in the water if the fall didn’t get them. I was hoping luck would have the bridge empty, y’know?
A tug working indirect can have substantial effect on a vessel behind it in stopping or direction.
However the speeds involved in this incident were somewhere between direct and indirect.
Please a tugmaster jump in here.
As I understood it you have to be doing over 10kts for a tug to be effective indirect, hey and it looked awful scary from my point of view, then somewhere between 10 and 6 kts a tug is much better direct.
Please tugmasters jump in here.
My experience with tugs is from driving conventials, to being a pilot with twin voiths or twin ASDs.
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None. One main engine, one propellor.
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244,
I reviewed the AIS track of the “Klara Oldendorff” which is now alongside. She is a Panamax bulk carrier which transited inward under the bridge at 10.5 knots.
We regularly drilled tug crews, at their request, in indirect towage……particularly the newer training tug Masters. My experience is that is was incredibly effective at speeds as low as 5.5 knots to the point where I required no helm to transit a right angle bend. At times it was too effective and I needed to apply opposite helm to slow the rate of turn.
I was Piloting 300/50m loaded bulk carriers during these exercises displacing in excess of 200,000ts.
It has been determined, that at around 10 knots, indirect towage can impart a bollard pull in the order of 120~150ts in a tow line. We were always mindful on the stamped rating on the vessel’s bitts.
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On the electrical side of things, the most common layouts I’ve seen are three or four generators for electrical power production. I have enough generators online during a maneuver that I can lose one without blacking out. This usually means at least one generator can be in standby, though not always. I’ve worked two ships that required all generators to be online in order to use the bow and stern thrusters.
There are typically three switchboards, one that is for the emergency bus fed either through a bus tie off of the main bus or EDG and two that comprise the main bus. The two switchboards comprising the main bus are typically in the control room, the emergency switchboard is in or adjacent to the EDG room. It is possible to run with the main bus split though I’ve never seen that as common practice.
I have worked on ships with shaft gens. My experience has been with fixed pitch props though and we didn’t use the shaft gen while maneuvering. I have heard of CPP ships being able to run their shaft gen while maneuvering but I would have a difficult time being comfortable maneuvering without a separate generator online. I do not know the generator arrangement of the ship involved in the accident.
For propulsion, you’ve typically got the main engine and that’s it. And no, there’s not a lot of redundancy there.
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They avoided getting squashed by a RCH then, there was a little space all the way forward.
The water is around 44-48 degrees. Anyone not fished out by now is frozen 
Highly unlikely she had tugs when she did that.
I hope this posts correctly - radio traffic:
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