You do good research Spo!
That is all me.You cut my head off and i will still try to bite your ankles 
addendum.
Besides some “friendlies” here call me AI chatbot without realising they are paying me a great complement .
In a certain way I am working in a similar way but a lot , lot , lot slower then chatbot using my own literature data base presented below. Honestly without it i would not be able to find my way to gCaptain forum 
.
But with it i can pretent to be … You know what
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KC,
This is an odd contradiction because when you view the video footage, the heavy black smoke is being blown to starboard indicating greater than calm conditions allied with a NE’ly wind direction.
This PR certainly raises some questions and queries.
I agree with spowiednick………it is a less than ideal and incomplete preliminary report.
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Fair enough. Let me refine my statement.
Winds were blowing NNE 15-20 at my house on Ches. Bay at approx. 0600 when I was awakened by phones calls about the incident. I had heard the NNE winds in my sleep for a couple hours prior to waking up. Now it appears meteorological data says it was calm at the accident site at the time of the incident. So 
. So, it appears wind was not a factor in the incident. Thank you for finding that data!
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Shouldn’t an rpm drop trigger some kind of progressive load shed before chopping the bus tie?
Hello Klaveness
Usually the trigger for the load shed or preferential trip is the current (Amps) on the bus - not power (kW) or rpm/frequency.
PS: Sometimes with the power factor less than design of 0.8 that may be experienced with so many transformers that are not fully loaded is a pain with the PMS system. PMS goes by power for starting stby generators, etc. For a given kW, the amps will be higher for a lower pf.
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Yes, there are definitely issues and limitations to the preliminary report. Winds looked like BF 1 to 2 or thereabouts.
In any case this discussion is at or past the point of diminishing returns. I don’t know enough about engineering to follow the discussion. Might be worthwhile checking scenarios involving the EDG against the ship’s lights in the video.
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KC,
Indeed and there is very little that I can further offer. The PR has basically left us flying blind.
We will wait for the final report by which time intensities and interest will have waned to a point of inevitability.
The final report recommendations will be the pivotal issue coming out of this detritus.
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I was really impressed with Engelec input. The Gent seems to me a real shark.
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Why not .Let’s debunk it.
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Not that easy, at least accurately.
I quickly checked it myself trying to not be influenced by previous posts.
I only found two YouTube videos, the well known StreamTime Live, full length, not edited, duration 7mn20s and a short one of 56 s.
There is also CCTV footage from traffic cameras but the way the video ends abruptly is a bit surprising though possible as the cables were probably severed at several places when the bridge collapsed.
Here I’m referring to the well known video as the two other ones don’t provide information about the power outages.
The StreamTime Live timestamp offset is surprisingly high, I checked randomly a couple of other live streams and the timestamp error was always exeeding 20 s (vs. my UTC time reference +/- 1 second which is not sync over the Internet).
Overall the time offset between the YouTube video and the times mentioned in the PR is around 23-24 seconds if considering that NTSB time indications are correct to the second where seconds are mentioned. As clocks are sychronized by GNSS, the ship master clock should always very accurate.
Times mentioned in the PR (Preliminary Report) which can be correlated to the video are coherent as far I can interpret the video.
The moment (PR: 01h26min02s EDT) when the VDR (Voyage Data Recorder) started receiving external data to be recorded doesn’t tell much as external devices interfaced by serial data communication require a more or less long but unknown delay to reboot after a power failure and begin transmitting data again to the Recording Control Unit of the VDR (the NTSB video only shows the bridge-console-mounted Operator Panel Unit). The same applies to signals with discrete interfacing (i.e. directly acquired analog and digital signals though it is unknown which optional data and signals are logged).
Beyond the formally mandatory data to be logged automatically by the VDR, optional data can also be recorded. VDR data is not only used in cases of incidents, it records various pertinent data which can be downloaded any time for further analysis.
Though I’m unable to add anything useful about the route I’d still like to know if in Fig. 7 Page 10 of the PR the scale is respected or if it’s just a fancy artist’s view. Especially the distance and time between Position 1 (1st blackout) and Position 2 (ME “shuts down”).
What does “shut down” mean exactly? When did the propeller stop rotating (if it stopped, even with engine shut down, the “windmilling” effect can turn the propeller)? When exactly was fuel injection shut down? The engine has no camshaft, each cylinder is controlled individually (fuel injection, exhaust valve, starting air valve, some lubrication functions,…) by the engine control electronics.
There is no mention about any ME start attempt, the wording is ambiguous, all I can interpret is that the ME could not be restarted successfully.
Takes just a few seconds to check the event history displayed by the MOP (Main Operating Panel of the ME) in the ME control room, which .
As I addressed it in other posts, I’d also like to know more about the black smoke, if any of the DG’s had been shut down, if the crew tried to restart any DG’s excepted DG2 which started automatically after the HV BUS lost power (and as alreay mentioned, it’s very odd that once the HV BUS was energized again, the supply of the LV BUS does not occur fully automatically; also as TR1 went offline, TR2 should have been put online fully automatically as the HV BUS remained fully normally powered during the whole duration of the 1st blackout, otherwise DGR1 and/or DGR2 would have tripped as it happened later causing the 2nd blackout, details have been discussed in my long annoying messages).
I’m unable to interpret anything more than everyone about the lights. Can’t see when the Emergency Generator comes online, I made a mistake about it and mentioned it.
Although not related to the video, I’d also like to know if someone tried to start the bow thruster, regardless of its possible effectiveness and how the 6.6 kV motor is started (drives a variable pitch propeller).
Also even with the basic Hyundai HiMAP the trip cause is displayed but not mentioned in the PR though I didn’t check the manuals, they’re hard to find and we don’t know the exact models and versions.
I expect that the whole power generation and distribution, both HV (High Voltage 6600 V, 60 Hz) and LV (Low Voltage, 440 V, 60 Hz), is from Hyundai but unfortunately unlike e.g. ABB or Siemens there’s nothing useful online. I don’t say those are bad products, I don’t know them. My experience is that with Asian manufacturers it’s often complicated to get direct support and not everything is available in English.
A more technical discussion is here:
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Is this the high-tech version of a potato up the exhaust pipe of the schoolbus?
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The little pipe is a turbocharger bypass line, used at high loads to limit supply to turbochargers and keep scavenge pressure within limits.
Trimmed by the head works, its a pain, but can give significant fuel savings. It depends on what draft you are operating at.
Also you only go by the head when sailing in open deep water.
Thanks. Interesting … from the days of worrying about not enough scavenge air and excess air ratio, to these days with high efficiency turbos to bleed off exhaust.
BTW, (may be old news), I came across this clip on HHI reverting to conventional low voltage systems. Suspect a couple of DGs will be installed below the accommodation block for shorter cable runs to the reefers.
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Yes it works and gives You fuel savings as COURSE STABILITY is better , what reduces ruder movements and hull resistance is as some argue less. It is a pain iin the ass though.
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Any boat I have ever steered loaded that way was squirrelly to steer by hand at best. I assume the effect scales?
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The foiling America’s Cup boats sail down by the head.
I remember that sometime around 15 years ago, Korean yards were using HV distribution systems for reefer load, HV cables run from the engine room along the passage ways where many smaller step-down transformers were installed. From these transformers low voltage cables run inside the cargo holds. Then they changed to a low voltage distribution system, where only few larger step-down transformers were installed in the engine room, then heavy low voltage cables run along the passage ways to the cargo hold. Somehow this was defeating the purpose of a HV distribution system, which is decreasing the size of the cables, however cost might have been an issue with those HV cables and many transformers in the passage ways.