Himap are rebranded Symap protection relays manufactured under license by Hyundai. Symap are designed and made in Germany by Stucke. They are very good products with event and fault recording capabilities.
Does that really count when they’re on a foil they can adjust the angle of with an Xbox controller?
Gentleman
I hear all your discussions about steering effect head down head up etc.
Can I reiterate.
I can only base my experience on once berthing a Dali sister ship.
But please believe me there were no issues at all with the rudder response.
Believe me our terminal that I berthed her at was challenging for any large ISH container ships. But that size was getting on for the largest that terminal could handle.
We did a few Cap San class Hamburg Sud ships at 333m and just one an S class maersk at 350m.
And numerous Panamax size.
I probably did multiple hundreds of large container ships to that terminal.
I would have noticed… Honest
And just for the record I did multiple hundreds of larger ships to our newer container terminal up to the very largest at 400m but the terminal approach was/ is nowhere near as difficult with regards to manoeuvring apart from the distance available for swinging.
Per the article these transformers probably in the 1200-1500kva range are located inside the cargo holds. Wonder if this space is enclosed with access, ventilation, etc and where the access is from. Just open to the cargo hold does not make sense with HV.
Suspect Dali maybe the same arrangement.
Hi 244
I hear you. I too believe there must have been some response to the rudder with no engines at the 7-8 kts speed. 118 makes a compelling argument, but zero response of the vessel heading is very remote imo. Given the EDG came on and stayed on until contact and therefore the SG pump 3 operational, something is amiss.
OK. Have examined Admirality NP 69 and Guide to Port Entry as per below:
Basis the delineation of Baltimore port limits as per above 6.104
have found and downloaded the following 4 docs .
Section 08.18.19.01 - Patapsco River.pdf (70.8 KB)
Section 08.18.19.02 - Upper Patapsco River.pdf (74.2 KB)
Section 08.18.19.03 - Patapsco River South Shore.pdf (91.9 KB)
Section 08.18.19.04 - Patapsco River North Shore.pdf (83.3 KB)
The docs ( issued by AUTHORITY) define maximum speed of 6 kts . Can anybody with local knowledge confirm it as then it should be valid question why Dali speed with her draft of 39.9 ft was 8+ kts.
Under one of the utube videos on Dali allision have found the following comment :
QUOTE:
The ship was not “In the Channel”, they were “In Port” and there are regulations that dictate the speeds that a vessel of any size may move within that area of operations. In this case, the regulation for a ship exceeding 10,000 gross tons is no greater than 3 knots until they clear the Key Bridge and are “outside” the port. So WHY was the ship traveling at 9 knots?
END QUOTE
addendum:
speed limits
CPB3_C15_WEB.pdf (noaa.gov)
patapsco_river.pdf (15.2 KB)
Absolutely agree. Frequently when doing dead ship in open waters as we unfortunately frequently have in the last few years, I tell the helmsman, “let me know when you lose rudder control”. It invariably happens around or just below 2-2.5k kts, not before. A skilled helmsman can effectively maintain designated heading at 3-3.5kts until full/hard rudder i/ seagoing experience no longer effective. At the speeds from 8.5 - 6.4 it is pure inexperience or a purposeful distraction of some kind to discount rudder authority.
Of course there is a significant rudder response at 6-8 kts. For crying out loud anyone on the bridge for several years having gone black knows this. What agenda is being pushed and why?
There is a huge volume of empirical & hands on experience material and science relating to ship handling. Regret to observe , that some extolling ad nauseam their practical experiences and achievements completely ignore the science.
The report says that "without the propeller turning, the rudder would have been less effective " - That’s correct.
According to the report when power was lost the first time the rudder was amidships, the heading was 141.7 °. When the power was regained the heading was 144.3 °.
So the ship was in a gradual turn to starboard when it was about three ship lengths from the bridge and wheel was ordered to port.
This was where she ended up,
The effects of wind and current, interactions with the bottom are not known.
Hi KC
How do we know the rudder was midships at the blackout? Fair to assume the vessel was on hand steering. Maybe the rudder was a couple of degrees stbd at the moment of blackout (may explain the heading change). Possible when the EDG and SG pump 3 came on, the rudder managed to get to midships and stayed there unresponsive to rudder commands.
I should have said “according to the report”. Edited my post.
In my experiance Ship Handling deep draft vessels in narrow channels is way more art than science. 
Thanks - a heading change of about 2.5 deg in a minute or so - should be overcome with 20-30 deg of right rudder on a ship doing 6-7 kts through the water.
I remain skeptical that amount of rudder was ever applied. I guess I will have to wait for some additional information. The answer is known - I am sure that at least one of the pilots, or the master, or the mate, or the helmsmen took a look at the rudder angle indicator after the helm orders were given.
I agree without any further questions .
And i will even attempt to rise the gloryfying ante : IMHO it is an ART competing with MAGIC. 
Sir yes Sir.
But one must agree that nawadays even an art mixed with magic can be described with binary formulas .
sorry left rudder !!!
I would never allow autopilot or “track mode” in such conditions. Always all available pumps “on” and hand steering. Only checking ruder angle is in sort of “auto mode” as reflex action. Bow thruster although not used will be fully on line just in case shit happens and tugs are gone.
It’s a probability thing, the way the report was worded it’s somewhat ambiguous, leaves room for questions,.
Aside from environmental factors there’s also the uncertainty wrt the diagram, Presumably the track is that of the GPS antenna which would likely have been near the pivot point. The rudder may have in fact checked up the swing to starboard and started a swing to port, don’t know. Also there’s advance and transfer.
The gyrocompass data must have been recorded but I don’t remember the required sampling interval.
Chief MAKOI has uploaded a new video addressing some points, maybe it could be interesting to start a specific topic.
Indeed the design of reliable redundant power supply systems is a well-known subject, among critical power supply systems one can mention nuclear power plants, Oil & Gas platforms, DPS vessels, process industries, thermal power plants (hydroelectric power plants are less critical).
The steering gear lost power as the 1st blackout occurred around 01h24mn54s EDT (real time, not video timestamp). Due to the low inertia of the pumps and motors, the steering gear ended locked at 0° (PR (NTSB Preliminary Report) page 10). In such case the rudder won’t move unless the torque on the rudder stock becomes so high that overpressure valves will allow the rudder to move in order to avoid overpressure and cavitation of the plunger cylinders but there is no reason such high torque would occur here (steering gear torque of very large vessels can exceed 1’000 kNm, or let’s say a torque corresponding to “1000 tons with a lever length of 1 meter (approx. 39.4”)).
Details should be checked referring to the detailed hydraulic diagram “as built” as they can vary.
I suppose the rudder angle indicators were supplied by the 24 V DC battery-backed supply, there are 2 angle sensors, typically with some flimsy linkage, not a double magnetostrictive measurement with each redundant electronics (i.e. a 4-channel measurement, possibly with diversitary outputs signals like e.g. 4-20 mA in one and the other 4-20 mA in the opposite direction, which allows controls to monitor discrepancies, the same should apply to helm transmitters if analog, if digital abolute SSI it can also be implemented but overall despite hundreds of millions US$ at stake, automation redundancies of merchant vessels are surprisingly basic.
At least in theory, the Emergency Generator (EG) should have come online within 45 seconds after the beginning of the 1st blackout, i.e. not after approx. 01h24mn54s + 45 s = 01h25mn39s EDT.
As the 1st blackout ended anyway around 01h25mn53s, all 3 hydraulic pumps could have been restarted at that time. Possibly the EG could have come online maybe after 12-15 seconds instead of 45 seconds which is the maximum allowed delay but as mentioned in the PR the exact moment is not known yet.
The question is more about restarting the steering gear, the selection of the different pumps can be done at least in some cases from the bridge (wheelhouse), which would be logical for a not permanently attended ME Control Room (as for M/S Dali and other modern container ships).
Another point to clarify is if the steering gear could be and has been effectively reverted to regular 3-pump mode as normal power was restablished at the end of the 1st blackout and at the the end of the 2nd blackout.
As the EG continued to supply emergency power even after the end of the 1st blackout including thoughout the full 2nd blackout, if for any reason the steering gear would have been remained locked in an emergency power mode preventing the use of all pumps allowing full performance this could have prevented full steering gear performance from the moment the EG came online to (probably) the allision.
The 2nd blackout did last around 31 seconds but emergency power was available without interruption during the whole 2nd blackout (after a blackout ends an EG does not immediately stop).
Can someone confirm if after a blackout the steering gear must be restarted manually from the bridge or the ME Control Room (if attended which was the case during the incident voyage) when emergency power is available and if when regular power is restablished it automatically reverts to unrestricted performance?
I ask regardless of any major or minor incidence in the discussed case as it’s still worth to be determined as possible lesson learned.
Typical steering gear controls are relatively basic and sometimes not even well designed (referring e.g. to an incident related to a very poor choice of hydraulic oil level monitoring combined with a wiring error… seems to not have been well tested, I must find the reference of the incident).