Neither Man Nor His Machines Are Infallible
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John Nelson graduated from the U.S. Merchant Marine Academy at Kings Point, New York in 1965 and enjoyed a long career at sea on commercial and military support ships. After retiring from his seagoing career, he continued working in various capacities in the maritime industry until a final retirement in 2012. Since then he has been active in researching local history and restoring and operating steam engines and antique mills.
He lives in neighboring Panola County and is a long-time member of the Yalobusha Historical Society. He writes about his experiences in the Panolian, Oxford Eagle and Herald. He is also the uncle of Herald publisher David Howell.
After the years I’ve spent as chief engineer aboard various types of ocean-going ships, watching the container ship Dali crash into the Francis Scott Key Bridge brought back bad memories. It’s harrowing enough to lose all power at sea, but in a confined waterway like the Baltimore Harbor, it is terrifying.
Because of my experience, several friends have asked my opinion as to what might have led to the collision. Considering all the possibilities, it would be presumptuous to even try to pinpoint the cause. And It’s likely to take the U.S. Coast Guard and the National Transportation Safety Board months of combing through the evidence to make their findings public.
It is possible that I can use my experience to give readers an idea of what could have happened aboard the Dali in the moments before the disaster.
The ship was proceeding down the Patapsco River toward the Chesapeake Bay propelled by a slow-speed, cross-headed, diesel engine capable of producing a little over 55,000 HP from its nine cylinders. Of the ship’s four main diesel generators, it’s likely that three would have been on line to provide plenty of power for maneuvering.
With only a single propulsion engine, the reliability and safety factor is maintained by the redundancy of vital engine systems.
In other words, all crucial motor-driven pumps providing such essentials as cooling water and lubricating oil have backups that automatically come on line with the failure of the one in operation.
The auxiliary engines driving the ships generators have similar backups and there is additional protection to the electrical system since with the required number of generators on line to carry the ship’s maximum electrical load, there is always at least one generator on standby.
Even with such protections in place, there are some things that can cause power outages, and one is an interruption of fuel oil. Ship’s engines are called diesel engines after Rudolph Diesel who perfected the compression ignition system and not because they burn what we know as diesel fuel.
In fact, the propulsion engines of ships in commercial service burn some of the worst quality fuels imaginable, and with the increasing cost of fuels, the quality will not get better. It’s like the heavy oil burned in boilers and so viscous that it has to be heated to pump to the injectors.
The smaller auxiliary engines driving the ship’s generators usually burn a lighter oil, but it also has quality issues, and poor quality fuels lead to hundreds of power failures aboard ships each year.
The only way to minimize fuel failures is the careful handling of fuel by the ship’s engineers. That includes such things as the use of settling tanks and very exact monitoring of the ships purification system that uses centrifuges to remove water and contaminates before the fuel is sent to the engines.
Another thing that can shut down a ship’s plant is the very electronic/computer systems that we’ve grown to depend on to prevent such failures. Just as our computers and smart phones seem to play games with us at times, so do ship’s control systems.
With all that in mind, I’ve watched a video of the Dali colliding with the bridge several times. The ship is proceeding with the machinery described earlier in operation when she goes dark.
On the ship’s bridge, the captain and harbor pilot would have been under terrible stress and unable to do anything until the ship’s emergency generator located outside the engine room and on a separate fuel system came on line. Since one of the ships two steering units is required to be powered from the emergency switchboard, this would have provided steerage. Using the ship’s forward momentum and the rudder the captain would have tried to steer clear of the bridge.
The engine room would have been in darkness for the 20 to 30 seconds it takes for the emergency generator to come on line, and that would have seemed like an eternity to the men down there. Fresh air supply and exhaust fans would have stopped allowing a rapid buildup of heat and perhaps fuel fumes. Then with emergency power would have come a wave of blaring alarms and flashing lights so that one’s sensory system would seem under attack at the very time that quick, accurate decisions are required.
The emergency generator would have provided limited lighting to the engine spaces and given the engineers the electrical power to get the systems back on line to restore the operation of a main generator. And with a main generator on line, the systems to support the big propulsion engine would have become functional.
Soon after the lights come back on, the video shows a plume of black smoke billowing from the ship’s stack as the captain, realizing that he couldn’t steer clear of the bridge, likely put the engine on full astern to stop the ship’s forward momentum.
Even a ship of this size would have started to vibrate as the propeller bit into the water, and just when it might have seemed that disaster would be avoided, the video shows a second blackout that could have been caused by reasons already stated.
Or it could have happened because the engineers had managed to get just one main generator back on line, and the power surge from all the systems starting up had caused its breaker to fail.
With no chance of regaining power in time to avoid a collision, the captain dropped an anchor, but it would not be enough to check the ship’s momentum. The video seems to show things in slow motion as the ship maintains a collision course with the bridge.
Something that I will remember from the tragedy is that those reporting on the collision seemed to be in disbelief that such a disaster could have happened.
To keep things in perspective, one needs to remember that neither man nor the machines he creates will ever be infallible.
