The vessel was en-route from Yantian, China to Long Beach, USA when it encountered a storm cell producing gale-force winds and large swells which caused the ONE Apus to roll heavily resulting in the containers to dislodge and fall into the ocean. The Master diverted the vessel to ensure the ongoing safety of the crew and ship until conditions eased.
If that report on the MSC Zoe is correct that crew there reported 30 degree rolls when the ship only rolled about 15 degrees. Crew fooled by the high acceleration.
The crew has under these extreme circumstances to deal with a complex mix of combined vertical, tranverse and pitch accelerations so it is imaginable that the situation seems worse then it is in reality. Senses are easily fooled sometimes.
They mention large swells not waves. How large is large? It is a pity that the wave height isn’t mentioned. The accuracy of wave height often also leaves to be desired, it isn’t easy to estimate it by sight. We often related it to the distance from sea level to bridge deck.
The observations were made at night. I don’t know if the deck lights were illuminated before the stow started to collapse but I suspect that they were only turned on afterwards.
Acceleration can cause inclinometers of the pendulum type to give a higher reading than actual.
Once, while pushing a “Deep Notch” oil barge in the Gulf, with appx 40’ -45’ or so height of eye in the lower wheelhouse had a window bust out. (Broad daylight) Was in about 10-12 foot seas a bit bumpy but riding ok. Out of nowhere a sea/swell popped up and broke a few lower wh windows. Rogue wave or what? Put the windows in (Actually plywood we had precut for a spare) and kept pushing.,Didn’t see anything like that the rest of the trip. Always seemed the weather around NW of Tortugas was beautiful and horrible at times. As was Hatteras. The depths changed so much.
I think most crew was asleep with only a junior officer on the bridge. It was pitch dark in the middle of the night and you couldn’t see anything outside. It was full speed as per plan. So the ship lost some badly secured deck cargo which nobody heard, felt or noticed. Nobody got hurt. It will happen again.
The news release says the One Apus was rolling heavily but it’s possible the rolls may have been quick 15 degree rolls. Same as the MSC Zoe, high acceleration mistaken for heavy rolling.
You often see that the containers at the extreme ends, aft and forward, break free due to the pitch acceleration forces at these locations. This pitch force adds up to the other forces such as the dominant transverse acceleration forces. At the bow the acceleration is 5.5 m/sec² en at the stern 4.5 m/sec².
The bridge is at about 150 m from AP where the pitch acceleration is only 0.38 m/sec². The dominant acceleration here is the transverse acceleration. For a roll of 15° this is about 4 m/sec² and for one of 30° about 8 m/sec². You have to hold tight, cling to something up there…
It almost looks like a wave motion went through the ship girder. As you rightly point out the acceleration at the ends of the vessel can explain the collapse of the stow in these areas but there are 2 other areas. They are almost equidistant from each other.
The MSC Zoe shows a different pattern. The container stacks forward and aft are in tact. Here the ones in the middle of the ship are affected. Wave height was here much less, 5 - 7 meters. Most damage was done by a group of higher waves according to a report.
You often see that the containers at the extreme ends, aft and forward, break free due to the pitch acceleration forces at these locations. But not on this picture.
Obviously, you have never set foot aboard a containership, much less sailed on one before.
What people on the street think what happens aboard a modern containership today, compared to what happened on box ships 30 years ago, and considering what SHOULD be happening onboard modern ocean transportation platforms now, are three entirely different things.
Yes, the “reports” made by ONE don’t seem to go along with larger view of ocean conditions displayed by WX service. I suspect some poor guy in their home office hurriedly put a statement out using info handed to him. The original condition of Force 4 WX they provided hardly seem enough to cause such extensive mayhem.
It underscores logbook entries regarding actual WX conditions. You never know WHO and WHY somebody will be reviewing it later.
Agree with you. I’m onboard box ships daily, just as they complete cargo, finish lashing, and are getting ready to sail.
It’s somewhat of a joke to see so many people think the C/M is ‘walking the deck’ inspecting lashings, carrying a piece of paper in his hand (the infamous manifest) and reviewing the stack of over 2000 boxes to ensure each individual one is properly stowed and away the correct distance from another HAZMAT box. Ha ha ha ha…like some kind of old
B-movie from the 1950’s
Meanwhile, the terminal is screaming at the Master via cell phone “Why aren’t you underway yet??? You haven’t even left the dock and you’re already late!!” That call is from some guy, half a world away who has no idea what’s happening, other than he can’t see his ship on the AIS screen where it SHOULD be by now.
The reality of modern cargo handling at the direction of those holding an MBA and not a seafaring officer’s license.
It doesn’t surprise me. The bridge of the ONE Apus is a long way from the water surface. The higher the observation point, the easier it is to underestimate wave heights. This is obvious when going from the bridge of even an average size container ship down to boarding a pilot or rescue boat.
Yessir! And the less experience the new mate on watch has (or an “old mate” who is new to these types of ships), the tendency would naturally be to underestimate sea/swell height.
But reading the anemometer shouldn’t be too challenging, eh? Assuming they have one that actually works and is properly mounted on top the bridge or somewhere with a clean air flow.
THAT actually is a huge assumption these days from what I’ve seen on most bridges.
Yes, precisely. The officers on watch have their own ‘first hand’ knowledge based on direct observation.
But the correct question is what was the actual WX condition where the ship was located exactly???
I saw a track line a while back online but can’t recall it’s precise Lat/Lon and overlay that onto a weather analysis for their position. That would help the discussion.
