"When you cannot commit one calculation error."

Maiden voyage of World's Biggest Containership | YouTube

The introduction at YouTube [emphasis mine]: 

Mega Transports: Biggest Containership | Engineering Documentary

It is the largest heavy load transport on earth! The maiden voyage of the biggest containership of all times. 

When the first ship of the brand-new OOCL-fleet gets underway, more cargo is moved at one time than anywhere else in the world and never before.

At 21,100 TEU capacity, the vessel is the largest ever ordered to date. 400 meters long and about as wide as a football field (58.8 meters).

These mega-cargo ships will not only be able to load more cargo than ever before, they will also be equipped with a number of high-class energy-saving systems.

This Episode shows the maiden voyage of the OOCL HONG KONG. Everything happens for the first time: the captain, the pilots and the harbour crew have never before manoeuvred a giant ship like this. Berthing, loading, steering: risky manoeuvres, which have never been tested [in real time] before.

Once berthed, the cargo loading pushes everyone involved to the limit -- crew, crane operators and the lashing team. A loading procedure like this, with additional containers on top of the so-far known stacking limit, has only been theoretically discussed, but never tested in real life.

Balancing the ship, moving and securing the stunning mass of containers is a task that does not allow even the slightest mistake. 

The route from Shanghai to Rotterdam, with stop in Singapore, brings constant challenges: pirate areas, onboard emergency drills and the navigation through the narrow waters of the Suez Canal. All of this happens under incredibly high pressure of time.

Will the world’s largest container ship stay on schedule on its maiden voyage?

The 48-minute documentary, published February 2020, gives the audience a front-row seat to an amazing ship's journey.  

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