I captained a sea-faring ship like the Dali for 13 years. Here's a breakdown of what happens in a crisis like this.

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• Sachin Saxena is a former ship captain who spent 13 years navigating the globe on large ships. 
• He breaks down the processes of entering and exiting ports in big vehicles like the Dali.
• In emergencies like power failures, a ship can't just stop and there's a lot of pressure onboard. 

This as-told-to essay is based on a conversation with Sachin Saxena...