Be prepared, be practical, and be positive.
In the wee hours of the morning on August 8, a fire in the Atlanta headquarters of Delta Airlines led to a power outage and caused a global meltdown of their computer systems. This caused delays and cancellations of more than 2000 flights over the next two days. It also disrupted scheduling and turnover of flight crews, issuing of boarding passes and baggage handling. How a simple power outage could lead to global shut down of an international airline like Delta is a separate discussion: generators and backup systems are meant to avoid just such a scenario.
Ranjan's Writings 