ANA Wants You to Go Before You Go
Here is how it works. The average bladder has a capacity of about 1 liter of liquid, which translates into just over 2 pounds. Let’s say the flight has 200 passengers, the total bladder weight of which can potentially be more than 400 pounds (the actual number is of course directly linked to the length of the ground delay and the resulting extra alcoholic beverages consumed by the passengers). And in a world where every airline (well, maybe not Air Koryo) is looking for a way to burn less fuel by doing everything from switching to lighter interior elements to adding winglets to using less exterior paint, 400 pounds is a LOT of weight.