In my files, on my computer, I keep an Excel chart to track my mileage. Well, not my mileage, but my car’s. It tells me if my car is being good or bad, or if I should get rid of it. The car, not the Excel chart. I’ve been doing this for years, and about the only time I ever look at it is on the date of entry.
Then there’s my wife. She’s into apps, or to be more precise, Apps. It’s a relatively new word that is bound to wind up in the dictionary one day. Does anybody know what a dictionary is any more?
After Christmas, she found an iPod App to check her mileage. Well, not that mileage. She wants to know how many steps she takes in how many hours of walking, and to calculate her speed in miles per hour. Secretly, I think she’d like to get stopped by radar.
So I have a challenge for her. Since we’re so into cruising, I want her to calculate the fuel efficiency of cruise ships. Let’s see her stick that in her App.
Don’t tell her, but there’s an easier way. I found it in a marine article at brighthub.com. The short version of the story is that writer Erik Hinrichsen calculated that while Royal 
Caribbean’s Oasis of the Seas — taking the world’s largest ship as an example — gets .0023 miles per gallon. Translated, a gallon of fuel for every 12 feet it travels.
However, when Hinrichsen factored in the number of people who travel that 12 feet on a gallon of fuel, the revised mileage calculation became 19.36 miles per gallon, per person. That’s almost as good as my 11-year-old car. He also theorized that the Oasis, because it has more passengers, performs better than Royal Caribbean’s Voyager Class ships, which check in at 17.65 miles per gallon.
Using the same philosophy for jet liners — and cruise lines aren’t going to want to hear this — he discovered that a fully-loaded 747 has gas mileage of .15 miles per gallon…and 91 mpg/pp.
He didn’t need an App to figure this out. Nor even an Excel file.