We don't often associate airplanes with low-hanging fruit. I mean, it might just be the worst metaphor one could imagine. After all, planes spend a lot of time entirely out of reach. But when it comes to finding ways to save fuel and reduce carbon emissions, there's lots of low hanging fruit.

The automobile industry has invested billions reducing the weight of their cars to reduce fuel consumption and they don't even have to lift them off the ground. So it's no surprise to hear that airlines are saving millions by reducing weight. What's surprising is that they haven't done more of that sooner.

The opportunity is enormous. Researchers at MIT estimate that that cost of each passenger carrying a cellphone costs Southwest Airlines $1.2 million annually in weight-related fuel expenses. That number jumps to $21.6 million if the cellphone is replaced by a laptop. Other pundits have pointed out that if every passenger used the bathroom before boarding the plane, it could save the airline millions. This caused budget airline Ryanair to consider charging passengers to use the bathrooms in flight (to encourage them to plan ahead).

Virgin Atlantic estimates that shaving even a single pound off all the planes in their fleet would save them 14,000 gallons of fuel per year. The airline has redesigned its meal trays, an exercise that was originally intended to improve the customer dining experience. Turns out they could fit more of the smaller, lighter trays on each meal cart, which means fewer meal carts per plane. The net result is close to a 300-pound weight loss. It's a great example of the kind of rewards that creative thinking, and a willingness to think outside the box, can bring. American Airlines launched their FuelSmart program in 2005, which has utilized a number of employee suggestions on ways to save fuel. Since its inception the program has saved a billion gallons or more. Some suggestions include cutting back on usage of auxiliary power, when on the ground, single engine taxiing, engine cleaning, high speed towing and adding winglets.

Specific weight-reduction measures include:



Removing unnecessary cabin equipment.



Replacing cargo liners and containers with lighter-weight materials



Replacing American's catering carts with newer models made with lighter materials



Reducing potable water amounts, replacing flight bag documentation with iPads.

All told these improvements save a combined 10 million gallons of fuel per year.

Longer term, there are, of course, entirely new designs utilizing materials like the carbon fiber substitutions in the Boeing 787 Dreamliner. Boeing estimates weight savings of 20 percent compared to aluminum, which is represents tremendous savings over the life of an airplane.

Image credit: happyrelm: Flickr Creative Commons

RP Siegel, PE, is an author, inventor and consultant. He has written for numerous publications ranging from Huffington Post to Mechanical Engineering. He and Roger Saillant co-wrote the eco-thriller Vapor Trails. RP sees it as his mission to help articulate and clarify the problems and challenges confronting our planet at this time, as well as the steadily emerging list of proposed solutions. His uniquely combined engineering and humanities background help to bring both global perspective and analytical detail to bear on the questions at hand.

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