Saving fuel

Other tools can be used as well. By their nature, airlines are heavily reliant on sophisticated scheduling practices. Arrivals and departures are scheduled based on everything from connecting flights to gate availability or routine maintenance. The one thing that can’t be controlled is the weather, but seasonal weather is considered with respect to adjusting flight times for the winds.

For pilots, the biggest control we have is over the efficient use of fuel. Many airlines use what is called a “cost index,” which is a means of measuring how cost efficient a flight is. The flight planning software takes this into account to maintain the schedule, because that is the one thing that passengers care about over and above everything else (after they have paid for the ticket, that is). If the flight schedule is running smoothly the cost index can be lowered by strategically flying slower or higher, both of which save fuel. It can also be adjusted upward if there is strong headwind or if the airplane is running behind schedule. Often, I begin a flight with a higher cost index in order to get back on schedule, and find myself able to slow down later, which saves money and keeps the bean counters satisfied.

Being early always sounds good, but it can lead to problems. When flights arrive early, the gate may not be available, and that can lead to ground congestion that can lead to more problems, especially in smaller, more crowded airports. More than once, I’ve landed early only to end up at the gate as much as 45 minutes late because the extra airplanes on the ground made it difficult to get the taxiways clear. It’s easy to forget how much that 100-plus feet of wings can complicate something as simple as making a turn.

We also save fuel by using reduced thrust on takeoff. There’s no point in going full blast on a cool day with a half-full airplane, so airlines use performance software to figure out exactly how much thrust is needed for a given runway, weight, and temperature combination. Not using full thrust unnecessarily can save millions of dollars each year, both in fuel costs and in engine wear-and-tear. (Full-thrust takeoffs are done on a schedule to confirm that the engines can still produce rated thrust.) Even landing with the correct flap setting can make a difference. The extra drag from a fully extended set of flaps leads to more thrust being used, which costs fuel.

Tankering fuel is also common when it is cost-effective to do so. Tankering means carrying extra fuel from an airport with relatively low fuel prices to one with relatively high prices in order to minimize the fuel bill on the next flight. Every airline does this routinely, and the savings add up. However, this has to be done judiciously, because carrying fuel requires fuel. As the saying goes, there ain’t nothin’ free.

Fuel is the lifeblood of aviation (along with cash). The price is always a moving target, so optimizing fuel saves money that can be used or invested elsewhere. Efficient fuel usage can be the difference between a flight making money and losing money, and nobody wants to work for a company that is losing money.