Airlines Fuel Cost Optimization

What are all about this, let's go through!

An operational flight plan is required to ensure an airplane meets all of the operational regulations for a specific flight, to give the flight crew information to help them conduct the flight safely, and to coordinate with air traffic control (ATC).

Computerized systems for calculating flight plans have been widely used for decades, but not all systems are the same. There are advantages to selecting a more capable system and using all of its analytical and optimization capabilities. Using the flight planning process to reduce fuel not only saves money but also helps the environment: carbon dioxide (CO2) emissions are directly proportional to fuel burn, with more than 20 pounds of CO2 emitted per U.S. gallon of fuel burned.

While flight plan calculations are necessary for safety and regulatory compliance, they also provide airlines with an opportunity for cost optimization by enabling them to determine the optimal route, altitudes, speeds, and amount of fuel to load on an airplane.

Optimization can be challenging because it involves a number of different elements. An optimized flight plan must not only take into account the correct physics (i.e., airplane performance and weather) but also route restrictions from ATC and all relevant regulatory restrictions. The mathematical nature of these constraints and the overall size of the calculation combine to make it a challenging problem, even by modern optimization standards. Some of the equations that describe the behavior are nonlinear and non-continuous, and the airplane state is dynamic (i.e., it depends on how the airplane has gotten to a specific point, not just where it is). As a result, tens to hundreds of thousands of individual calculations are required for a single flight.

An optimal flight planning scenario for saving fuel and emissions involves calculating multiple routes or operating approaches for each flight, ranking these scenarios by total cost, choosing the scenario that best accomplishes the airline's cost objectives, and providing summaries of the other scenarios for operational flexibility.

While the scenario chosen by the system might be used most of the time, dispatchers and operations managers at an airline's control center may choose another scenario to meet the airline's operational goals, such as routing of airplanes, crews, and passengers. Because they are often making these decisions shortly before departure time, a user-friendly presentation of the relevant information is vital.

The best route to fly depends on the actual conditions for each flight. These include the forecast upper air winds and temperatures, the amount of payload, and the time-based costs that day. The time-based costs are especially dynamic, driven by the value of the payload and the schedule and operational constraints for the crew and the airplane. Winds can have a significant impact on the optimal route: it can be very far from the great circle "direct" route

One recent study by Boeing subsidiary Jeppesen considered the benefit of dynamic route optimization on an airline that used fixed company routes in its computer flight planning system. This airline, which had 60 single-aisle airplanes, used fixed routes developed with historical winds and experience about ATC requirements. The study determined that using routes optimized with the most recent forecast winds, with numerical constraints modeling ATC requirements, would save about 1 million U.S. gallons of fuel per year. This, in turn, would reduce annual CO2 emissions by about 20 million pounds.

Airlines can reduce fuel consumption and costs by improving the accuracy of their flight plans. The flight crew and dispatcher can elect to add fuel they think might be needed to complete the flight as planned. But the heavier the airplane, the more fuel it will burn, so adding extra fuel — which adds weight — burns more fuel, increasing both operating costs and emissions.

Accurate flight plan calculations can minimize the additional fuel the flight crew adds. Accurate calculations are the result of several factors that combine engineering and information management. Some of the relevant factors require integration with other systems and data sources, both within and outside an airline.

Airspace design and regulations are changing all the time, sometimes quite rapidly. Some recent innovations include continuous descent approaches, high-altitude redesign in the western United States, and new U.S. Federal Aviation Administration (FAA) extended-range twin-engine operational performance standards (ETOPS) rules. (Boeing can help operators make sure they're defining all of their ETOPS parameters and fuel analyses correctly.) These are in addition to less recent changes, such as the introduction of a reduced vertical separation minimum in different parts of the world.

However, not all operators can take advantage of the improvements right away because their flight planning software cannot be updated quickly enough. Those whose software is ready could take full advantage of the innovations, immediately reducing their fuel consumption and operating costs.