When an aircraft designer is choosing a wing, they not only have to take into consideration the aerodynamic factors but also the cost of manufacturing, weight, and maintainability. Manufacturers have assorted budgets and design aircraft with different operating requirements, so they have to weigh the pros and cons of opposing factors. For example, a defense aircraft will focus more on speed and maneuverability, while airliners will focus more on range, comfort, and efficiency. Airliners can utilize higher aspect ratios— span divided by the mean chord— to increase lift and support higher loads; however, fighters will have lower aspect ratios to reduce drag and increase maneuverability. As such, when choosing the optimal aircraft wing, an engineer must consider a few factors such as airfoil selection, wing planform, and wing configuration.