The weight of an aircraft can affect its performance in several ways. Some airplanes are heavier than others. A standard Cessna 172, for instance, weighs about 1,669 pounds without any cargo or passengers. An Airbus A320, on the other hand, weighs over 82,000 pounds without any cargo or passengers. Here are several ways the weight of an airplane will affect its performance.
Takeoffs and Landings
Heavier airplanes require longer runways to take off and land. Commercial airports are typically equipped with long runways to accommodate heavy passenger airliners. Some of these runways are 8,000 feet long, whereas others are up to 13,000 feet long. Regardless, these long runways allow heavy passenger airliners to take off and land. Smaller airports, though, often have shorter runways that aren’t suited for heavy airliners.
Climb Rate
The weight of an airplane will affect its climb rate. Climb rate represents the speed at which an airplane gains altitude. It’s typically measured in feet per minute. The higher an airplane’s climb rate, the faster it will gain altitude. Heavy airplanes gain altitude more slowly than their lightweight counterparts, resulting in a lower climb rate.
Fuel Consumption
Another way in which weight affects airplanes is fuel consumption. Heavy airplanes must burn more fuel to generate and maintain lift when compared. This is why airlines carefully calculate the weight of airliners. If an airliner is loaded with passengers and cargo, it will require more fuel.
Stall Speed
The stall speed of an airplane will often vary depending on its weight. Stall speed is the minimum airspeed an airplane must fly to maintain level flight. If an airplane flies slower than its stall speed, it will experience a stall. It will lose lift and, thus, experience a drop in altitude. Heavy airplanes typically have a higher stall speed than lightweight airplanes, meaning they must fly faster to maintain level flight.
Forces of Flight
Weight will directly affect the forces of flight. The wings of an airplane, for example, must be able to generate lift that’s equal to or exceeds the airplane’s weight. Heavy airplanes often require large wings that are capable of generating high lift.
Heavy airplanes also require more thrust due to drag. Thrust comes from an airplane’s engine or engines. With heavy airplanes, there’s more drag acting against them. Therefore, they burn more fuel in an effort to counter this drag and generate lift.
