Calculate Aircraft Payload
Aircraft are used for recreation, news and traffic reporting, fire fighting, construction, rescue operations, medical emergencies and military applications. Aircraft also are used to move people and cargo from place to place. Aircraft suffer a performance penalty for every pound of weight that they lift. Much of this weight to be lifted is an unavoidable part of making flight possible. These unavoidable weights include the airframe, the engines, a large quantity of fuel, and the aircraft crew. Any weight over and above these unavoidable weights can be used to transport customers and ship goods for customers. These extra weights represent the load on the aircraft that a customer is paying for, from which the term payload originated. The more payload that can be lifted and the farther it can be carried, the more the company operating the aircraft can charge customers. Only so much payload can be lifted, and the payload weight detracts from the operating range of the aircraft. Use these tips to learn how to calculate aircraft payload.
Steps
- Get the manufacturer's data for the aircraft. This data will list the following important parameters of the aircraft:
- Check the standard weight empty of the aircraft. The standard weight empty will indicate the weight of the aircraft with no fuel, passengers or payload on board.
- Find the maximum gross weight of the aircraft. The maximum gross weight is the upper limit of weight that the aircraft may be loaded to without structural damage.
- Look up the maximum takeoff weight. The maximum takeoff weight is the most that the aircraft can weigh during take off.
- Determine the maximum landing weight. The maximum landing weight is the most that the aircraft can weigh during landing without risking damage to the landing gear.
- Note the fuel capacity of the aircraft. The fuel capacity will be listed in either U.S gallons or Imperial gallons.
- Calculate the weight of fuel carried. The fuel tanks may not be loaded to capacity, so use the weight of only the fuel known to be added. Calculate the weight as 6 lbs. per U.S. gallon (2.72 kg per 3.79 L) or 7.2 lbs per Imperial gallon (3.23 kg per 4.72L) if the fuel used is aviation gas. Calculate the weight as 6.6 lbs per U.S. gallon (3.0 kg per 3.79 L) or 8.0 lbs per Imperial gallon (3.6 kg per 4.72 L) if the fuel used is JP-4.
- Determine the maximum payload. The maximum payload is the difference between the standard weight empty plus the weight of fuel carried, and either the maximum gross weight or the maximum takeoff weight, whichever is less. In almost every case, the maximum takeoff weight will be less and should be used for the calculation.
- Divide the payload between people and cargo.
- Count the aircraft crew as people. If known, the actual weight should be used. If the actual weights of the crew are not known, estimate the weights as 174 lbs. (79.0 kg) per male and 127 lbs. (57.6 kg) per female. Add 8 lbs. (3.6 kg) to each crew member weight for summer clothing and 14 lbs. (6.4 kg) per crew member for winter clothing.
- Add the passenger weights. Count each male passenger as 174 lbs. (79.0 kg), each female passenger as 127 lbs. (57.6 kg), and each child as 75 lbs. (34.0 kg). Add 8 lbs. (3.6 kg) to each adult for summer clothing and 14 lbs. (6.4 kg) for each adult for winter clothing. Use 75 lbs. (34.0 kg) per child without adding an additional factor for clothing weight.
- Subtract the crew and passenger weights from the payload. The resulting calculated weight is available for baggage and cargo. Do not consider the volume of the aircraft to carry luggage and cargo. The weight limits will be reached before the aircraft runs out of space to hold the cargo.
- Take maximum landing weight into account. The maximum landing weight will be less than the maximum takeoff weight. The aircraft must have consumed enough fuel at the manufacturer's fuel consumption per thrust rate to reduce the total aircraft weight below the maximum landing weight before a landing can be made. If emergency conditions require an early landing, fuel or cargo (but not passengers) must be jettisoned to reduce the weight of the aircraft to the maximum landing weight.
