Generally, it is calculated based on the two data of payload and volume unit, for example:
The payload of Boeing 747 (-200~-400 models) is 20~25 tons (including pallets and bulk cabins), and the cargo hold volume is 170~175 cubic meters.
The payload of Boeing 767 (-200~400) is 12~15 tons (including pallets and bulk cabins), and the cargo hold volume is 99.2~110 cubic meters.
The payload of Boeing 777 (-200~-300) is 20~25 tons (including pallets and bulk cabins), and the cargo hold volume is about 132 cubic meters.
In addition, the number of pallets that various models can carry is also different, for example:
Boeing 747-200 can carry 7 pallets/9 boxes;
Boeing 747-300 can carry 15 pallets/2 boxes.
Boeing 747-400 can carry 7 pallets/16 boxes.
Usually, the front cabin of a large passenger aircraft is loaded with pallets, and the rear cabin is loaded with boxes. The front cabin's pallets can also be exchanged for boxes, and the bulk cabin is located at the aircraft's tail. Large pallets can load 2.5 tons, small pallets can load 2.3 tons, and less can be loaded when the load is limited. Large boxes are 0.8 tons, and small boxes are 0.6 tons.
Pallets include PEB, PGA, PLA and other specifications. It is a flat aluminum plate on which goods can be placed and fixed by a net rope. The container type is AKE, the ATA code is LD3, and the body weight is 66 kg. With the prosperity of air transportation, there is another type of aircraft that people usually don't come into contact with - all-cargo aircraft. For example, the largest aircraft now is the An-225 and the most advanced all-cargo aircraft Boeing 747-8F. International logistics giants have a large fleet of all-cargo aircraft. For example, FedEx has as many as 638 all-cargo aircraft, including 50 Boeing 767-300F and 30 Boeing 777F. Since most of the costs of operating a passenger aircraft can be spread out through passenger operations (such as flight, crew, landing and takeoff fees, and air services), the belly cargo of a passenger aircraft has a higher profit margin of 65%. In the early years, the International Air Transport Association predicted that the total cargo volume of all-cargo aircraft would decline to 30%, which shows the importance of the belly cargo of passenger aircraft.