Cargo by Air

Air cargo is a broad term for anything carried on an aircraft other than passengers and their baggage, including commercial goods, mail and express packages. Air freight usually refers to commercial goods shipped by air, such as pallets, crates and machinery, as opposed to parcels and mail. In everyday use, many people treat the two terms as the same. For shippers, the practical distinction is between parcel services, which move small packages through hubs, and air freight services, which move larger shipments on flights with trucks at each end.

A ULD, or unit load device, is a standard aircraft pallet or container used to group cargo so it can be loaded and secured quickly. Pallets are flat platforms where cargo is stacked and held with nets and straps. Containers are enclosed boxes shaped to fit the aircraft's hold. Each aircraft type accepts specific ULD sizes in specific positions. Airlines and ground handlers build cargo onto ULDs at the airport, so shippers usually deliver their own pallets or crates, which are then placed onto the aircraft's ULDs.

Belly cargo flies in the lower holds of passenger aircraft, beneath the cabin. It benefits from the large number of passenger flights, but piece size and height are limited, and cargo must be screened and come from a known shipper. A freighter is an aircraft dedicated to cargo, with a main deck for large pallets and pieces. Freighters fly fewer routes but handle bigger, heavier cargo and some dangerous goods that cannot fly on passenger aircraft. Many shipments are booked on whichever fits the cargo and deadline.

An air waybill is the main shipping document for cargo moving by air. It acts as the contract between the shipper and the airline and as a receipt for the goods. It lists the shipper and consignee, the airports, the number of pieces, weight, dimensions and a description of the contents, along with any special handling instructions. Each air waybill has a unique number used to track the shipment. Unlike some ocean bills of lading, it is not a document of title and cannot be used to transfer ownership of the cargo.

When a freight forwarder consolidates several shippers' cargo into one larger shipment, the airline issues a master air waybill for the whole consolidation, naming the forwarder as shipper. The forwarder then issues a house air waybill to each individual shipper, describing that shipper's part of the load. The master covers the flight between airports, while each house air waybill covers the individual shipment. Both numbers can be used to track the cargo. Shipments booked directly with the airline, rather than consolidated, usually carry only one air waybill.

In the United States, all cargo carried on passenger aircraft must be screened under Transportation Security Administration rules before it is loaded. Screening can use X-ray, explosives trace detection, physical inspection or other approved methods. It may happen at the airline's terminal, at a certified screening facility before the cargo reaches the airport, or at a shipper's own certified facility. Companies that tender cargo to passenger airlines must follow TSA security programs. Accurate descriptions and packaging that can be inspected help screening go quickly and keep cargo on its planned flight.

A known shipper is a business whose identity has been verified under the Transportation Security Administration's air cargo security program. Cargo from a known shipper can be accepted on passenger aircraft, subject to screening, while cargo from an unknown shipper is generally limited to all-cargo aircraft. Known shipper status is managed by the airlines and by the companies that tender cargo to them. It matters to shippers because passenger flights offer many more departures than freighters, which can mean faster delivery and more options when a deadline is tight.

Dimensional weight is a calculated weight based on how much space a shipment takes up. For US domestic air cargo measured in inches and pounds, it is commonly found by multiplying length, width and height and dividing by 166. Airlines charge the greater of dimensional weight and actual weight, which is called chargeable weight. Light, bulky cargo is charged for the space it fills, while dense cargo is charged for what it weighs. Compact packaging and accurate measurements help keep the chargeable weight, and the cost, under control.

Recovery is the step where cargo is collected from the airline's terminal at the destination airport after the flight. Once the cargo has been unloaded and broken down from its ULD, the airline makes it available for pickup, and a truck or courier recovers it and takes it on for delivery. Recovery timing depends on how quickly the airline processes the arriving cargo and on terminal hours. For urgent shipments, having a truck ready at the destination airport as soon as the cargo is available saves valuable time.

A cargo-aircraft-only shipment contains dangerous goods that are allowed to fly only on freighters, not on passenger aircraft. Certain lithium batteries, flammable materials and other hazardous goods fall into this category under US hazardous materials rules and IATA regulations. These shipments must carry a cargo-aircraft-only label and be declared properly. Because freighters fly fewer routes than passenger aircraft, cargo-aircraft-only goods have fewer flight options, which can affect timing. A dedicated truck or an air charter is sometimes the better choice for them.

Airline liability for cargo loss or damage is limited, often to an amount per kilogram, which may cover only a fraction of the value of expensive goods. Cargo insurance is separate coverage that protects the full value of a shipment against loss or damage in transit. Shippers of high-value items, such as electronics, medical devices or machinery parts, often buy it for air shipments. The right coverage depends on the value of the goods, the route and any existing policies. Good packaging and accurate paperwork also reduce the chance of a claim.