Air transport is by far the most time efficient mode of transporting goods, and in humanitarian contexts is used both domestically and internationally. Unfortunately, along with the speed and efficiency of air transport comes significantly higher costs and far more restrictions and complexities on handling of goods. In emergencies, and especially natural disasters and conflict situations where road access is difficult, air transport is often the preferred alternative.

Common Terms in Air Transport

Fixed wing

The most common type of aircraft – any airborne vessel with wings that requires horizontal take-off and landing space.

Rotor wing

Helicopters of any configuration that have top mounted rotors to provide vertical lift, and have vertical take-off and landing capability.

Civil Aviation Authority (CAA)

Any authority that maintains legal jurisdiction over the airspace above any country. Aircraft operating within a country or flying over a country (overflight clearance) must make arrangements through CAAs.

International Aviation and Transportation Administration (IATA)

An international governing body that sets safety regulations on commercial flight. Any aircraft commercially operating between two different countries that mutually recognize IATA standards is legally obliged to follow IATA regulations.

Tech Stop

Used to describe a situation when an aircraft must be on the ground for technical reasons. Usually tech stops refer to refuelling, but they can also be for unscheduled maintenance. Sometimes referred to as “going technical.”


Where the “permanent” home of the aircraft is, usually where the aircraft is originally licensed, and near the owner and operator. Domicile location are also frequently where aircraft receive routine maintenance as well, but not always.


Moving an aircraft from one location to another location in anticipation of another future need.

Ground Support Equipment

Any equipment involving the offloading or moving of cargo around an airport or landing strip, in lead up to loading or offloading cargo and people. Ground handling crews can be employees of governments, or sub contracted service providers.

Cube/Weigh Out

The act of reaching the maximum limitations to a specific airframe, either by reaching its maximum volume (cube out) or its maximum weight (weigh out).

Flight Hours

Defined as the specified hours air craft, pilot or crew are allowed to operate for. Physical air craft may only be able to operate for a maximum number of hours in any week or month period, while pilots and crew can only operate for a maximum number of hours per day/week before mandated “crew rest.”


All the special considerations surrounding aircraft loading, such as:

  • Deck cargo – cargo loaded onto the main deck/body of an aircraft
  • Belly load – cargo loaded unto the under deck/belly of an aircraft
  • Nose load – cargo loaded into the front compartment of an aircraft
  • Tail load – cargo loaded into the rear compartment/are past the real wheel based of an aircraft
  • Door dimensions – dimensions to all points of entrance to an airframe that define maximum size
  • Load balance - loading cargo onto a plane in a way that maximizes safety and energy
  • Loadmaster – the duly certified person ultimately responsible for determining how and what gets loaded onto a plane

Dangerous Goods (DG)

Any cargo that might post a threat to aircraft while in transit or loading/offloading. DG is universal to all forms of transport, but is especially important to air aviation. Definitions, handling and labelling standards for DG are outlined in the IATA Dangerous Goods Regulation (DGR).

Sling Loading

The act of transporting cargo on the outside of a rotor wing aircraft using a net or cable of some kind, with cargo hanging below the aircraft. Sling loading requires special equipment and specially trained pilot and crew, and can only be used in some ideal circumstances.

Air Transport Arrangements

The nature and type of the arrangements humanitarian agencies enter into for the movement of cargo by air will be largely informed by the volume of goods, type of goods and shipping/destination points. Most medium sized cargo loads (1-20 full pallets / 30 cubic meters) shipped internationally will generally not require a specialized flight, while a high volume of cargo (500+ full pallets / 700 cubic meters) might require obtaining a full plane. Conversely, extended, routine operation inside the borders of a country no matter how small might require long term leasing of an aircraft.

In almost all situations, different arrangements for air cargo transport will need to be arranged by forwarders, brokers, or other third-parties who have the ability to connect requestors to various available options. Regular movement of small cargo can be done through a typical freight forwarder, while specialized charters or leases may be done through specialized brokerages. Agencies acquiring these arrangements will need to go through their typical procurement process.

Typical air transport arrangements can look like:

Regular scheduled – Air carriers around the world develop regular routes between high volume or common destinations. Cargo traveling on regularly scheduled movement is similar to buying a seat on a regular passenger plane – it’s easy to identify space and move cargo because the movement is predictable and frequent. Cargo shipped along regularly scheduled routes can be moved as excess cargo in the hold of a commercial passenger plane, or transported using regularly scheduled cargo planes. Often, cargo moved along regularly scheduled routes will be broken up into multiple tranches and reconsolidated on the receiving end, a process that is enabled by the predictability of arriving flights. Regular movement by air is cheaper than organizing special flights. Unfortunately, regular scheduled flights will not deviate from their courses, and tend to only serve more developed markets. 

Charters – Many forwarders and air carrier specialize in organizing charter flights – flights specifically dedicated to the movement of one or a very few consignments. Charter flights are often extremely expensive, but have the advantage of being able to depart from a specified origin, arrive at a specified destination, and meet the size and airframe requirements of the proposed air movement. A properly arranged charter might be able to match the size of the aircraft to the requested cargo size saving on total costs, as well as identify special needs such as the overall operating environment or limitations on size of aircraft. Unfortunately, charting aircraft frequently means repositioning an aircraft from another area as the exact airframe may not be domiciled at the desired point of departure. This means that users of charter services usually have to pay for repositioning costs. As charters are basically only single aircraft, shippers run the risk of technical defaults holding up the entire process as well. Factors that influence the decision to charter and the nature of the aircraft chartered:

Aircraft Leasing – In situations where long term, well identified needs are in place, organizations may choose to lease aircraft. Aircraft can be leased for months or years at a time, and leased aircraft can be used on an ongoing basis for needs as they evolve. A “Dry Lease” is when an aircraft is made available to an agency without additional support of crew or maintenance, while a “Wet Lease” is a lease type that includes pilots, crew, and aircraft maintenance. Wet leases are more expensive, especially because teams are paid at a commercial rate and because food and housing is usually part of the contact, but many agencies prefer wet leases due to the fact they take the complexity of aircraft management out of the hands of non-aviation experts. 

Other arrangements – During times of emergency, air cargo may be transported through a variety ad-hoc or irregular means. This might include cargo movement on military air craft, in personally owned air craft, or agencies offering free space to each other. The process of utilizing non-traditional air transport to move cargo can have varied procedures and tolerance thresholds. Irrespective of the movement type, users will have to respect CAA and national import regulations at all times. 

Unique Components to Air Transport

Air transport has become so common in the modern world that shippers frequently take key important factors for granted, or overlook them when planning and utilizing aviation for cargo. Understanding some of these unique needs will help when planning large international shipments, but will also help understanding in-country and response specific aviation needs as well.

Weight as a limiting factor

In all aviation, one of the largest factors that impact speed and price is the overall weight of the airframe and its contents. In cargo operations, the take-off weight of an airframe in flight can vary substantially – an airframe fully loaded with heavy cargo easily double the total weight of the same aircraft without cargo. All aircraft have what is known as a “maximum take-off weight” – or the maximum weight at which an aircraft can safely take off and reach the desired altitude and flight path. This weight is calculated as a combination of the physical aircraft, cargo, passengers, and fuel. The maximum take-off weight can also be impacted by outside conditions, such as the wind direction, ambient temperature or the length of a landing strip. Pilots and loadmasters have ultimate discretion for the safety of their aircraft and crew, and will make the final calculations on what is safe and achievable for an aircraft, and what is not.

Based on the aforementioned factors, the acceptable weight of the payload may fluctuate, changing costs and overall delivery schedules. For this reason, light but voluminous cargo might always be able to fill up an entire cargo hold – or “Cubing out” by reaching the maximum available load through volume – while more dense and bulky cargo might be able to take a relatively small portion of a cargo hold – or “weighing out” by reaching the maximum lift weight. The orientation of a cargo inside of an aircraft is also very important, and loadmasters and crews will need to properly place and balance loads to maximize aircraft safety while taking off, flying and landing.

Fuel as a limiting factor

Aircrafts consume relatively large amounts of fuel per kg compared to other transport methods, and unlike other modes of transport, stopping to undergo refuelling is a complicated process. Whereas a boat or vehicle running out of fuel in mid-movement might strand a vehicle or leave it adrift, an aircraft running out of fuel has immediate and tragic consequences. In aviation, fuel calculations are estimated per flight, based on range, altitude, cargo load, wind conditions, and if the airport of arrival has refuelling capabilities. In real terms, there are many factors that might make travel over the same distance consume more or less fuel than it would in a similar route. An increase in the take-off and carriage weight increases fuel used per km, while flying into a prevailing wind-current will also increase fuel consumed per km. Knowing this, crews will increase the fuel in their tanks, which might adversely affect maximum take-off weight. In other words, the cost for kg of cargo might go up, while the total quantity of kg you can ship might go down.

Prevailing conditions as a limiting factor

Aircraft – though highly engineered pieces of equipment – can still be heavily impacted by the physical environment. In addition to factors that can be controlled by the crew and pilots (such as load and maintenance) some external factors that might impact an aircraft’s ability to operate safely are:

Airport facilities as a limiting factor

Though aircraft may be able to physically fly to a destination, they may not be able to adequately service the cargo needs.  Limiting factors might include:

Regulations as a limiting factor

Local and internationally recognized regulations may impede cargo operations by limiting or preventing aircraft from operating all together.  Some of these regulatory factors might include:

Sending Goods by Air

Air transport documentation

The overall requirements for and types of documentation used for air transport depend on the nature of the air transport. The normal documentation requirements for most shipments (waybill, packing list, proforma, etc) applies to all shipments, including air shipments. There are documents specific to air shipping however. These might include:

Airway Bills (AWB) - By far the most common and important document related to airfreight. AWBs are regulated by IATA, and have a standard format for ease of reading and reference. It should be noted that AWBs are only legally required for international transport, however domestic CAA and even non officially regulated air carriers can and do request the use of AWBs. The AWB is the carrier’s receipt by air, evidence of the contract of carriage and is usually non-negotiable. It is made out to a named consignee who is the only party to whom the carrier can deliver. Many carriers even make it easy to track and trace cargo in real time using AWB numbers on their website. Through its standardized layout, AWBs will denote:

The above information should match the information coming on other shipper generated shipping documents. In the top right corner of every official AWB, there will be an AWB number, which is unique to that one AWB. The AWB number is always eleven digits; the first three are the IATA designated airline prefix, while the last seven digits are the unique serial number. Many airlines make AWB numbers easy to trace online.

Original, airline generated AWBs are generally the only acceptable AWBs that customs authorities will recognize. The original paper copy will go with the consignment, but scanned copies are usually acceptable for customs purposes. The AWB generated by the airline is typically referred to as the “Master” AWB, or sometimes MAWB.

Example AWB:

House AWB – A “House” AWB – sometimes referred to as a HAWB - is generated by a forwarder or broker and provided to a client upon request. HAWBs generally have all the same information as a regular AWB, but are not necessarily signed or have the same tracking information as the MAWB. Customs authorities generally do not recognize HAWBs as an official document for customs procedures as there may be some difference between the HAWB and the MAWB. HAWB may still be useful for internal tracking purposes, however.

Non-Standard Waybills – In emergency settings, especially when in-country movement is required via air, the AWB may not be applicable or available. Cargo moved via unconventional air movement will generally always require some form of documentation, however this may look like a stand-alone packing list, self-made cargo manifest (similar to a packing list), or in the case of movement on military assets, a standard form internal to that specific military.

Shippers Declaration of Hazardous Goods (HazDec) – Much like AWBs, HazDecs are predefined by IATA, and are essential to the shipping process. HazDecs contain relevant information on any and all DG items for loadmasters and pilots. Any airline following IATA regulations will not accept a completed HazDec unless it was filled out and signed by someone who is fully certified in DG handling through an IATA accredited program. Failure to comply with proper completion of a HazDec, or incidents that may occur from incorrectly documented DG can result in fines, court action and jail time.

Blank HazDec:

Cargo Configuration for Aircraft

Cargo shipped via air tends to require more attention to details.  Unlike the inside of a standard shipping container or regular box truck, the inside of aircraft tends to be irregularly shaped. Fixed wing aircraft – especially fixed wing aircraft that operate at high altitude – will have curved cylindrical interiors, while larger aircraft my have multiple decks of varying heights. Additionally, the width and height of interior cargo holds and doors is different for virtually every aircraft. Frequently, more than one aircraft will be used for multiple legs of a transport route, meaning pallets can be broken down and cargo reloaded multiple times to match the different types of aircraft. This tends to lead to cargo being broken down and reconsolidated extensively throughout the transport process.

To accommodate the variance in the size needs for different airframes, cargo shipped via air tends to be “loose-loaded,” being loaded at the lowest handling unit (carton, sack, etc), so that handling crews can maximize space and shape cargo builds to fit the interior of the available cargo space. Oversized cargo, or premade pallets that don’t fit the specific dimensions of the airframe in question will either not be loaded, or will need to be broken down into smaller units for loading.

Unit Load Devices - Many aircraft will utilize what are known as “Unit Load Devices,” (ULD) or pre-made containers that facilitate the easy transport of cargo via air. Each airframe has its own specific dimensions of UDL which are used internally by the air carriers and won’t be the responsibility of the shipping party to obtain or manage. UDLs require the assistance of MHE or other vehicles to move and load, and are usually managed out of larger professional airport with trained ground crew.  Understanding UDLs can help transport planning for shippers.

Some aircraft will load cargo on a type of UDL called an “airplane pallet” – the pallets thin sheets of metal that can be easily moved on rollers, and are much larger than warehouse pallets. Cargo will be loaded loose on the pallet pre-shaped to match the interior of the specific aircraft in question, and will be covered in cargo netting. 

Example airplane pallet and netting:

Larger and mixed-use aircraft will often use a form of UDL called a “contoured container.” Contour containers are sold containers with one or more rigid sides that are pre-shaped to match specific compartments inside of an aircraft. The containers are made of extremely thin metal, and are designed to take the guess work out of space planning. There are a variety of contour containers, including partially open containers, refrigerated containers, etc. The use of these specific variations will be decided by the airline and the load master based on the needs of the shipper.

Example contoured container:

Hand Loading – Aircraft used in smaller or irregular flights are often loose loaded by hand. This entails loaders and crew manually loading items into a cargo hold at the handling unit level, stacking and stuffing where ever space is available, and where ever is safe or appropriate. Aircraft used in humanitarian operations at the domestic level frequently use handloading due to lack of equipment and aircraft type. Hand loading aircraft has limitations, including requiring additional time to complete and being less secure than netted cargo, but is useful insofar as it can be done in almost any environment and under almost any condition.

Packaging and Labeling

Packaging and labeling for air transport is an important consideration. Knowing that cargo is often broken down or shipped loose means that shippers must adequately mark cartons to facilitate tracking of cargo transported by air. It is strongly advised that all cargo intended for air transport be labelled at the level of the carton or handling unit, and should have some - if not all - of the corresponding data:

Properly labelled packages will help reduce loss while in transit. Professional freight forwarding services tend to be extremely good at keeping large consignments together throughout the course of an air movement. Frequently, large consignments will be split into multiple smaller consignments, and will be reconsolidated prior to delivery. In emergencies however, movement can be chaotic and cargo frequently delayed or lost. The more visible and easily identifiable relief cargo is, the more likely it is to reach its final destination.

Dangerous Goods – Danger Goods (DG) has special packaging and labelling requirements. IATA continually publishes an updated guide for DG packaging and labelling for air transport. Dangerous goods of different classification will need to be labelled with the appropriate and corresponding label.  Additionally, IATA and other safety guidelines may stipulate the maximum size and quantities of certain DG items that can be transported, and will stipulate any required “overpacking,” or an additional layer of packaging over the handling unit packaging. Packaging and labelling standards for cargo should be overseen by persons who are properly certified and accredited through an IATA approved DG certifier program.