Part V — Air & Multimodal
Air Freight Forwarding
How cargo moves by air — aircraft and ULDs, the Air Waybill, the rate structure (N-rate, quantity and commodity rates), the players from airline to IATA agent, and AOG, the most urgent cargo of all.
Air freight is the fast, premium mode — chosen for what is urgent, valuable, perishable or bulky-but-light. NAFL traces its origin neatly: air cargo grew as an offshoot of passenger travel, filling the hold space left over once passengers and baggage were loaded. Understanding that origin explains much about how air freight is priced and sold.
Why there is space for cargo at all
Because an aircraft fuselage is oval, not square, and because passengers and baggage take priority, only the leftover capacity is available for cargo. NAFL works it through a Boeing 737-400: with a full passenger load, only about 3–6 tonnes (≈15% of the aircraft’s weight/volume capacity) is left for freight — unless the aircraft flies as a pure freighter. Airlines therefore chase the right mix of passengers, mail and cargo to maximise margin.
How cargo is carried
- Belly freight — cargo in the lower hold of a passenger aircraft, under the seating deck.
- Freighter — an all-cargo aircraft; cargo on the main deck (in ULDs) plus lower holds. Can be nose-loading (e.g. 747F) or side-door.
- Combi — a single main deck split between passenger seats (front) and ULD cargo (rear); common on Europe–Dubai routes in NAFL’s era.
Unit Load Devices (ULDs) and pallets
A Unit Load Device (ULD) is a standard pallet or container built to fit the contoured holds of wide-bodied aircraft. ULDs let cargo be pre-built and checked well before departure, speed loading, protect cargo from weather and pilferage, and (in temperature-controlled versions) hold an internal climate. Their uniform specifications are what make aircraft loading fast and precise.
Cargo is built onto ULD pallets (secured under nets) or into ULD containers shaped to the aircraft’s cross-section. Acceptance always checks four things NAFL lists: does the aircraft fit the cargo (space)? will it pass through the door? can the floor take the weight? is the nature of the goods acceptable (dangerous goods)?
The Air Waybill (AWB)
The governing document of air freight (introduced in Chapter 8). NAFL lists its functions:
- a contract between shipper and issuing airline;
- a description of the goods (weight, volume, nature);
- the agreed routing, origin airport to destination;
- identification of shipper and consignee;
- the freight charge calculation;
- a record of other charges and declared value;
- a receipt for the goods.
It is issued in three originals — for the carrier (green), the consignee (red) and the shipper (blue) — and must be signed/stamped by both carrier and shipper. Crucially, the AWB is not a document of title and is non-negotiable (unlike the ocean B/L). Air carriage law: the Warsaw Convention (1929), amended by the Hague Protocol (1955) — today superseded by the Montreal Convention (1999).
Where one airline carries another’s cargo (no service to the origin), an interline agreement applies, and carriers are named First Carrier, Second Carrier etc. along the route.
Air freight rates
Air pricing has traditionally been built on route + weight/volume, with rates filed with IATA and governments. NAFL’s rate structure:
| Rate | Meaning |
|---|---|
| N-rate (Normal) | the basic rate per kg (1 kg / 6,000 cm³) regardless of commodity |
| Q45 (Quantity) | at 45 kg, a ~25% discount on the N-rate, to encourage larger shipments |
| M-rate (Minimum) | an absolute minimum charge (≈ 5 × N-rate) for very small consignments |
| Higher weight breaks | Q100, Q300, Q500… progressively lower rates for heavier consignments |
| Commodity rates | special rates for specific commodities, weight breaks and origins (e.g. textiles min 200 kg) |
The market is segmented by shipment size — minimum / normal / Q45 / Q100 / Q300 / consolidations. And recall the 1:6 ratio (Chapter 3): the agent’s craft is to consolidate the right mix of dense and bulky cargo to get close to 1 CBM = 167 kg and maximise margin on the generous air weight/volume allowance.
The players in air cargo
- Airline categories NAFL distinguishes: the value-adder (expands services — customs, packing, IT, pickup/delivery), the commodity seller (sells spare capacity through intermediaries), the “innocents” (passenger airlines discovering cargo), the national carriers (state-owned, trade-facilitating), and the integrators/express operators (forwarder + carrier with their own aircraft — DHL, FedEx, UPS).
- GSA (General Sales Agent) — represents an airline’s cargo (and/or passenger) sales in an area, sparing the airline its own full infrastructure; may add value through trucking or distribution networks.
- IATA Cargo Agent — a forwarder registered and accredited by IATA, meeting criteria on trained (DG-licensed) staff, premises, clean record, unique trading name, trade licence, finances and insurance. Accredited agents settle with airlines through CASS (the Cargo Accounts Settlement System), a central clearing house that nets all the agent’s airline billings into one periodic payment — which is what lets an accredited forwarder (like WorldZone) book airline space directly and at agent rates, including on short notice for AOG (above).
AOG — when the cargo simply cannot wait
The most time-critical cargo in the whole industry is the aircraft spare part, because a grounded aircraft is one of the most expensive idle assets in business.
AOG stands for Aircraft On Ground — an aircraft unable to fly until a specific part is fitted. The term has become the label for the highest-priority air-freight service tier: the emergency movement of aircraft spares (and the tools/components to fit them) to get a grounded aircraft back in the air. Every hour an airliner sits grounded can cost its operator tens of thousands of dollars in lost revenue, missed slots, crew and re-accommodated passengers — so on an AOG shipment speed beats cost, always.
How an AOG move differs from ordinary air freight:
- 24/7/365 response. AOG desks never close; a request at 3 a.m. is actioned immediately — the opposite of a normal booking that waits for office hours.
- Whatever it takes to move it fastest. Next available flight regardless of price; an On-Board Courier (OBC / hand-carry) who flies with the part as cabin baggage when no suitable cargo flight exists; or, for a critical engine/landing-gear part, a dedicated charter. Cost is secondary to the next departure.
- Pre-cleared and expedited. Documentation, customs and airline acceptance are pushed through ahead of the cargo; an AOG label gets priority handling at every touchpoint.
- Often dangerous goods. Many aircraft parts are hidden DG — chemical oxygen generators, evacuation-slide cartridges, fire bottles, lithium batteries, fuel-wetted units — so AOG and dangerous-goods discipline (Chapter 21) go together: certified staff, correct declaration, no shortcuts even under time pressure.
- Priced at a premium. AOG rates sit well above standard air rates, and the customer accepts it, because the freight cost is trivial against the cost of the grounded aircraft.
A related tier you will hear alongside it is “critical” / “time-critical” / next-flight-out (NFO) cargo — the same emergency-logistics discipline applied to any shipment (not just aviation) where a production line or a contract is about to stop for want of a part.
AOG is the urgent extreme of spare parts — one of WorldZone’s five core cargo types (Chapter 30). Most spare-parts traffic moves on normal air or sea-air (Chapter 20) to balance speed and cost; AOG is what happens when the clock is absolute and only the next flight out will do. The operator’s job on an AOG enquiry is to think in minutes, not days: find the fastest routing (cargo flight, OBC, or charter), pre-clear the paperwork, screen for hidden dangerous goods, and quote the premium plainly — the customer is buying speed, and knows it.
The biggest change is the rate world. NAFL’s IATA-filed, government-approved tariffs have largely given way to market-driven, dynamic pricing — capacity and demand set the price, booked increasingly through digital platforms and APIs (and e-AWB, the electronic air waybill, now standard). The integrators NAFL lists as a rising segment are now dominant global forces. And air DG has tightened: the IATA Dangerous Goods Regulations are updated annually with mandatory recurrent training (Chapter 21). The Montreal Convention has replaced Warsaw for liability. The structure NAFL teaches — N-rate logic, weight breaks, the 1:6 consolidation play — still explains how the market thinks.
Air Freight Forwarding is one of WorldZone’s core services, and the decision of when to use it is the skill — for small, bulky, high-value or urgent cargo where the 1:6 ratio makes air competitive with sea (Chapter 9). An operator quoting air must run the chargeable weight (Chapter 3), check the four acceptance tests, prepare a clean AWB, and — for consolidations — build the dense/bulky mix that earns margin on the weight/volume allowance. Sea-air combinations (next chapter) are a WorldZone-relevant middle path: much of air’s speed at much less than air’s cost.
What to take from this chapter
- Air cargo rides mostly in belly space; freighters and combis add main-deck capacity via ULDs.
- The AWB is contract + receipt + description, non-negotiable and not a document of title; law = Warsaw/Hague → Montreal.
- Rates build from the N-rate with quantity (Q45+) and commodity discounts; the 1:6 ratio drives consolidation margin.
- Know the players: airline types, GSA, IATA cargo agent, integrators.
- AOG (Aircraft On Ground) is the highest-priority tier — emergency aircraft spares where speed beats cost: next flight out, on-board courier or charter, pre-cleared, often dangerous goods.