Air cargo's empty half: The problem more freighters can't fix

Every year, as peak season nears, air cargo capacity becomes the industry's dominant conversation. Airlines add flights. Forwarders scramble for space. Rates climb, sometimes overnight, and shippers watch anxiously to see whether their goods will make it onto a flight in time for the rush. Warehouses fill up. Phones do not stop ringing. For a few frantic weeks, every conversation in the business comes back to the same worry: is there enough space in the sky?

But underneath that noise sits a quieter problem, one that rarely makes headlines, yet shapes prices and planning far more than most shippers realise.

It is called the backhaul problem. And it starts with a simple question: what happens to the empty side of the aircraft?

A flight rarely balances both ways
An aircraft that flies from Shanghai to Chicago packed with goods must still make the journey back. That outbound leg, the one with strong demand, is what the industry calls the headhaul. The return leg is the backhaul, and if there is little cargo wanting to travel from Chicago to Shanghai, it flies with empty space. The airline still pays for fuel, crew and airport charges on that return journey. Someone has to cover that cost, and it usually gets folded into the price of the outbound leg.

This is not a new problem. A study published in the Journal of the Air Transport Research Society, by researchers Vincent Van Bockstaele, Sven Buyle and Wouter Dewulf, describes it plainly: load factor, which is simply how full a flight is as a percentage of its available cargo space, sits far higher on dedicated freighters, at around 65%, compared with only around 36% on passenger aircraft carrying cargo in their belly, according to IATA figures cited in the study. Passenger flights are booked mainly around people, not cargo, so the mismatch between one direction and the other tends to be sharper.

The instinct is to picture this as a clean, worldwide pattern: strong outbound demand, weak return flow, everywhere, all the time. But the people actually managing cargo on the ground say the picture is messier than that.

The picture is not one imbalance. It is many
Kathy Liu,VP, Global Sales & Marketing at Dimerco Express Group, the freight forwarder, put it simply.

"The imbalance therefore varies by origin, destination and commodity rather than following the same headhaul-backhaul pattern across all routes," she said.

Her point is worth sitting with. Taiwan to the United States remains tight, driven by semiconductors and AI-related hardware. South Korea reports strong load factors in the same general direction. Malaysia, Thailand and Singapore also remain relatively tight on selected lanes. But China and Hong Kong exports to the US have softened, easing pressure on that corridor even as its neighbours stay stretched. And in the opposite direction, some routes from the US into Asia are tight too, which is not what the classic headhaul-backhaul story would predict.

In other words, there is no single dial marked "strong outbound, weak return" that applies everywhere. It shifts lane by lane, and commodity by commodity, almost market by market within the same region. A forwarder planning capacity across Asia this season cannot use one playbook. Taiwan behaves nothing like Hong Kong. Korea behaves nothing like Thailand.

Data from TAC Index backs this up from the pricing side. Neil Wilson, the Editor at TAC Index, described two very different stories playing out at the same time. Rates from China to Europe are up around 12% year-on-year, but only after a slower period. Volumes and rates on that lane dropped following the end of the European Union's de minimis exemption on 1 July, a regulatory change that reduced the flow of low-value parcels, and the lane has only recently begun to stabilise. Rates from China to the United States, meanwhile, are up around 30% year-on-year, a much sharper rise. Wilson linked this to continuing demand from the AI sector, semiconductors, and steady e-commerce volumes.

Two very different rate stories, on two lanes out of the same country, in the same season. That is the fragmented imbalance Liu described, showing up directly in the price data.

There is a cost layer sitting underneath all of this too. Rising jet fuel prices, driven by tensions in the Persian Gulf and disruption through the Strait of Hormuz, are pushing costs up across the board, even on lanes where demand has cooled. Rates, in other words, are not only a story about how much cargo wants to move. They are also a story about what it costs to fly the aircraft in the first place.

What a real imbalance looks like on the ground
Numbers on a lane are one thing. Seeing the imbalance play out at a single airport is another.

Velana International Airport (MLE) in the Maldives is a useful example, because its imbalance is not seasonal or lane-specific. It is structural, built into the shape of the country's economy.

"MLE has a structural imbalance toward inbound cargo, reflecting the Maldives' import-dependent economy and the role of tourism as the country's primary economic driver," said Hussain Shafiu, Manager, Cargo Development, Commercial at Velana.

The Maldives imports far more than it exports. Food, consumer goods, e-commerce parcels and tourism-linked supplies flow in constantly. Outbound cargo, by comparison, is thin, and much of what does leave is transshipment cargo, passing through the Maldives rather than originating there.

This is where the story becomes more than an academic curiosity. An airport with a heavy inbound skew still needs a plan for its emptier, outbound side. Shafiu explained that Velana has leaned into its position as a transshipment gateway in the Indian Ocean, prioritising fast connections over storage for cargo simply passing through.

MLE opened a new cargo terminal in 2024, built to handle up to 120,000 tonnes a year. The airport handled close to 89,000 tonnes of cargo in 2025, with peak-day volumes during the December holiday period reaching around 380 tonnes. Daily throughput now regularly passes 200 tonnes, with peak days exceeding 300 tonnes. Winter 2026/27 will bring a 12% rise in flight movements, along with new freighter connections including Raya Airways' weekly Penang-MLE service.

During the holiday season specifically, Velana increases belly capacity, meaning cargo space in the hold of a passenger aircraft rather than a dedicated freighter, on flights to Europe, deliberately creating more space for shippers to use on what would otherwise be a quieter route.

The bottleneck is rarely the aircraft itself
Ask anyone at an airport what actually slows cargo down during the holiday rush, and the answer is rarely the aircraft. It is far more likely to be what happens once that aircraft has landed.

At Velana, warehouse capacity and manpower deployment have historically been the biggest constraints during holiday peaks, not the number of flights arriving. Cargo can sit on an aircraft for a matter of hours, but it can sit in a warehouse for far longer if there are not enough hands and enough space to process it. That new terminal, opened in 2024, was built specifically to address this, running 24 hours a day and designed to absorb seasonal surges without the congestion the airport used to see.

Historically, warehouse capacity and manpower deployment have been the main constraints during holiday peaks
Hussain Shafiu, Velana

Coordination matters just as much as physical space. Velana works closely with airlines, forwarders and agents to forecast expected cargo volumes, flight schedules and cargo flows well before a known peak period arrives, so manpower and handling support can be aligned with demand rather than scrambled together at the last minute. The airport's round-the-clock operation also gives it room to sequence cargo more cleverly. Sea-to-air cargo, for instance, can be processed during off-peak hours in coordination with the Maldives Ports and Customs, keeping that traffic away from the busiest congestion windows. Because so many passenger airlines connect through Velana in the early morning, the airport also works with carriers to make better use of evening operating windows, spreading pressure across the day rather than letting it land in one narrow window.

None of this shows up as a headline capacity number. But it is exactly the sort of unglamorous groundwork that decides whether a shipper's cargo actually clears in time for the holidays, or sits waiting for space that technically exists but cannot yet be reached.

How forwarders route around the gap
Forwarders do not simply wait for imbalance to resolve itself. They adjust behaviour to manage the risk.

Liu described several patterns Dimerco has observed this year. Earlier tariff-related front-loading pulled some shipments forward, ahead of schedule. Some cargo moving between China and Vietnam, and China and Thailand, has shifted from air to road transport, and China-Europe rail remains an option for shipments that can tolerate a longer transit time. On the tightest lanes, booking space one to two weeks ahead is now the recommended minimum. Korea to the US currently needs around a week of advance notice, while some equipment cargo moving through Incheon needs closer to two weeks.

Capacity availability can differ considerably from one market to another
Kathy Liu, Dimerco

When a major hub becomes fully loaded, as Taipei has recently, cargo does not simply disappear. It waits for a later flight, moves onto an alternative routing, or, for urgent or larger shipments, gets carried on a charter service instead. For cargo that is not time-sensitive, switching transport mode altogether becomes a realistic option. What this really means is that a full hub does not stop trade, it just makes trade slower, more expensive, or both, and it is usually the shipper who ends up absorbing that cost, whether through a higher rate, a delayed delivery, or a scramble to find an alternative gateway at short notice.

Locking in space without overcommitting
This is where Block Space Agreements, or BSAs, come back into the story. A BSA is a contract in which a forwarder pays an airline to reserve a fixed amount of cargo space on a flight, whether they fill it or not, and it carries risk in both directions. Commit to too much space on a lane that later softens, and a forwarder pays for capacity nobody uses. Commit to too little, and they are exposed if that same lane suddenly tightens.

Industry analysis published by CXTMS, a transport management software provider, in August 2026, has proposed a more structured way to handle this uncertainty, rather than treating every block-space commitment as fixed until departure.

The approach works around a few simple checkpoints ahead of departure. Six to eight weeks out, the plan is to retain core, strategic capacity, but question any forecast volume that is not backed by a firm order or confirmed production. Three to four weeks out, the booked allotment gets reduced if actual demand consistently falls below a set threshold, such as 75% utilisation, across two planning cycles in a row. And seven to fourteen days out, any remaining excess capacity is released, unless the shipment's value or urgency justifies paying for the buffer anyway.

The idea is not to predict the market perfectly. It is to build a repeatable process for adjusting commitments early, rather than discovering the mismatch only once the flight has already departed.

So does adding more aircraft actually help?
This is the question the whole story is really circling. If outbound and backhaul cargo are permanently out of step, does simply flying more aircraft on a route fix the problem, or does it just create more empty capacity chasing the same limited demand?

Shafiu's answer, from the airport's side, is a useful reality check.

"Airline capacity is only fully usable when airport infrastructure, manpower, handling resources and coordination can support it end to end," he said.

That single sentence reframes the whole question. Adding aircraft increases the raw amount of space in the sky. But space in the sky is not the same as usable capacity. If the ground side of the operation, warehousing, staffing, customs clearance, trucking, cannot process that extra volume, the additional capacity does not translate into anything a shipper can actually use.

Seen this way, more aircraft alone does not solve a structural imbalance. It can even make coordination harder, if the ground infrastructure has not scaled up alongside it. An extra freighter on a route does nothing for a shipper if the cargo it carries then sits in a warehouse for two extra days because there was nobody available to process it. In some cases, adding capacity in the sky without adding capacity on the ground simply moves the bottleneck from the tarmac to the terminal, from a shortage that is visible and easy to talk about to one that is quieter and easier to overlook.

What actually helps, on the evidence gathered here, is a combination of things working together, each addressing a different part of the same chain. Forwarders need sharper forecasting and booking discipline, distinguishing confirmed orders from hopeful projections rather than committing to space on the strength of last year's numbers alone. Contracts need flexible structures, of the kind CXTMS describes, so that capacity commitments can adjust as the real picture becomes clearer. And airports need ground infrastructure capable of turning extra aircraft capacity into cargo that genuinely moves, with the staffing and coordination to match whatever is landing on the runway.

The empty half of the aircraft, in other words, is rarely solved by adding a second aircraft. It is solved by making sure everything around that aircraft, bookings, contracts, warehouses and people, can keep pace with it too. This holiday season, as much as any before it, will be won or lost not by how many aircraft airlines can find, but by how well the industry manages everything that happens once those aircraft land.