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When a generator part fails at a remote site in the PNG Highlands, nobody asks whether air freight is expensive. When a family is moving house to Suva, nobody seriously considers flying their furniture. Most Pacific shipments sit somewhere between those two extremes, and that's where the choice between air and sea gets interesting.
This guide compares the two modes on the things that actually matter for shipments from Australia to the islands: speed, cost, size and weight limits, security screening, dangerous goods and reliability. For the full picture of Pacific logistics, start with our complete guide to shipping to the Pacific Islands.
Key takeaways
- Air freight is quick but priced on chargeable weight, which penalises bulky cargo heavily.
- Most air cargo to the Pacific flies in the hold of passenger aircraft, so piece size, weight and capacity are limited.
- All international air cargo leaving Australia must be security examined or come from a Known Consignor.
- Many common goods, including some lithium batteries and aerosols, are restricted by air but can go by sea when declared properly.
- Compare the cost of freight with the cost of waiting. Downtime often decides the answer.
Air vs sea at a glance
| Factor | Air freight | Sea freight |
|---|---|---|
| Speed | Days, including clearance | Weeks, depending on sailings and routing |
| Cost per kilogram | High | Low |
| How it's charged | Chargeable weight: actual or volumetric, whichever is greater | Per container (FCL) or per revenue tonne (LCL) |
| Size and weight | Limited by aircraft hold and door size | Containers, flat racks and breakbulk for almost anything |
| Frequency | Several flights a week on main routes | Weekly to monthly sailings, depending on destination |
| Dangerous goods | Tightly restricted | More flexible when properly declared |
| Biosecurity | Same rules apply | Same rules apply |
How air freight to the Pacific works
Belly capacity, not freighters
Dedicated cargo aircraft rarely serve the Pacific Islands. Most air freight travels in the lower deck of passenger flights operated by carriers such as Air Niugini and Fiji Airways. That has three consequences. Capacity is limited and competes with passenger baggage. Piece size is limited by the hold door and the aircraft type, and routes flown by narrow-body jets can take much smaller pieces than wide-body services. And when flights are cancelled or reduced, cargo capacity disappears with them.
Chargeable weight
Airlines charge on whichever is greater: the actual weight or the volumetric weight. Volumetric weight is usually calculated at 6,000 cubic centimetres per kilogram, which works out to about 167 kilograms per cubic metre.
Example. A carton measuring 80 by 60 by 50 centimetres that weighs 20 kilograms has a volume of 0.24 cubic metres, or a volumetric weight of 40 kilograms. You pay for 40 kilograms, double the actual weight. By sea, the same carton would be charged as 0.24 of a revenue tonne, usually rounded up to the LCL minimum.
Security screening in Australia
Since March 2019, all outbound international air cargo from Australia must either be examined at piece level by a Regulated Air Cargo Agent or originate from an approved Known Consignor before an airline will accept it, as the Department of Agriculture explains. In practice, your forwarder arranges the examination, which can mean breaking down a wrapped pallet to check individual cartons. Build that time into your plans, and pack so that pieces can be examined and re-secured easily.
Dangerous goods
Air is far stricter than sea on dangerous goods. Lithium batteries, aerosols, paints, adhesives, fuel-powered equipment, perfume and many cleaning products are regulated, and some can't fly at all on passenger aircraft. Items that are routine by sea, provided they're declared and packed correctly, can be refused outright at the air cargo terminal. If in doubt, ask your forwarder before you book.
How sea freight compares
Sea freight is charged per container or per revenue tonne, where one cubic metre equals 1,000 kilograms for charging purposes. That is roughly six times more generous to bulky cargo than air's 167 kilograms per cubic metre, which is why furniture, building materials and vehicles go by sea almost without exception.
The trade-off is time. Port-to-port sailing times from Brisbane are short, but sailings to many destinations are weekly at best and monthly at worst, and clearance at destination adds days. Our guide to FCL vs LCL to the Pacific Islands explains how to choose between the two sea freight options.
The cost of waiting
The freight bill is only half the comparison. The other half is what it costs you to wait.
- Downtime. If a mine, power station or fishing vessel is idle until a part arrives, a day of downtime can cost more than the entire air freight bill.
- Lost sales. A retailer with empty shelves before Christmas loses trade it won't recover.
- Perishability. Fresh food, flowers, vaccines and some chemicals simply can't survive a slow journey.
- Working capital. Stock on the water is money tied up. For high-value, low-volume goods, faster transit can pay for itself.
On the other side, sea freight lets you ship more at once and hold a buffer of stock in-country, which can make urgent air shipments less necessary in the first place.
When air freight wins
- Urgent spare parts and breakdown repairs
- Medical supplies, vaccines and laboratory samples
- Perishables and live goods, where permitted
- High-value, low-weight goods such as electronics and documents
- Small consignments to destinations with infrequent sailings, where the next ship is weeks away
When sea freight wins
- Anything heavy or bulky, including furniture, building materials, machinery and vehicles
- Household moves and personal effects
- Regular stock replenishment that can be planned ahead
- Goods restricted as dangerous goods by air
- Project cargo and oversized items. See our guide to project cargo in the Pacific.
Mixing the two
The best Pacific supply chains rarely rely on one mode. Common approaches include:
- Splitting a shipment. Fly the items needed immediately and send the rest by sea.
- Holding stock in-country. Ship critical spares by sea in bulk so that air freight becomes the exception.
- Using express couriers for documents and small parcels, where door-to-door handling and tracking justify the price.
- Timing around cyclone season. Build up stock by sea before the peak months, when both flights and sailings can be disrupted. See shipping during Pacific cyclone season.
Pacific considerations for both modes
- Biosecurity applies equally. Air cargo and mail are inspected just as closely as sea freight. Clean goods and permits are just as necessary. See prohibited and restricted items.
- Clearance still takes time. Fast flights don't help if the paperwork isn't ready. Send documents to your broker before the goods depart.
- The last leg matters. Cargo for outer islands may still finish its journey by inter-island boat or domestic flight.
- Duty and tax apply either way. Customs value usually includes freight, so a higher air freight bill can mean more duty and VAT or GST too.
Frequently asked questions
How long does air freight to PNG or Fiji take?
Airport-to-airport, often a few days from an east coast capital, depending on flight frequency and capacity. Allow extra time for security examination in Australia and for customs and biosecurity clearance on arrival.
What is chargeable weight?
It's the greater of the actual weight and the volumetric weight, usually calculated at 6,000 cubic centimetres per kilogram. Light, bulky cargo is charged on its volume.
Can I send lithium batteries by air to the Pacific?
Some can travel under strict dangerous goods rules, others can't fly on passenger aircraft at all. Tell your forwarder exactly what you're shipping, including batteries inside equipment, before you book.
Is air freight ever cheaper than sea?
Rarely on freight cost alone. For very small, light consignments it can come close once LCL minimums and fixed fees are added, and it often wins once the cost of waiting is counted.
How this guide was researched
This guide draws on Australian Government guidance on air cargo examination and the Known Consignor scheme, standard airline chargeable weight conventions, and the author's experience arranging urgent and planned freight to Papua New Guinea, Fiji and the Solomon Islands. Rules and capacity change, so confirm details with your forwarder before you book.
Written by
Peyton Brown
Senior Editor of The Pennsy's Pacific shipping desk, with more than a decade in Pacific freight operations, documentation and customs coordination across Papua New Guinea, Fiji and the Solomon Islands.
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