The other kind of container
Air Cargo Container (ULD) Sizes
Sea containers never fly — aircraft holds are curved, pressurised and weight-critical, so aviation developed its own family: ULDs, shaped to hug the fuselage (that is why the LD3 has an angled base corner). If your cargo switches from ship to plane, it is repacked, and the size arithmetic changes completely.
Common ULD types
LD3 (AKE): 156 × 153 × 163 cm, 4.3 m³, max gross ~1,588 kg — the standard for A330/A350/B777/B787 lower decks.
LD6 (ALF): double-width, 316 cm wide, 8.9 m³.
LD7 (PAG/PMC pallet + net): 318 × 224 cm base — main-deck freighter workhorse.
PMC pallet: 318 × 244 cm, up to ~6,800 kg on freighters.
LD1 (AKC), LD2 (APE): B767-family equivalents of the LD3.
Air vs sea: the practical difference
A 20 ft sea container carries ~28 t and 33 m³; an LD3 carries ~1.4 t and 4.3 m³. Air freight prices by chargeable weight (actual vs volumetric at 1:6,000 cm³/kg), so dense cargo flies “cheap” per kilo and fluffy cargo pays for the space. The volumetric logic of the CBM calculator still applies — the divisor just changes.
Frequently asked questions
What are LD3 container dimensions?
156 cm wide × 153 cm deep × 163 cm high overall (with one angled base corner to fit the fuselage), 4.3 m³ internal volume, maximum gross weight about 1,588 kg. IATA type code AKE.
Can a sea shipping container go on a plane?
No — ISO sea containers do not fit aircraft holds and far exceed air weight economics. Cargo is repacked into ULDs (or onto aircraft pallets) for the air leg.
What is the difference between LD3 and LD7?
The LD3 is a closed lower-deck container of 4.3 m³; the LD7 is a main-deck pallet with a cargo net, built on a 318 × 224 cm base and holding roughly 10 m³. Different decks, different handling — the LD7 carries about twice the volume.