Newsletter article: 10 basic facts about ULDs

We get a lot of questions about Unit load Devices (ULDs). So we’ve drawn up a list of answers to commonly-asked questions to give you a better understanding of not only ULDs but also the decision-making process of buying a ULD.

1. What exactly is a ULD?

ULD – Unit Load Device - is a generic term used in the aircraft/transport industry for air transport products. Whatever the cargo, if it’s going through the air, it has to be transported by a ULD.

ULDs are crucial in transporting air cargo safely, quickly and cost-effectively. They enable individual pieces of cargo to be assembled into a single unit, which can then be loaded on and off an aircraft with speed. And because they interface with an aircraft’s loading and restraint systems, effectively becoming part of the aircraft, they can’t move around during flight and damage the plane.

2. What type of cargo does a ULD carry?

ULDs convey all types of cargo, from passenger suitcases and express parcels to Formula 1 cars, complete emergency response units and solar array wings. Shipping perishable goods? You may need a temperature-controlled container. Transporting a horse and groom? You’ll want one of our safe, humane horse stalls.

3. ULDs can be pallets or containers. But what’s the difference?

Both air cargo containers and air cargo pallets/nets allow a large quantity of cargo to be bundled into one unit and loaded onto aircraft. Here’s the difference. Containers protect cargo from all kinds of weather and guard against damage because they have a rigid casing. They also prevent unauthorised access. Pallets are cheaper than containers. They use nets to restrain the cargo, including cargo difficult to fit into containers (e.g. oversized cargo). Pallets are also stackable, making them efficient and easy to store empty and return by plane. So whether your ULD is a pallet or a container depends on your cargo and other aspects such as protection, security and price.

More general info on ULD (benefits, regulations and differences)

4. What options do I need to consider when buying a container?

There are many different types of containers available to you. Some are collapsible, some are insulated; others are fire-resistant or refrigerated. The variation is almost endless. Take, for example, the type of material used. Some customers demand light-weight material to reduce the overall weight of the ULD.

Do you want a fabric or solid door? A forward or side door? Should it swing open to the full width of the ULD for easier loading or does it need to be hinged or folding? Perhaps you have to remove it altogether?

There are other things to consider when ordering a container. Does it need to be forkliftable? Do you want to add your corporate logo to it? Do you have specific security requirements, like a door lock and ISO corner fittings? We’ll take you through all the options available, so you end up with your perfect and unique ULD.

To give an idea of the possibilities, we have categorised the various types of ULDs available and their features in six product families: efficient, cool, specialised, comfortable, fireproof and small.

5. How do you identify and track an individual ULD around the world?

Because many different parties handle ULDs as they pass between airlines and airports around the world, a system was needed to identify each ULD and its type easily and quickly. So the International Air Transport Association (IATA) introduced a global standard system of identification. Accordingly, each ULD is assigned a unique ULD code, which is clearly visible on the relevant unit. Now all manufacturers, cargo handlers and airlines can identify the ULD type and the owner at a glance.

6. Each ULD has a unique code. What do the letters and numbers mean?

This code, introduced by IATA to identify each ULD, is a unique combination of letters and numbers. It starts with a three-letter prefix that classifies the ULD (i.e. its type, base size and contour). This prefix is followed by a unique 4 or 5-digit serial number to distinguish it from others of the same type. The last two or three characters designate the owner of the ULD (e.g. the airline).

More info on ULD coding system

7. What’s a certified ULD and do I need one?

Every ULD we produce complies with the regulations of the Civil Aviation Authority (CAA). These certified ULDs are robust enough to cope with all likely and extreme circumstances during flight. They guarantee the cargo won’t move around the hold, endangering the aircraft’s structure and systems. Certified ULDs are accepted by all airlines.

Non-certified ULDs are also available. Manufactured to the same standards as certified ULDs, they need indirect approval from the carrier (airline) and can only be loaded into an aircraft in line with the aircraft manufacturer’s instructions. However, because ULDs are often transferred between aircraft and even other airlines before reaching their destination, and some carriers do not accept non-certified ULDs, it’s usually safer and more convenient to use certified ULDs.

More info on certified and non-certified ULDs

8. Can my ULD be loaded onto any aircraft?

Most ULDs are compatible with one or more aircraft types, but not all. So how do you know which aircraft corresponds with the ULD you have or want? We’ve developed a compatibility tool to help you determine just that.

9. Why do containers have different contours?

A container is shaped to fit in the plane’s body. Since the holds of aircraft come in many shapes and sizes, ULDs also have to come in many shapes and sizes. By adapting the contour to the shape of the plane’s hold, we can maximise the volume of cargo you transport. A major consideration in selecting the contour is the location of the container in the plane: will it be on the upper or lower deck? Here is a list of contours.

10. My ULD maximises the cargo space of an Airbus A380? What about other aircraft?

A ULD can be an optimal fit for one or more than one type of aircraft. Of course, if the ULD isn’t an optimal fit, that doesn’t mean it can’t be used in another type of aircraft. In fact, it may be compatible with several different aircraft. It simply won’t be making the most of every hold’s space. You can check which planes your ULD fits exactly by using our compatibility tool.

More info on optimal and non-optimal fit

If you’d like more information on ULDs in general, just visit our website. And if you’d like information on a specific ULD or wish to submit a Request for Quote, please call us on +31 (0)10 479 8100. We’d be delighted to hear from you.

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