Unit Load Devices and Civil Aviation – A Brief History


What is a ULD?

According to IATA -(the International Air Transport Association), “A ULD is a device for grouping and restraining cargo, mail, and baggage for air transport. This could be either a fixed container or a pallet with mesh or netting to restrain the contents.”

Boeing B-777F MainDeck Loading timelapse – YouTube

When did airlines first use ULDs?

International airfreight in the late 1960s saw the need for a uniform method and an interchangeable packing device across all aircraft and airlines. So, the Unit Load Device (ULD) was born. This device has made leaps and bounds from the humble packaging crate of the 1960s to the high-tech Bluetooth-enabled device of the present day.

In the 1950s / 60s, there were not any purpose-built air freighters and airlines made do with what they could. Aircraft used ULD but lacked uniformity and were made to suit individual aircraft.

 It wasn’t until the DC-8 and Boeing 707, a new generation of jet aircraft, able to cruise at speeds of around 550 mph with a payload in the freighter version of up to 40 metric tonnes, came about that airfreight began to be taken seriously.

The invention of the ULD allowed for easy handling and maximised capacity. They were constructed from aluminium, light, and easily damaged metal, so the way cargo handlers handled them had to stop them from sustaining considerable damage. A ULD is designed to suit the contours of the belly of an aircraft.

Over the years, other types of special containers have been developed, such as temperature-controlled boxes for perishable cargo, pharmaceuticals, and live animal stalls.

From the early 1970s, standardisation of UDL  started between airlines and manufacturers, but IATA did not formalise the use of ULDs until 2013.

Freight and passenger planes

The first jumbo jet was the Boeing 747-100, which made its maiden flight from Seattle on 9 February 1969. The B747 was built as a military freighter for the US Air Force. Still, as Lockheed won the  C5 – Galaxy contract, Boeing concentrated on developing the B747 as a commercial passenger and cargo aircraft, which flew the world for 45 years, taking on many versions.

Hong Kong, Singapore, Miami, New York, and Dubai were some of the first international airports to transport goods by air in significant quantities.

Significant Dates

  • January 1970 – the first Boeing 747 travelling between New York and London was the first ever commercial flight of an aircraft to carry passengers and ULD. Up until that time, ULD operations had only been on freighter aircraft.
  • Some airlines set up ULD CARE (or the IULDUG) to enable the transference of ULD between aircraft. The system worked well because there were financial obligations in the form of a “late penalty” when a ULD was not returned on time.
  • The system was not without its challenges, with large amounts of paperwork and some airlines clocking up enormous fines for late returns.
  • The 1980s – The advances of wide-body aircraft saw multiple airlines carrying large cargo volumes. At this time, some airlines chose to outsource their cargo handling to third-party brokers and providers.
  • 1988 – The A320 – Air France was the first single-aisle passenger aircraft designed to accommodate ULD. Rapid growth in the express courier industry happened around this time also.
  • The 1990s – Cargo handling facilities were becoming more sophisticated, as well as further outsourcing of cargo handling. With more air cargo being shipped, the expense of repairing damaged ULDs was mounting. In addition, increasing fuel costs meant lighter and more flimsy cargo containers.
  • August 1997 – Fine Air flight 101 crashed upon take-off, and investigators determined that movement in the cargo hold contributed to the accident. It was found that many aircraft were not considering weight and balance procedures.
  • China began full-scale exports of electronic and computer goods, and the temperature controlled ULD was moving into the air cargo space.
  • The 2000s – Global Trade and air cargo were expanding rapidly with new routes, larger aircraft and more complex fleets.
  • 2005 Advisory Circular AC120-85 Air Cargo Operations by the FAA was released in response to the Fine Air crash seven years earlier. As a result, cargo inspectors were put through comprehensive training and began to make spot checks on airlines to ensure weight and balance procedures were being adhered to.
  • During this time, air cargo was being shipped worldwide in growing volumes, fuel prices once again skyrocketed and with it, the race to find the lightest material to build ULDs from.
  • 2010 – World Cargo Symposium announced an initiative to reposition the ULD as a core cargo activity. IATA and IULDUG decided to go their separate ways, and IULDUG was rebranded, ULD CARE and became an independent operation.
  • Air freight operators recognised that the current paper trail used to track ULDs was unworkable, and a web-based system was designed by an independent third-party supplier.
  • It was in 2010 that UPS 6 Freight carrier crashed due to an in-flight fire while flying from Dubai to Germany. This crash resulted in the death of both crew members on board. In addition, it highlighted the dangers of flying with lithium batteries as cargo and prompted a revaluation of safety procedures for pilots who were overcome with smoke in the cockpit.
  • 2011 – just one year later, Asiana Airlines Flight 991, a Boeing 747-400F cargo aircraft on a flight from South Korea, to China, crashed into the sea after suffering a main-deck fire caused once again by lithium batteries on board. Both pilots, who were the only two people on board, were killed.
  • 2013– another air crash, this time a National Cargo Freighter carrying heavy-duty military vehicles crashed during take-off as cargo broke loose.   Seven crewmen were killed, and investigators found that the vehicles were inadequately restrained.
  • These crashes promoted the development of fire containment covers and fire-resistant containers to provide vital protection from potential fires and improved cargo restraining devices. But not all airlines could afford the costly changes, which led to IATA and ULD CARE formulating regulations.
  • 2013 IATA released the 1st Edition of the IATA ULD Regulations (ULDR) and subsequent promotion of the IATA ULD Safety Campaign since 2016.
  • 2018 – ULD CARE realised the potential to use Blockchain as an operating platform for an upgraded version of the current IULDUG. It was believed that a Blockchain-based platform could both replicate and enhance the current IULDUG system.
  • The not-for-profit organisation ULD CARE launched the ULD Code of Conduct. “Based on and complimenting the IATA ULD Regulations, which can be considered to be the ‘bible’ for all ULD operations, it is the intention that the code becomes the basis for ULD operational standards in organisations regardless of size and scale,” said Bob Rogers in 2018
  • In 2022, The worldwide Market for Air Freight Unit Load Devices (ULD) is valued at 357.6 million USD and is expected to reach 495 million USD by the end of 2026 despite some initial setbacks due to Covid19 pandemic.

As you can see the ULD has certainly evolved and changed over the past 60 years with new technology and the necessity for safe delivery of cargo worldwide.

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