Darn Big Loader

Unique loader helps build Boeing's Dreamliner aircraft.

"Darn Big Loader" was not the original name for the "aircraft carrier" cargo loader, which is one third the length and half the width of a football field. But its conspicuous nickname, augmented throughout the design and construction process, stuck for obvious reasons.

The longest loader in the world at 118 ft. 1 in., this loader was designed and built in less than 15 months by TLD at its facility in Sherbrooke, Quebec, Canada. It was unveiled and successfully tested in June of last year. The TLD DBL-110, built solely for Boeing's 787 program, is used for the loading and unloading of major 787 Dreamliner aircraft components into three specially built 747-400 Large Cargo Freighters (LCF)— with a greatly enlarged fuselage and a "swing tail" that opens to accommodate major Boeing 787 Dreamliner sections (the aircraft has naturally been dubbed the "Dreamlifter").

Five loaders were in operation toward the end of 2006 in Japan, Italy, Kansas, South Carolina and Washington. Additional loaders are soon to be operating in Everett, WA.

Why fly these massive components when normally, parts and assemblies are transported sea or land?

"We announced in June 2003 that the 787 would be the first commercial jet to have the majority of its primary structure — including the wing and the fuselage — made of composite materials," says Kurt Kraft, chief project engineer for the Dreamlifter. Using composite materials, according to Kraft, allows Boeing to build larger, more integrated assemblies that would originate from various parts of the world. "We decided to fly the major assemblies [because] our studies showed we could save between 20 to 40% over the cost of traditional shipping methods." Using the Dreamlifter, what once took weeks now takes hours.

The dream team

The project was a shared design effort between Boeing and TLD engineers beginning with the discovery phase in the spring of 2004 through to getting the contract in February, 2005. Boeing initially provided the operational concept, interface and control system requirements, as well as the overall direction. TLD implemented the design, providing and calculating the power requirements, structural geometry, stress analysis, hydraulic design and structural component configuration.

"Designing and building a cargo loader of this magnitude is a unique proposition," says Mike Bunney, director of global logistics for the Boeing 787 Dreamliner program. "A robust transportation system is essential to meeting the customer demand for the Dreamliner and a safe and efficient cargo loader is critical."

The DBL-110 is a critical part of the supply chain for the production of the Boeing 787 Dreamliner and, as such, it has been designed and equipped with a number of redundant systems as well as being subject to a number of reliability studies in component selection.

Two of the three Dreamlifter LCFs were modified at Evergreen Aviation Technologies Corp. in Taiwan. The third has been "inducted" into the factory and the modification process has begun. The first two began transporting 787 major assemblies in January.

The LCF fleet will ferry 787 wings and fuselage parts from partners in Wichita, KS; Charleston, SC; Grottaglie, Italy; and Nagoya, Japan to Boeing's Everett factory for final assembly. A cargo loader is based at each facility.

An operator seated in a cab atop the loader will drive the machine to the parked LCF. Sensors align it to the LCF's cargo-handling system to ensure safe loading and unloading.

Darn big challenges

Evergreen Eagle, a division of Evergreen Intl. Aviation (also responsible for operating the fleet of Dreamlifters), is Boeing's partner for all of the LCF's ground handling activities. Based in McMinnville, OR, Evergreen was chosen because it has extensive experience in managing cargo freight operations, including odd-sized cargo.

Though only four crew members are necessary for loading and unloading, special training is imperative. DBL training is provided by TLD and additional training for specific functions and equipment on the loader such as Caterpillar (engines), Allen-Bradley (PLC controller), Cybernetix (optical control) and Hydequip (steering) is provided individually.

Due to the exorbitant size and weights of the loads involved, other important details in training need to be addressed including emergency movement, alignment, steering and load control.

"One of the major challenges," says Bunney, "is the turn time necessary to meet the Dreamlifter flight schedule …which necessitated that [it] be unloaded and back loaded as quickly as possible." To reduce the turn time, it was decided the Dreamlifter would not be jacked prior to freight transfer, which meant the loader needed to be capable of following the movement of the LCF as the parts were transferred.

"In addition, we did not want any physical contact from the loader to the Dreamlifter," states Bunney. "This was solved by incorporating optical sensors." Carrying its maximum load, the DBL has the potential of damaging roadways, necessitating the use of 32 independently controlled tires on 16 steerable axles.

In the swing zone

Military and civilian cargo planes are loaded though the front or the rear. The Boeing 747-400 freighter is loaded through its lift-up nose section. However, the 787 composite structures are so large they could not be loaded in the same manner.

"So we decided to use a swing-tail system where the aft fuselage swings open for loading and unloading, says Kraft. "We knew that would work to accommodate the size of the asemblies and we needed to work with our design partners on a workable solution — we found it."

While the swing zone was difficult to complete during the modification process, according toKraft, the swing tail has performed flawlessly. It is guided by an enormous mobile tail support, which carries most of the weight of the 44,000-lb. tail and continually adjusts to changes in position during the opening and closing of the tail. This reduces wear and tear on the two hinges visible in the aft section of the fuselage.

Currently, there is no plan to use either the Dreamlifter or the DBL for any other application. "Our mission is focused specifically on 787 production and making the Dreamliner successful," says Bunney. "We expect to recoup the costs of buying the fleet of Dreamlifters and all the associated expenses for modifications, including the creation of specialized ground support equipment, within the first few years of the 787 production." To date, 38 airlines had logged 473 orders and commitments for the 787 worth more than $70 billion.

Bunney says it best, "When you have a team of people who are fully focused on the goal-and understand the importance of the work they are doing-personal considerations get set aside and you accomplish great things."

Karen Reinhardt is the editor of Gound Support Worldwide, a sister publication to OEM Off-Highway. This article was originally published in Ground Support's March 2007 issue.

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