Cargo control departure

With half a million tons of air freight and rising to deal with in any given year, British Airways’ materials-handling challenges at London’s Heathrow Airport are enough to make most other people’s pale into insignificance. But a massive project being undertaken by the airline should go a long way towards ironing out these problems. At […]

With half a million tons of air freight and rising to deal with in any given year, British Airways’ materials-handling challenges at London’s Heathrow Airport are enough to make most other people’s pale into insignificance. But a massive project being undertaken by the airline should go a long way towards ironing out these problems.

At Heathrow, BA is midway through building a new World Cargo Centre which is set to open in January 1999, incorporating state-of-the-art materials-handling hardware; sophisticated planning software; and electronic data interchange links to allow customers to book consignments directly into the central system.

The £250m cost of the building is the airline’s biggest-ever investment outside aircraft.

The centre was needed, says Bob Howell, World Cargo Centre operations manager, because the existing handling facility, inherited from BA’s precursors British European Airways and the British Overseas Airways Corporation, was reaching the limit of its 0.5 million tonnes annual capacity. ‘We looked at improving the existing facility but it couldn’t have been brought up to the required standard,’ says Howell.

The new facility will provide an annual capacity of 800,000 tonnes from the first day of operation, with the capacity to increase to a million tonnes when needed. Air freight is growing at 6 7% a year.

The centre comprises a 300m long cargo-handling building with 82,000m2 floor area on four levels, and an adjacent 6,300m2 business centre.

The heart of the cargo-handling system is its computerised planning system, with links to the outside world allowing extensive electronic trading with customers. BA’s business is being re-engineered to allow its outstations round the world to link directly into the system too.

Already, 80% of BA’s customers can trade electronically with the airline and the company hopes to increase this figure, on the basis that cargo from such customers will receive priority treatment. Customers will be able to track the progress of their cargo electronically.

Customers with goods to send will provide details of the consignment and request a delivery time electronically, two to six weeks in advance. The planning system will allocate a 30 minute slot for the consignment to arrive at the centre. The truck’s arrival at the gatepost with a manifest will signal to the planning system to earmark storage capacity within the centre.

The cargo centre is divided up by level according to function.

The ground floor is given over to collection and delivery. Level two will be the ‘break-and-build’ floor where cargo is transferred from storage cages used on the land side to the standard pallets or unit load devices (ULDs) used on the aircraft. Level three will be used for sorting small packages and consignments prior to break-and-build or customer collection, and is highly automated. The fourth level is the automated consignment store with lifts for moving goods to and from the floors below.

As well as being divided vertically, the building is split in two along its length, with storage for cages at the land side of the building, and storage for ULDs to the air side.

When a truck arrives, following a validation check at the gatepost the driver and registration number will be photographed. Variable message signs will direct the truck to one of 30 unloading docks.

Cargo will then be divided into four streams according to size and shape.

‘Out of gauge’ packages are split into two categories. Those that are too big to fit into the standard cages used within the cargo centre, or which weigh over a tonne but can still fit on a ULD, will be handled using forklift trucks and manual storage and retrieval. A package that is out of gauge even for the ULD system, such as a ship’s mast, will be taken direct to the aircraft side by a road truck for loading.

Parcels weighing less than 15kg will travel via a small-parcel conveyor, consisting of a series of buckets, one for each parcel. Parcels will be consolidated into larger consignments in standard cages automatically. Bar coding the IRTA 606 standard has been agreed after discussions with customer groups will be used to track each parcel, and also to instruct the conveyor where to store it. The bucket of the conveyor tilts at one of 38 cage-filling stations within the storage area, to unload the parcel into a standard cage.

The cage-filling system, developed by GEC-Alsthom and Lodige, is designed to tilt the cages for filling so that parcels slide gently down the side of the empty cage rather than dropping straight to the bottom; the cage is progressively returned to the vertical as it is filled.

‘Normal’ parcels weighing up to 100kg will also be placed in cages, one cage per consignment, and stored in the cage store.

Here, the cage storage system takes over the tracking function from the bar coding. Cages will be moved vertically by hoists, and horizontally on cage transfer vehicles and standard roller conveyors.

At a time worked back from the aircraft’s departure via a direct link to the airport scheduling system, cages will be moved to the break-and-build area for consolidation into ULDs.

There will be 11 break-and-build ‘fingers’, each containing six workstations, with space to add a further four stations on each aisle. At each station, cargo will be scanned from the cages into a ULD. Goods will be transferred from cages into ULDs by a specially designed manipulator. This is effectively a fork-lift supported from the ceiling and capable of lifting 1,000kg, providing the lifting capacity of a forklift without needing the space for a forklift to work in.

Once loaded, ULDs wait in the air side storage area, tracked automatically by the system. They are transferred within the store by vertical hoists and special transfer vehicles for horizontal movements. When the time arrives to load the ULDs, they will be transferred to standard dollies to take them out to the aircraft.

For incoming cargo, the process is reversed, except that an incoming ULD will be identified by a radio tag which will announce its arrival to the cargo centre system.

Consultant WS Atkins is responsible for the design of the building and services, and also for the conceptual design of the handling system. Atkins brought in specialist Lodige to assist with simulation and validation of the proposed system.

Lodige then teamed up with GEC-Alsthom to bid for the detailed design and supply of the materials- handling system. The joint venture won the £90m contract.

Timing for the installation of the handling system is extremely tight. ‘They have to deliver to a timescale compatible with the overall programme,’ says Howell. ‘As soon as a floor is complete, they have to put the kit in.’

A rigorous series of performance targets, still to be agreed, will be carried out during the first year of operation to verify that the system can meet the 800,000 tonnes/year target. If all goes well, cargo handling headaches should become largely a thing of the past for BA and its customers.