Alain Flourens, head of Airbus's single-aisle programme, says that the upgrade involved the installation of a specially designed additional centre tank (ACT) in the A318's aft cargo hold.
"The ACT increases fuel capacity by 3,300 litres [871USgal] and range by 400-500nm [740-925km]," says Florens. "It gives the Elite a typical range of more than 4,000nm," he adds.
ACTs are already offered on the A320 family, including the A319-based Airbus Corporate Jetliner. However because the A318 has narrower cargo doors than the other A320 family models, Airbus is redesigning the ACT into two parts so that it can be fitted into the smaller aircraft.
Airbus says it has already signed up customers for the extended-range version of the Elite.