The SAP platform replaces an environment consisting of about 25 different systems that were not integrated - a situation which resulted in islands of data stored on software that had little or no supplier support.
Twenty-eight Rolls-Royce and Bentley staff worked closely with 12 full-time consultants from Gedas during the project.
Uwe Koch, Rolls-Royce IT executive, said that a major impetus for the SAP project was the need to take advantage of the integration of data possible with modern software and so move to a common environment.
According to Koch the main challenge was cleaning data during the migration. "We didn't achieve all our targets and still haven't finished cleaning the data. We are in a stabilisation period. Making enough people available for these tasks has been difficult," he said.
Simon Bragg, an analyst with ARC Consulting, said that since existing enterprise resource planning systems were often built using different data sets, establishing a common data description, or material master data, was the greatest obstacle to success in such a project.
"To run a whole company on one instance of SAP, you need the same material master data for each site, and each site's material master can contain 10,000 items, and be 400 fields wide.
"Many global companies are creating a new, single material master by hand, but this takes teams of three to five people many months per site. It is not an exciting task - it's more boring than playing Snap with decks of 10,000 cards."
Koch said there were also difficulties in measuring the benefits of the new system. "You can never really understand the intangible benefits of such a project. We are achieving a unified environment, which is obviously better, but whether you can identify savings is difficult to say."
Seeing the project as important for the business rather than being just an IT task was key, Koch added, and this helped to ensure that the consultant's progress was measured against business drivers. "Each business sector provided between two and five staff per module to monitor progress and to help communication both ways," he said.
The implementation of finance, logistics, human resource and payroll modules links with the engineering side of the operation and its project modelling software which generates bills of materials for vehicle production.