We developed a decision support system (DSS) for the aircraft maintena
nce department of KLM Royal Dutch Airlines at Schiphol Airport. This d
epartment inspects and maintains aircraft during their ground time at
the airport. Its main resource is its workforce. Since January 1990 th
e DSS has supported management in analyzing several capacity planning
problems related to the size and the organization of the workforce. In
particular, management uses the DSS to determine the appropriate numb
er of maintenance engineers and their training requirements, and to an
alyze the efficiency and effectiveness of the maintenance department.