From 1956 to 1960 Ernst Krolke worked for KLM Royal Dutch Airlines, Berlin, in Passenger and Cargo Handling. Prior to his first job with KLM, as a high school student in Berlin Ernst designed an on paper airline operations system. Airline operations and their improvement has been in abiding passion throughout Ernst’s life. From 1960 to 1965 Ernst worked for Qantas Frankfurt and Qantas London in Marketing Development. In 1966 he was invited to join Qantas in Sydney as part of the Schedule Planning and Development team. In 1977 Ernst was appointed as the Qantas Manager Fleet Planning & Scheduling.

In 1993 Ernst was promoted to Qantas Manager Network Development. In 1998 he was appointed Chief Executive Officer of Airport Coordination Australia (ACA), an independent company for the allocation of airport slots at congested airports in Australia and Abu Dhabi, Oman, Manila and Port Moresby. Ernst is recognised internationally as a founding father of airport/airline slot design and scheduling. This achievement has been recognised through his outstanding leadership and membership of a number of international aviation scheduling committees including: 1981 – 2015 member of the IATA Scheduling Procedures Committee, later Joint Slot Advisory Group (JSAG).