CelsiusTech Systems AB (3rd Case)

Company Background

CelsiusTech Systems AB originally was a department of Philips, later became an independent company, and finally became an affiliated company of the Saab Group, Sweden, operating under SaabTech AB. SaabTech AB is a leading supplier of avionics and electronic warfare systems.


In the mid 1980s, CelsiusTech simultaneously obtained two contracts to build naval control systems. The systems had to be hard real time, fault tolerant, and highly distributed. They had to interface with radars and other sensors, missile and torpedo launchers.


Due to its prior experiences CelsiusTech could estimate the complexity and came to the conclusion that it could not realise these contracts by two separate teams. CelsiusTech recognised that the two systems had more similarities than differences, even though they had to serve ships of different classes in different navies. With its extensive background in the domain, CelsiusTech started one of the first software product lines, which is still running today, under the name ShipSystem 2000.


The ability to react quickly to customer needs in a hard-fought market, with strong competitors and only a few customers, gives a strong competitive advantage. CelsiusTech could quickly enter the new market of avionic systems because it reused 40% of its code directly from Ship System 2000. The general reuse rate is about 80% in the normal naval scope of the product line. CelsiusTech has also inverted its software/hardware costs ratio from 65:35 to 20:80.


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  • L. Brownsword and P. Clements; "A Case Study in Successful Product Line Development", Technical Report no. CMU/SEI-96-TR-016, Carnegie-Mellon Software Engineering Institute, 1996.
  • SPLC2 - Product Line Hall of Fame (Website)