In 1996, Rockwell sold its military and aerospace division, including responsibility for the "Collins" combat system, to Boeing. Boeing attempted to produce a workable combat system, but believed that this could only be done if the changes in technology were accounted for in a contract alteration, which the RAN and the Australian Government initially refused to do. Boeing then requested assistance from Raytheon, and after further negotiations with the Government resulted in a reduction of the system capabilities, the companies were able to stabilise the system and deliver Release 2.0 at the end of 1999. Boeing sold its naval systems division to Raytheon in May 2000, making the latter company solely responsible for completion of the combat system. After this, the submarine project began investigating ideas for a new combat system. Because there was not enough time to evaluate the replacement system to include it in the "fast track" program, "Dechaineux" and "Sheean" were fitted with the old Rockwell combat system, which was enhanced by the addition of sub-systems developed during the early 1980s for the "Oberon"-class mid-life upgrade and commercial off-the-shelf components. Even with the enhanced system, it was believed that the capabilities of the fast track "Collins" boats was at best equivalent to the "Oberon"s.