the submarines' service lives. The hardware for the original combat system was based around the Motorola 68000 family of processors. The replacement combat system consists of the tactical and fire control components from the Raytheon CCS Mk2 system, combined with the sonar interfaces developed for the improved combat system used aboard Sheean and Dechaineux. Countermeasures include a Condor CS-5600 ESM intercept and warning unit, and two SSE decoys. The boats are fitted with a Marconi SDG-1802 degaussing system, and a receive-only Link 11 combat information exchange datalink. In October 2006, Sagem Défense Sécurité was selected to fit the Collins class with SIGMA 40XP gyrolaser inertial navigation systems. Ship's company Originally, the standard complement of each submarine was six officers and thirty-six sailors, with facilities to carry an additional twelve personnel (usually trainees). This number was minimised by the RAN during design, which insisted that functions be automated where possible; the RAN also requiring that each sailor have his own rack and did not need to 'hot bunk'. It was originally intended that multiple ship's companies be established per submarine, and that these be rotated to maximise the submarines' time at sea without adversely affecting personnel, but difficulties in maintaining submariner numbers made this plan unworkable. Enlisted submariners are accommodated in six-bunk cabins. In May 1997, two groups of six female sailors were posted to Collins and Farncomb to test the feasibility of mixed-sex submarine companies. Following the trial's success, eleven female sailors and one female officer commenced submarine training in 1998. Officers and senior enlisted submariners slept in mixed accommodation, but junior enlisted submariners could be deployed in groups of only six: one of the enlisted cabins was set aside, and all six bunks in the cabin had to be filled. Mixed accommodation for all female submariners was approved in June 2011, in order to increase posting opportunities and help make up shortfalls in submarine complements. During the late 1990s, a combination of low recruitment and retention rates across the RAN resulted in the number of trained submariners falling below 40% of that required. As an attempt to retain submariners, the RAN offered a one-off A$35,000 bonus in 1999. Other measures introduced around the same time included priority transfer of volunteers for submarine training and rotating submariners between sea and shore assignments to relieve them from continual sea service and prevent burnout. A year later, these measures had increased submariner