Repeated failures in the propulsion train on the Freedom-class littoral combat ships Little Rock and Detroit have raised the specter of a class-wide design flaw that could trigger an expensive reworking of a crucial component on 17 of the Navy’s small surface combatants.
The issue being investigated is whether there is a fundamental issue with the design of the Freedom-class’ combining gear — a complex transmission that connects power from two large gas turbine engines and two main propulsion diesel engines to the ship’s propulsion shafts, which propel the ship through the water with water jets.