The Quetzalcoatl class marked the start of the evolution process of the Dreadnoughts. Building from features of  the abortive Battle cruiser projects of 2168 and 2210 the Quetzalcoatl class ships were the largest to enter service since the end of the Romulan War. The class differed from later Dreadnoughts in two ways, firstly it had a dual role as a Carrier, and secondly the third nacelle was only a small unit installed in the lower secondary hull. The class taught many valuable lessons used in later Dreadnought designs.