The Viscount-class Star Defender was a very large warship series developed by the Mon Calamari for use by the Allied Defense Fleet. The Viscount-class Star Defender was envisioned as the New Republic equivalent of an Executor-class Star Dreadnought.[6] The first prototype was a 3 km long battlecruiser,[5] measuring almost twice as much as the Mediator-class battle cruiser. The full production model was a 17 km long dreadnought.[5] Although slightly shorter in length than the Executor-class, the superior construction skills of the Mon Calamari enabled the vessel to carry more starfighters, as well as having a substantially smaller crew. Its shape was also more compact than the Executor-class[6] and it had heavier and more extensive armor. Envisioned as a counter to the many Super Star Destroyers still in Imperial hands, seen by Admiral Ackbar as the greatest threat to New Republic forces, the Viscount was the largest starship class ever constructed by the Alliance of Civilizations. Shorter and more massive than an Executor, superior Mon Calamari engineering enabled them to fit heavier armour and operate it with a substantially smaller crew than its progenitor. Although delayed by New Republic bureaucracy, the project was revived after the Dark Empire and Black Fleet Crisis demonstrated anew the need for vessels able to defend against such large threats. The class was designated a “Star Defender” in an attempt to avoid the negative connotations still associated with the Empire-favoured “Star Destroyer”. The Viscount-class Star Defender are used by the Allied Joint Navy