New Threat Upgrade

New Threat Upgrade (NTU) was a United States Navy program to improve and modernize the capability of existing cruisers and destroyers equipped with Terrier and Tartar anti-aircraft systems, keeping them in service longer. It was a key component of then-President Ronald Reagan's 600-ship Navy plan.

USS Mahan (DDG-42) was selected to install and test the Terrier New Threat Upgrade (NTU) Combat System with the improved Standard Missile Two Block II (Extended Range). Testing lasted from October 1981- March 1985.

New Threat Upgrade allowed the full use of newer Standard missiles (SM-2) and improved the interoperability of the radar and computer systems aboard the ships. The system allows the ships to which it was fitted to time share illumination radars for multiple missile interceptions in a manner similar to the Aegis Combat System. Some sources claimed that NTU ships were superior in some respects to Aegis ships of the same era, particularly in the area of user interface. They were inferior in that they could not deal with a saturation missile attack as well as Aegis vessels.

The New Threat Upgrade to the Leahy class included massive remodeling of the ship from food service space rehabilitation to a main propulsion system overhaul. Entire systems were removed and replaced, for example the AN/SPS-40 air-search radar was replaced with the AN/SPS-49 air-search radar.

In 1988–90, the Kidd-class destroyers received the New Threat Upgrade, including a new superstructure and heavier mainmast cooperative engagement with Aegis Ticonderoga-class cruisers, which could control the Kidds’ surface-to-air missiles while they remained electronically silent. The Spruance class, the predecessor to and close relative of the Kidd-class, did not received the NTU. However, in response to criticisms that the as-designed weaponry was insufficient, 24 members of the Spruances were upgraded with a 61-cell Vertical Launch System for Tomahawk missiles which granted them much enhanced anti-surface capabilities beyond their original anti-submarine warfare mission.

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