CLASSIC TROLL AN/ULR-21
New Attack Submarine (NSSN)
Electronic Support Measures (ESM) System
Formerly called ASTECS - Advanced Submarine Tactical ESM Combat System - this project will develop a
new ESM system for the NSSN that will support operations in both the open-ocean environment and the
complex littoral signals environment. Developed by Lockheed Martin, Syracuse, NY, it consists of signal
receivers, displays, and advanced processing and analysis equipment. ESM provides detection, identifica-tion,
and direction-finding for radar and communication signals emanating from ships, aircraft, submarines, and other
emitters. ESM equipment is used by attack submarines to aid in self-protection, situation awareness, and
intelligence-gathering for battle group support. Battle group dissemination of the information gathered from
these signals will be provided via the ship’s combat control system and communications equip-ment. The NSSN
ESM system provides a minimally manned ESM capability providing several critical functions for radar and
communications signals: detection, signal acquisition, identification, localization, and threat warning to the combat
system. NSSN ESM system signal reception requires an antenna that can be located on the photonics or ESM
mast. NSSN ESM and the Integrated Electronics Mast (IEM) programs are companion programs that, when
combined, will form an integrated submarine ESM suite. The NSSN ESM system is being considered for
eventual backfit into Seawolf (SSN-21) and Los Angeles (SSN-688/6881)-class submarines. The program
entered Engineering and Manufacturing Development (EMD) in October 1994, but was rescoped as a result of
FY 1998 Program Objective Memorandum (POM 98) funding reductions.
Sources and Methods
http://www.fas.org/irp/program/collect/nssn-esm.htm
Created by John Pike
Maintained by Steven Aftergood
Updated Wednesday, December 30, 1998 8:54:09 AM