Navy hunts hostile targets on 45 warships using AN/SRS-1A(V)

By Miriam Adler · August 14, 2026

Hostile targets were tracked by a digital eye that does not blink, using civilian office hardware to turn the ocean into a grid of monitored frequencies for years.

“Front-end Stare.” That is the phrasing used by the Navy to describe the parallel architecture of the Automated Digital Acquisition Subsystem (ADAS). It is a clinical term for a digital eye that does not blink, designed to detect, locate, and categorize “hostile target signal acquisition” from a distance. This is not a memo or a diary of a sailor; it is a program description hosted on a mirror of the Federation of American Scientists (FAS) Intelligence Resource Program, and it reads as a brochure for the mechanization of suspicion.

"Front-end Stare"

The system in question is the AN/SRS-1A(V) Combat Direction Finding (CDF) system. According to the FAS record, its primary purpose is to provide warship commanders with “near-real-time indications and warning” and “situational awareness.” In the lexicon of the Navy, this translates to the ability to listen to the electromagnetic spectrum and decide who is a threat before they are even visible on a horizon.

The CDF evolved in blocks. Block 0, the AN/SRS-1, established the basic shipboard direction finding architecture. It featured a “more robust HF DF deck-edge antenna array” and a “mast-mounted VHF-UHF antenna.” It was designed for the specific purpose of supporting Over-The-Horizon-Targeting (OTH-T). To put it plainly: the system finds the signal so that a weapon can find the target.

By the time the Navy moved to Block 1—the AN/SRS-1A(V)—the capabilities shifted toward the “exotic.” The FAS page notes the inclusion of a “Programmable exotic signal recognizer.” The record does not define what constitutes an "exotic" signal, only that the system is capable of recognizing it. This programmable nature allows the military to update its definitions of hostility in real-time, integrating new signal recognition algorithms to ensure that whatever the enemy transmits, the ship can categorize it and archive it into the tactical data system.

Document imagery from irp.fas.org From the files: irp.fas.org

Commercial Off-The-Shelf

There is a telling detail in the FAS description regarding the cost and reliability of the system. The Navy claims that Combat DF “greatly improves on existing Outboard system technology” by utilizing “Commercial Off-The-Shelf workstations.”

This is the point where the civilian market becomes an unwitting accomplice to the machinery of war. By using commercial hardware, the Navy reduced costs and increased reliability, effectively turning standard office computing power into a tool for “wideband signals exploitation.” The efficiency of the private sector—the same drive for cheaper, faster, more ubiquitous hardware that powers the modern economy—was harnessed to make the process of target acquisition more seamless.

These systems were not merely theoretical. The record states that the AN/SRS-1A(V) successfully completed developmental and operational testing in the summer of 1994. By the third quarter of fiscal year 1993, full-rate production for Block 0 had already begun. The deployment was wide, targeting both the Wasp (LHD-1) class of amphibious assault ships and the Arleigh Burke-class destroyers.

DDG-72

The public record establishes the Arleigh Burke-class as the most numerous class of warships in the U.S. Navy, centered on the Aegis Combat System. The FAS document specifies that Block 0 was installed during the construction of Arleigh Burke Flight II ships, specifically naming DDG-72 and follow-on vessels.

For those on DDG-72 and its sister ships, the AN/SRS-1A(V) was more than a piece of hardware; it was the primary means of “narrowband signals exploitation.” The system provided a “TACINTEL Terminal” and displays for signal parameters, allowing an operator to dynamically tune receivers to “frequencies of interest.” It turned the ocean into a grid of frequencies to be monitored and managed.

The scale of the rollout was ambitious. The FAS mirror indicates that the Block 1 system was intended to outfit seven LHDs, 35 DDG-51 Flight IIs, and three shore sites. The transition from the basic architecture of Block 0 to the digital acquisition of Block 1 represented a shift toward an automated, parallel process of surveillance—one where the human operator manages the system, but the “Front-end Stare” does the hunting.

While the FAS page serves as a technical summary, it leaves a void where the human element should be. We see the “Operator Interface CSCI,” but not the operator. We see the “hostile target,” but not the people on the other end of those signals. We are left with the logistics of detection: the MS III decisions, the FY 1997 backfits, and the contractual milestones of full-rate production.

The cycle of obsolescence in military surveillance is rapid. The record concludes by noting that beginning in fiscal year 2000, the Combat DF system would be superseded by the Cooperative Outboard Logistics Update (COBLU) Phase 1 system during the construction of DDG-51 class destroyers, promising an “even greater level of capability for processing modern signal modulations.”