Naval Tactical Data System | 1961

Naval Tactical Data System 

The Naval Tactical Data System (NTDS) is a computerized information processing system developed by the United States Navy in the 1950s, which began being used on warships in the early 1960s. This system gathered sensor data from various ships, integrated it into a unified map of the battlefield, and allowed weapon operators to receive accurate target information.

Development Background and Reasons

Warships have a compartment called the Combat Information Center (CIC), which collects, organizes, and transmits all the battlefield information the ship is aware of. Information about targets is passed to the CIC from radar and sonar operators, and the CIC crew updates a shared map with this data. The map is used by commanders to guide weapons to specific targets. This system was similar to the British battle command centers, but it was much smaller in scale.

There were two major issues with this system. The first was that each ship had independent information about the battlefield. This caused problems in resource allocation within a task force. For example, a ship with the weapons capable of attacking a particular target might not have been able to identify that target on radar, and conversely, two ships might attack the same target while ignoring others. To address this, additional communication methods like radio or flag signals were required, but this led to a huge increase in the volume of data that needed to be transmitted. The second problem was that the system required too much manpower and space to operate.

In the period after World War II, major navies began to study these issues in-depth, particularly in response to growing concerns over long-range high-speed aircraft conducting coordinated attacks. To counter this threat, the concept of deploying "picket" ships (isolated detection lines) to detect targets in advance was used. The radar information from these pickets was transmitted to other ships, but this was done via voice transmission, which was sometimes unreliable due to interference from waves.

Ultimately, what was needed was a system that could gather target information from any sensor within the fleet, combine it, and present a single integrated picture of the battlefield. Furthermore, this information needed to be transmitted accurately and automatically to all ships. Since the data from electronic equipment and displays made up nearly all the information, a system capable of directly collecting this data via a digital system was ideal.

Previous Systems

The British Navy's early systems, such as the Combined Display System (CDS), were based on analog technology in the post-war period. These systems tracked radar "blips" and used a joystick to adjust target positions and buttons to update information. The circuitry that processed this data was quite complex, but later, it was possible to transmit data to other ships using pulse code modulation (PCM).

However, analog systems were difficult to maintain and prone to errors. In the mid-1950s, advancements in digital computers opened up the possibility of solving these issues. The Canadian Navy's DATAR project was an early digital system based on this concept, but its use of vacuum tubes led to a system that was too large to be miniaturized, and it was eventually discontinued.

System Implementation

The U.S. Navy became interested in these systems as early as 1946, gaining insights from the live demonstrations of the Canadian system, among other development processes. They developed the "Electronic Data System," and by the late 1950s, they began work on a system using transistorized digital computers. With NTDS and wireless data links, ships were able to share data collected from their respective sensors and gain real-time situational awareness of each other's information. In October 1961, USS Oriskany (aircraft carrier), USS King, and USS Mahan (destroyers) were the first test ships to be equipped with NTDS.

Hardware Description

NTDS used a variety of computer systems, including UNIVAC computers. The CP-642A (AN/USQ-20) was a system that processed 30-bit words, had 32K of magnetic core memory, and 16 parallel I/O channels, which were connected to radar and other peripheral devices. This system was water-cooled, and some models were later developed with air cooling.

Modem Description

NTDS information was transmitted between ships via the Collins Radio Kineplex modem. The Kineplex used a parallel multi-tone modem system that enabled efficient transmission of large volumes of data.

Seymour Cray and NTDS

Seymour Cray is known for developing the first processor for NTDS, the AN/USQ-17, although this design was not actually put into production.

Submarine Warfare and Command Control Systems

The ASW Ships Command & Control System (ASWSC&CS) was installed on the USS Voge, USS Koelsch frigates, and USS Wasp aircraft carrier in 1967 as an enhancement to digital submarine warfare. This system was later applied to other submarine combatants. UNIVAC handled both hardware definition and software development.

The AN/UYQ-100 Maritime Warfare Decision Support System (USW-DSS) was the latest iteration as of 2010.