Type 984 was a
Royal Navy radar system introduced in the mid-1950s, designed by the
Admiralty Signals and Radar Establishment
The Admiralty Signal and Radar Establishment (ASRE) originally known as the Experimental Department and later known as the Admiralty Signal Establishment (ASE) was a research organisation of the British Royal Navy established in 1917. It exist ...
.
Type 984 was a
3D S band
The S band is a designation by the Institute of Electrical and Electronics Engineers (IEEE) for a part of the microwave band of the electromagnetic spectrum covering frequencies from 2 to 4 gigahertz (GHz). Thus it crosses the convention ...
system used for both
ground controlled interception (GCI) and as a secondary
early warning system. It was the most sophisticated naval radar of its era.
Description
The Type 984 was different from most radars in a number of ways. For one, it used a lens made of metal tubes in place of the more traditional
parabolic reflector, which made it look a circular plate rather than the open framework typical of the era. It was mounted on a fully stabilized platform, allowing it to produce a steady image in all but the highest sea states. It also used a unique system for vertical scanning, feeding the output of four
cavity magnetrons into four moving
feedhorns, each scanning about 5 degrees vertically. Other 3D radars of the era generally picked one solution or the other, using a network of separate feedhorns or a single vertically scanning feed. The use of four magnetrons gave it better range performance; against large high-flying aircraft it had a typical range of , although this fell to as short as against small low flying aircraft.
A key part of the overall Type 984 installation was the
Comprehensive Display System
The Comprehensive Display System (CDS) was a command, control, and coordination system of the British Royal Navy (RN) that worked with the detection/search Type 984 radar. The system was installed on a total of six ships starting in 1957. The US ...
(CDS), an
electromechanical computer that developed "tracks" for aircraft in a semi-automated fashion. This greatly reduced operator workload, allowing the overall system to track many dozens of formations of aircraft while continuing to scan for new contacts, what would today be known as
track while scan (TWS). In several tests against
US Navy aircraft during
military exercise
A military exercise or war game is the employment of military resources in training for military operations, either exploring the effects of warfare or testing strategies without actual combat. This also serves the purpose of ensuring the com ...
s, the combination of the 984's high scanning rates and the CDS' tracking made the ships impossible to approach without being intercepted. CDS also allowed the 984 to be used both for interception control, as well as day-to-day
air traffic control around the fleet
aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a ...
s.
The original design called for a maximum weight of , and a maximum turning circle while scanning of . Many Navy designs of the early 1950s intended to mount the 984, and some sported two installations, fore and aft. As the design matured its weight continued to grow, ultimately reaching , making it too heavy for most ships. At the same time, the Navy's inventory of large ships was shrinking. Ultimately it was mounted on only the aircraft carriers , and .
References
External links
*
* {{Cite web
, title=Type 984: A massive radar which only the might of a carrier could carry
, website=HMS Collingwood Collection
, url=http://www.rnmuseumradarandcommunications2006.org.uk/TYPE_984.html
, archiveurl=https://web.archive.org/web/20170808083148/http://www.rnmuseumradarandcommunications2006.org.uk/TYPE_984.html
, archivedate=8 August 2017
Naval radars
Cold War military equipment of the United Kingdom
Royal Navy Radar
Military equipment introduced in the 1950s