SCANFAR

The Hughes SCANFAR system was the first deployed United States Navy phased array radar system installed on the USS "Long Beach" and USS "Enterprise". It consisted of two search radars, the AN/SPS-32 and the AN/SPS-33. In 1982, the system was removed from "Long Beach", and was replaced by the AN/SPS-48 during a comprehensive overhaul. [http://www.usslongbeach-assoc.org/Milestones.html] Despite its failure, the lessons learned were applied to the AN/SPY-1 radar and Aegis combat system. Aboard the Long Beach, the system used AN/SPG-55 radars for missile guidance.

History

Prior to the development of SCANFAR, the Navy had been developing an advanced anti-aircraft weapon system combining an extremely advanced radar system, the AN/SPG-59, with a new long-range missile known as Typhon. The radar acted both as a long-range surveillance system as well as the target illumination and guidance system for the missiles. The system proved to be beyond the state of the art, in particular the radar required a larger number of individual broadcast elements that proved to be unreliable and expensive.

SCANFAR was to some extent a "cut down" version of the SPG-59. The main radar would be used solely for surveillance, target illumination being left to existing radar systems used with earlier missiles like the Talos or Tartar. During development it was found that attempting to use a single antenna for both search and track did not work effectively, so the system was modified to use two antennas, one for surveillance and another for tracking. The overall weapon system ended up using three radar antennas, and was therefore similar to earlier systems.

In service the system proved to be extremely unreliable, due largely to the huge number of tubes it used. Although the "air picture" it provided was good, the low availability rate meant both "Long Beach" and "Enterprise" were unavailable for fleet operations for extended periods. During overhauls the SCANFAR system was removed, and replaced with more "conventional" systems.

*AN/SPS-32 was a wide rectangular antenna for air surveillance.
*AN/SPS-33 was a narrow rectangular antenna for target tracking. According to Navy documentation, the AN/SPS-33 was frequency scanned in elevation and phase scanned in azimuth. [http://www.fas.org/man/dod-101/navy/docs/fun/part07.htm]

References

*Dranidis, Dimitris V. " [http://www.harpoonhq.com/waypoint/articles/Article_044.pdf Shipboard Phased-Array Radars] ". Waypoint Magazine. February 2003. (Written to support wargames, but informative.)

External links

* [http://www.defence.co.kr/weaponbook/weapon/cgn9.htm Weaponbook] - Non-English, but contains a couple of good pictures of the USS Long Beach with the SCANFAR radars.
* [http://64.233.167.104/search?q=cache:h1OJiJ-OE5IJ:www.edefenseonline.com/article.asp%3Fprint%3D1%26idarticle%3D1191+SCANFAR+radar&hl=en&gl=us&ct=clnk&cd=2 Google cache of eDefense Online article]