Thursday, July 12, 2007

The S-25 SAM System: A Site Analysis

INTRODUCTION

Locating strategic SAM sites in Google Earth imagery is a time-consuming process. Each panel of high-resolution imagery must be scrutinized and examined in order to locate and identify various site configurations and missile systems. In order to ensure success, the analyst must first know what to look for. This is the first article in a multi-part series which will detail the layout and key features of various identifiable strategic SAM sites found worldwide. Armed with this knowledge, the analyst will be able to positively identify such facilities with greater ease and accuracy.

THE SA-1

The first operational strategic SAM system in the world was the Russian S-25 (SA-1 GUILD). The S-25 was a rail-launched system emplaced at fixed launch sites. The command-guided V-300 missile had a maximum range of 45 kilometers, and a maximum reach of between 4,000 and 14,000 meters in altitude. A 250kg HE warhead was fitted. The E/F band R-113 (GAGE) radar provided target acquisition to a range of 300 kilometers. The E/F band B-200 (YO YO) radar performed target engagement functions, with a maximum range of 150 kilometers and the ability to track between 24 and 30 targets per radar. Each B-200 radar could prosecute one engagement at a time.

SA-1 DEPLOYMENT

The S-25 system was conceived to provide air defense of the skies over Moscow. The system was intended to provide defense against an incoming bomber force of 1,000 aircraft. S-25 sites were located in two rings around Moscow, with radii 45 and 80 kilometers from the center of the city.

The image below depicts the locations of the 34 outer ring sites and the 22 inner ring sites:


Initial CIA projections, shown in the image below taken from the declassified NIE 11-5-57, were not that far from the mark:


A TYPICAL SA-1 SITE

CIA NIE 11-5-57 provides us with the following description of an active S-25 site:


The overhead image below depicts a typical S-25 site as it exists today, with the relevant areas and structures annotated:


This site is a rarity insofar as it has remained mostly intact, allowing the site layout to be studied using present-day imagery. The S-25 sites all followed the same standard layout seen above. The radar position, seen below, was located approximately 1.5 kilometers behind the launch area. Two B-200 radars were positioned in the forward area of the bunker, which housed the command and control section and the crews who controlled the site.


The launch area, seen below, contained the individual launch positions. Each launch area contained three V-300 fixed launch assemblies. Each S-25 site contained a number of launch areas. The interlocking nature of the launch areas gave the S-25 sites their distinctive rectangular herringbone appearance.


Adjacent facilities, as seen in the following image, included housing areas for assigned personnel, and support facilities for maintaining the site itself:


All of the site areas were connected using concrete roads. As these roads still exist carving their tell-tale herringbone path through the forested areas outside Moscow, former S-25 sites are relatively easy to locate and identify.

The expansive nature of the S-25 sites also allows them to be easily identified using low-resolution imagery, as evidenced by the image below:


CURRENT STATUS

As the S-25 has since been replaced by different variants of the S-300P family, there are no active sites located in Russia. The sites themselves do still exist for the most part, and many have been reused for other purposes.

The S-25 site seen below has been reused as a residential area, a relatively simple proposition thanks to the aforementioned interconnecing network of concrete roads found throughout the site:


Alternatively, many S-25 sites have been reused by the Russian defense establishment. Quite a few sites, including the site shown above, feature active S-300P SAM batteries. Other sites have formed the basis of the sites for the exoatmospheric component of Moscow's ABM network over the years. For more information and descriptions of these facilities, reference the relevant article found at this site.

SOURCES

-Satellite imagery is provided courtesy of Google Earth
-The CIA FOIA website at http://foia.cia.gov provided the documents shown and referenced above
-Jane's Land Based Air Defence provided technical specifications

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