Greater Tunb IMINT

Greater Tunb belongs the the trio of islands - including Abu Musa and Lesser Tunb - that Iran occupies, but is also claimed by the UAE. It offers a commanding view of the Strait of Hormuz and is flanked on either side by the primary shipping lanes running through the Persian Gulf, in other words: it is of extreme strategic importance. As a consequence, it is heavily militarized and offers fodder for IMINT (image intelligence) analysis.

Greater Tunb has a total area of 26 sq/km and more hilly geography than either Lesser Tunb or Abu Musa. The island's red, sandy terrain is dotted with vegetation and animal life, relatively lush compared to the barren Lesser Tunb 13 km to the west. A small civilian population, presumably fisherman, may reside on the island but their current status is unclear. In 2001, the total number had declined from 350 in 1993 to 35. (1) Whatever civilian population does reside would likely occupy the cluster of residential buildings on the southern portion of the Island.

Following the islands seizure in 1971 by the Imperial Armed Forces, the Islamic Republic of Iran fortified the islands during the Tanker War. Tensions between Iran and it's Arab neighbors in the early 90s, Iran is reported to have stationed surface-to-air missiles on the island. (2)

For the first time, high quality satellite imagery of the island recently become available on Google Earth. (3) This imagery reveals a highly fortified island with a number of hardened shelters, underground facilities, fighting positions, artillery, and air-defenses.

Ringing the island almost without interruption are earthen fighting positions intended to repulse an amphibious attack. These range from relatively simple revetments on either side of the coastal road with enlarged areas at intervals to packed-earth revetments complete with trenches, strong-points, and reinforced pillboxes. The high-quality of the imagery available sheds light on similar fortifications on other islands whose individual features are harder to discern. The rest of the island is also dotted with various fighting positions of varying ages. Supplementing these fighting positions are guard-posts also located at set intervals around the coast (usually 1-2 km). The buildings are 15 x 15 m and incorporate a watch-tower on the roof. They are often co-located with AAA.

Air defense of the island is typical of Iranian facilities with numerous 23 mm AAA emplacements on concrete pads, usually on raised earthen platforms. Each site is normally accompanied by a small building or hardened shelter for the weapons crew and/or ammunition storage. No evidence of the above-mentioned SAM from the 1990s is visible, however on the north-eastern side is a Skyguard air defense system with two 35 mm guns.

Like on the other islands, the only surface-to-surface weapon actually visible in imagery are a handful of towed artillery pieces. On Greater Tunb this consists of four 122 mm D-30 guns (60% battery) located just west of the Skyguard system. Unlike the other islans though, there is also a second collection of four guns with the conventional split-trail configuration and which are pointed directly towards the waters of the UAE. The specific type of gun is unknown but it is likely 155 mm. At the ranges involved, it's unlikely that these guns would actually be used for fire support on the island, but rather as coastal artillery, either to harass shipping, or to repel an amphibious assault.

Hardened shelters and underground facilities are also a key component of the military garrison on Greater Tunb. While the majority appear to be basic hardened shelters dug into the hillside, or located above ground the storage of munitions and weapon systems as per the style used throughout Iran for the same purpose, there are also a number of sites that possibly hold larger UGFs that could contain command-and-control nodes or even living facilities. The key when differentiating UGFs from hardened shelters is to look for a) relatively few entrances in a specific area, b) the specific style of concrete ramps leading into the entrance, and c) the presence of air-circulation vents.

Other important relevant features include a pier on the eastern side of the island in which a number of small high-speed patrol boats are visible. The small 1,300 m landing strip which has served the island in the past appears to be in the middle of an on-going expansion to 2,200 m. This may indicate a growing effort to increase the strategic importance of these islands in general.



Works Cited:
(1) Great Little Tonbs. The Iranian. May 2001. http://www.iranian.com/GuiveMirfendereski/2001/May/Tonb/index.html
(2) The Iranian, 2001. 
(3) Imagery dates from March 2010.