Monday, September 7, 2015

Musical Submarine Rescue Ships

"Sayany" submarine rescue ship in Valletta, Malta - September 3, 2015
[credit" Emmanuel L.]
On August 31, the Russian Ministry of Defense announced that Black Sea Fleet Prut-class submarine rescue ship "EPRON" had departed the Black Sea en route to India for unspecified "international military cooperation" with that country's naval forces. The ship transited the Suez Canal, entered the Red Sea on September 3, and is scheduled to arrive in India in early October. "EPRON" last deployed out of the Black Sea in 2011 to support NATO's Bold Monarch submarine rescue exercise near Spain.

What exactly "EPRON" will do in India and for how long is unknown. With the departure of the Black Sea Fleet's sole fully functional submarine rescue ship, this would appear to indicate no submarine operations will occur in the Black Sea for some time. However, Pacific Fleet Rudnitskiy-class submarine rescue ship "Sayany" is currently in the Mediterranean Sea. It was photographed in Valletta, Malta, on September 3, and there is reason to believe it will head into the Black Sea in the near future.

So, what's really going on?

All of Russia's four fleets have submarine rescue ships in their inventories:

- The Northern and Pacific Fleets each have two Rudnitskiy-class ships equipped with deep-submergence rescue vehicles (DSRV); the Pacific Fleet also has the DSRV-equipped Elbrus-class ship "Alagez". Both fleets also have two DSRVs; however, one of the Northern Fleet's DSRVs is currently undergoing a two-year maintenance cycle at Kanonerskiy Shipyard (St. Petersburg).

- The Baltic Fleet has one DSRV-equipped Kashtan-class ship - SS-750.

- The Black Sea has the "EPRON" and the 100-year-old Kommuna-class ship "Kommuna". While "EPRON" is equipped with a rescue chamber, since 2007 the "Kommuna" has had no equipment capable of bringing stranded submariners to the surface. It is equipped only with small remotely-operated vehicles (ROV) capable of surveying the distressed submarine and providing limited support to rescue operations.

Thus, the Pacific Fleet is the only fleet with two operational DSRVs, and the only fleet capable of deploying it (on board "Sayany") to the Mediterranean Sea. As with the Baltic and Northern Fleets, the Pacific Fleet can continue submarine operations with a single operational DSRV.

"Kommuna" submarine rescue ship with "AS-5" DSRV on board - December 2005
In a July 17 Krasnaya Zvezda article about "Kommuna" was this tell-tale paragraph:

In the future, "Kommuna" will again have rescue work. In the near future, six new diesel-electric submarines will arrive in the Black Sea Fleet, and the safety of their operations needs to be ensured. And so plans for "Kommuna" include receiving a rescue submersible and carrying out rescue ship missions.

"Kommuna" was last equipped with a DSRV (Project 1837-class "AS-5") between 1998 and 2006. In 2007, "AS-5" was transferred to the Baltic Fleet, where it served until being stricken from service last year. The above statement, however, suggests the rescue ship may once again serve as the mothership for a DSRV. And that DSRV may be delivered by "Sayany".

If the Krasnaya Zvezda article is correct in suggesting "Kommuna" will take on the Pacific Fleet DSRV on a permanent basis, that means "Sayany" will return to Vladivostok empty, leaving the Pacific Fleet with only one DSRV. While that may be workable for a short time, it would be impossible to operate submarines were the sole remaining DSRV to be out-of-service, either for routine or unscheduled maintenance, for many months. And while Russian Navy's four newer Project 18551/Priz-class DSRVs can be transported via air, road, and train between fleet areas, that is far from the optimal way of providing submarine rescue support.

Yet, the Pacific Fleet was forced to operate in just this way in 2005-2008 and 2012-2013 when the fleet's two DSRVs took turns undergoing long-overdue repairs and upgrades. And it is under these conditions that the Northern Fleet is currently operating - one operational DSRV, one undergoing upgrades. However, from a geographical perspective, the impact on the Northern Fleet is negligible compared to the Pacific Fleet. The farthest distance between Northern Fleet submarine bases (Kola area and Severodvinsk) is approximately 330 nautical miles. Placing a rescue ship somewhere between those two bases would ensure a DSRV could be on station to support operations near both bases and could arrive at the location of a distressed submarine in less than 10 hours. The Pacific Fleet, on the other hand, has two submarine bases (Vladivostok and Kamchatka Peninsula) that are located nearly 1,200 nautical miles apart. Placing a DSRV-equipped submarine rescue ship at 600 nautical miles from either base means it would not arrive at the location of a downed submarine for nearly 30 hours.

"Igor Belousov" with "AS-40" DSRV on board - May 7, 2015
[credit: Curious]
Enter Russia's newest submarine rescue ship, "Igor Belousov", with the fleet's newest DSRV, Project 18271/Bester 1-class "AS-40". Since leaving Baltiysk in August for Phase 4 of factory sea trials, the "Igor Belousov" crew has been testing the ship's diver chamber and Pantera Plus ROV at design depths in the Atlantic Ocean. After being commissioned, the rescue ship will eventually join the Pacific Fleet, probably in 2016, which means the fleet will once again have two DSRVs in its inventory.

The transfer of the Pacific Fleet DSRV will provide the Black Sea Fleet with a much needed boost in submarine rescue capabilities. With the arrival of the first new Kilo-class submarine in the Black Sea later this month and five more over the next 18 months, the Russian Navy cannot risk supporting its growing undersea arsenal using 1950's technology.