MV Swift Rescue [RSN] located the fuselage of AirAsia flight

MV Swift Rescue is a Submarine Support and Rescue Vessel (SSRV) that is operated by the Singapore Navy. It was built by ST Marine, a subsidiary of Singapore Technologies Engineering (ST Engineering). The vessel is capable of conducting rescue operations in Sea State 5 conditions. Swift Rescue was launched by the Republic of Singapore Navy (RSN) in November 2008. The vessel is equipped with Submarine Escape and Rescue (SMER) capabilities.
Singapore Navy vessel MV Swift Rescue has located the main wreckage of the downed airplane, with remotely-taken images showing part of the wing as well as the words on the fuselage, Defence Minister Ng Eng Hen says.

January 6 Direct from Stockholm archipelago?   Russians send small sub to search for AirAsia flight]
The Priz class (Project 1855) is a type of Deep Submergence Rescue Vehicle (DSRV) operated by the government of Russia. 

Russian search and rescue team has arrived to take part in search operations for AirAsia flight QZ8501
Russia’s equipment included a remotely-operated submerged vessel that weighs about 500 kilograms (1,102 pounds) and can operate at a depth of as much as 300 meters (984 feet),

[January 5  Tow Fish side scan sonar system on board littoral combat ship USS Fort Worth's (LCS 3) in airasia search ]

NAN HAI JIU 101  IMO number: 9433212

China’s Ministry of Transport says it has sent the rescue vessel “Nan-hai-jiu 101” to help retrieve the black boxes of flight QZ8501. The ship set sail at 10 a.m. Monday from south China’s Haikou City. It is heading for the sea area where the wreckage is located. The ship is expected to arrive there in four days.
Navy Diver 2nd Class Daniel Soulliard, assigned to Mobile Diving and Salvage Unit (MDSU) 1, monitoring the readings from a Tow Fish side scan sonar system on board littoral combat ship USS Fort Worth's (LCS 3) 11-meter rigid hull inflatable boat, on january 5

December 30 2014 USS Fort Worth standing ready to assist in search also China]

USS Fort Worth is docked in Singapore, standing ready to assist in search and rescue operations underway for AirAsia Flight 8501. The Fort Worth, a littoral combat ship, should be ready to join the effort by January 1.   “What its role will be is currently being assessed as circumstances evolve,”
 Helicopter Maritime Strike Squadron 35
China's Defense Ministry said it had sent a warship to the South China Sea and planes "have begun preparatory work" for search operations. 

[December 29 USS Sampson to join search for the AirAsia passenger jet]
USS Sampson was sent December 29 to the search area for AirAsia Indonesia flight QZ8501 from Surabaya to Singapore  that went missing Sunday amid stormy weather off Indonesia.   The 509-foot Sampson (DDG-102) is an Arleigh Burke-class destroyer and is carrying a detachment from Helicopter Maritime Strike Squadron 35, based at Naval Air Station North Island,CA.  Sampson is already deployed in the Western Pacific.  Pentagon officials said that other search and detection capabilities may be used as needed.