they serve as escorts for anti-aircraft and anti-submarine operations, but they also are able to conduct sea control and striker operations ashore with their tomahawk cruise missiles. The Navy also operates a complement smaller of Freedom-class and Independence-class littoral combat ships (LCS) that can be modularly reconfigured for specific mission sets. Having lacked a frigate since the Oliver Hazard Perry-class was decommissioned, the Navy is in the process of acquiring the new Constellation-class guided-missile frigates (FFG). Finally, the Naval Surface Forces operate 31 amphibious warfare ships to support the Fleet Marine Force and its embarked Marine Air-Ground Task Forces as part of an amphibious ready group or expeditionary strike group. This includes the America-class landing helicopter assault (LHA) ships which can carry U.S. Marine Corps F-35B Lightning II fighters and helicopters, and Wasp-class landing helicopter dock (LHD) ships, which can carry both F-35B fighters, helicopters, and landing craft. These are in addition to the San Antonio-classs amphibious transport docks (LPD), and the Whidbey Island-class and Harpers Ferry-class dock landing ships. Naval Submarine Forces The Naval Submarine Forces (NAVSUBFOR) is often referred to as the "silent service," consisting of 68 commissioned submarines. Los Angeles-class, Seawolf-class, and Virginia-class nuclear-powered attack submarines are capable of performing sea control mission by destroying enemy submarines and surface ships, conducting surveillance and reconnaissance, performing irregular warfare, covert troop insertion, mine and anti-mine operations, and land attack missions with tomahawk cruise missiles. Ohio-class nuclear-powered ballistic missile submarines (SSBN) have the sole mission of being launch platforms for nuclear submarine-launched ballistic missile (SLBM). Each carries 20 UGM-133 Trident II SLBMs. The Navy is currently in the process of procuring the Columbia-class SSBNs to replace the Ohio-class. Some Ohio-class submarines have been converted to cruise-missile submarines (SSGN), capable of carrying 154 tomahawk cruise missiles and deploying 66 special operations forces personnel, such as Navy SEALs. Naval Air Forces The Naval Air Forces (NAVAIRFOR) is the Navy's naval aviation arm, centered around the carrier air wing. The core of the carrier air wing are the Naval Air Forces strike fighter squadrons (VFA), which fly the F-35C Lightning II stealth fighter and the F/A-18E/F Super Hornet. A variant of the F/A-18, the EA-18G Growler is an electronic-warfare aircraft flown by electronic attack squadrons (VAQ) off of carriers or land bases. The E-2 Hawkeye provides carriers with airborne early warning and command and control, while the C-2A Greyhound keeps carriers supplied. The