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We are frequently asked what the hull designation letters DD and FF stand for and whether they are abbreviations.

Some believe, incorrectly, that FF stands for Fast Frigate. It does not. Compared to destroyers, while fast enough to do their assigned tasks, frigates are not fast. The designations are simply because the navy uses a minimum of two letters to designate a ship type.

For example, battleships are BB and auxiliaries such as fleet oilers and ammunition ships are AO and AE, respectively. When both tasks are combined into one vessel it is an AOE. Nuclear-powered vessels will have the designator “N” as the final letter.

To aid in identifying the types here is a partial list that includes the more common ship types:

Hull DesignationDescription
CV, CVA, CVNAircraft Carrier
CVEEscort Carrier (sometimes called jeep carriers)
CAHeavy Cruiser
CLLight Cruiser
CGGuided Missile Cruiser
DD, DDE, DDK, DDRDestroyer
DDGGuided Missile Destroyer
DLDestroyer Leader
DLGGuided Missile Destroyer Leader
DE, DERDestroyer Escort
DEGGuided Missile Destroyer Escort
EDDExperimental Destroyer
FFGGuided Missile Frigate
LCSLittoral Combat Ship
SS, SSN, SSBN, SSGNSubmarines (B=Ballistic Missile)

There are many types of Landing Craft, Patrol Vessels, and Auxiliaries.

Amphibious and Landing Vessels

Hull DesignationDescription
AGC/LCCAmphibious Force Command Ship
AKA/LKAAmphibious Cargo Ship
APA/LPAAmphibious Transport
APDHigh Speed Transport
LPRAmphibious Transport, Small
AFS/LFRInshore Fire Support Ship
LCG(L)Landing Craft Guns (Large)
LCILanding Craft Infantry
LCS(L)(3)Landing Craft Support (Large) (Mark 3)
LSSLLanding Craft Support, Large
LCTLanding Craft Tank
LCULanding Craft Utility
LHAAmphibious Assault Ship (General Purpose)
LHDAmphibious Assault Ship (Multi Purpose)
LPDAmphibious Transport Duck
LPHAmphibious Assault Ship (Helicopter)
LSDLanding Ship Dock
LSMLanding Ship Medium
LSM(R)Landing Ship Medium (Rocket)
LSTLanding Ship Tank
LSVLanding Ship Vehicle

Auxiliary and Service Vessels

Hull DesignationDescription
ADDestroyer Tender
ARRepair Ship
ARBBattle Damage Repair Ship
ARCCable Repairing/Laying Ship
ARGRepair Ship Internal Combustion Engine
ARHRepair Ship Heavy-hull
ARLRepair Ship Landing Craft
ARSDSalvage Lifting Vessel
ARSTSalvage Craft Tender
ARVRepair Ship Aircraft
ARVHRepair Ship Aircraft, Helicopter
ASSubmarine Tender
ACSCrane Ship
AKCargo Ship
AKDCargo Ship Dock
AKLCargo Ship Light
AKNCargo Ship Net
AKRCargo Ship Vehicle
AKSGeneral Stores Issue Ship
AKVAircraft Transport
AGMiscellaneous Auxiliary
AGDSDeep Submergence Support Ship
AGEHHydrofoil Research Ship
AGEREnvironmental Research Ship
AGFCommand Ship
AGMMissile Range Instrumentation Ship
AGMRMajor Communications Relay Ship
AGOROceanographic Research Ship
AGOSOcean Surveillance Ship
AGPMotor Torpedo Boat Tender
AGR (YAGR)Radar Picket Ship
AGSSurvey Ship
AGSCCoastal Surveying Ship
AGTRTechnical Research Ship
AEAmmunition Ship
AFStores Ship
AFSCombat Stores Ship
T-AKEDry Cargo/Ammunition Ship
AOFleet Oiler / Underway Replenishment Oiler
AOEFast Combat Support Ship
AOGGasoline Tanker
AORReplenishment Fleet Tanker
APBSelf-propelled Barracks Ship
APCCoastal Transport
APHEvacuation Transport
APMMechanized Artillery Transport
APVTransport and Aircraft Ferry
ARSRescue and Salvage Ship
ASRSubmarine Rescue Vessel
ATFleet Tug
ATAAuxiliary Fleet Tug
ATFFleet Ocean Tug
ATOFleet Tug (Old)
ATRRescue Ocean Tug
ATSSalvage and Rescue Ship
AVSeaplane Tender
AVBAdvance Aviation Base Ship
AVDSeaplane Tender, Destroyer
AVMGuided Missile Ship
AVPSmall Seaplane Tender
AVSAviation Stores Issue Ship
AVTAuxiliary Aircraft Landing Training Ship
AZLighter-than-Air Aircraft Tender
ABCrane Ship
ADGDegaussing Ship
AHHospital Ship
ANNet Laying Ship
AOTOil Transporter
AWDistilling Ship
HSVHigh Speed Vessel (HSV)
IXMiscellaneous Unclassified (USS CONSTITUTION is an example)

Mine Warfare Vessels

Hull DesignationDescription
ACMAuxiliary Minelayer
AMcCoastal Minesweeper
AMCUCoastal Minesweeper (Underwater Locator)
AMSMotor Minesweeper
BYMSBritish Motor Minesweeper
CMcCoastal Minelayer
DMLight Minelayer
DMSHighspeed/Destroyer Minesweeper
MCMMine Countermeasures Ship
MCSMine Countermeasures Support Ship
MHCCoastal Minehunter
MMCCoastal Minelayer
MMDFast Minesweeper
MMFFleet Minelayer
MSCCoastal Minesweeper
MSC(O)Coastal Minesweeper (Old)
MSFFleet Minesweeper
MSIInshore Minesweeper
MSOOcean Minesweeper
MSSMinesweeper (Special Device)
SMMinelaying Submarine
YMSAuxiliary Motor Minesweeper

Patrol Craft

Hull DesignationDescription
PCPatrol Craft Coastal
PCSubmarine Chaser (173′)
PCEPatrol Craft Escort
PCERPatrol Craft Rescue Escort
PCHSubmarine Chaser (Hydrofoil)
PCSPatrol Craft Sweeper
PEEagle Class Patrol Vessel
PFPatrol Frigate
PGHGunboat (Hydrofoil)
PGMMotor Gunboat
PHMPatrol Combatant-Missile (Hydrofoil)
PRRiver Gunboat
PTMotor Torpedo Boat
PTCMotor Boat Submarine Chasers
PYPatrol Yacht
PYcCoastal Patrol Yacht
SCSubmarine Chaser (110′)