Ship Identification 101

As someone who started off studying naval architecture, then spent time in the Navy and finally ended up in the commercial maritime world, I have realized that containership and tanker are not interchangeable words for a specific vessel.  If it’s a tanker, it’s not a containership, and vice versa.

Maybe you’re thinking right now that I’m a total landlubber-turned-maritime-guy, but seriously, if you’re not IN the commercial maritime industry, I have noticed people often have a hard time distinguishing the difference between the two.

There are a lot of different types of ships out there which ply the world’s oceans, and the following will hopefully help those who don’t know the difference, recognize one from the other:

Crude Oil Tanker

euronav famenne vlcc
Euronav’s 298k dwt Very Large Crude Carrier (VLCC) “Famenne”, image: Euronav

A crude oil tanker’s primary distinguishing characteristic is that it’s generally extremely large and has no crane on it, except for a tiny crane seen amidships.  Piping can also be seen on deck.

Dry Bulk Carrier

File photo of the VLOC 'Vale Sohar' in Nantong, China in January 2012.
File photo of the Very Large Ore Carrier (VLOC) ‘Vale Sohar’ in Nantong, China in January 2012.

In the above photo, that isn’t a tanker, but rather a photo of one of the world’s largest bulk carriers.  The distinguishing characteristic is the same as any other dry bulk carrier – no piping is seen on deck.  Looking closely, you’ll see huge sliding hatches instead.

Containership

MV Maersk Mc-Kinney Moller
MV Maersk Mc-Kinney Moller arrives at the harbour of Rotterdam August 16, 2013, (c) REUTERS/Michael Kooren

If it has containers on deck, you can justifiably call it a containership.

Geared Bulk Carrier

geared bulk carrier cranes macgregor
Image: MacGregor

Ever see a ship with cranes like this? It’s a bulk carrier that has the ability to load and unload it’s own cargo.

LNG Carrier

lng libra Hoegh
LNG Libra, a Moss-type LNG carrier, image: Hoegh LNG

The spherical tanks are the most distinguishing feature of a liquefied natural gas carrier such as the LNG Libra. But it could also be an LPG tanker as well. The letters LNG or LPG will likely be painted on the side of the ship to help you distinguish between the two.

An LNG carrier could also look like this which features a membrane-type LNG containment system, vice the spherical, or Moss-type as seen above:

LNG carrier Nakilat qatargas
Image: Nakilat

Pure Car and Truck Carrier (PCTC)

hoegh st. petersburg autoliners roro
Hoegh St. Petersburg, image: Hoegh Autoliners

A PCTC is a type of roll-on roll-off (RoRo) vessel that is characterized by this hideously ugly, yet completely functional hull design which can carry thousands of trucks and cars.  Very rarely do they tip over.

Dredger

geopotes 14 dredger van oord
Van Oord’s Geopotes 14 trailing suction hopper dredge, image via HdeK/wikipedia

A trailing suction hopper dredge such as Van Oord’s Geopotes 14 has powerful suction booms that are lowered from the side of the ship to suck up whatever is on the seafloor.

Heavy Lift Vessel

blue marlin adelaide lhds heavy lift bae systems
Image (c) Andrew Mackinnon

If you see a big ship carrying another ship on top of it, it’s a heavy lift vessel.

Warship

The guided-missile destroyer USS Sampson (DDG 102) in the Philippine Sea. File photo courtesy U.S. Navy
The guided-missile destroyer USS Sampson (DDG 102) in the Philippine Sea. File photo courtesy U.S. Navy

Distinguishing features: Painted haze grey, likely has a gun on it, superstructure in the middle.

The Offshore Sector

The above was by no means an exhaustive list of the different ship types, but rather a few of the most common and recognizable.  The following are vessels commonly seen in the offshore oil and gas sector:

Platform Supply Vessel (PSV)

blue power ulstein px121
Ulstein PX121, Blue Power, image (c) Ulstein

A platform supply vessel has a closed stern and large open area aft for loading and unloading cargo from offshore facilities.

Anchor Handling Towing Supply Vessels (AHTS)

damen ahts 200 anchor handler
Distinguishing feature: Large winches, open transom and a roller on the stern. The above rendering via Damen.

 Offshore Construction Vessel

ADV Ocean Shield. Photo courtesy Hpeterswald/Creative Commons
ADV Ocean Shield. Photo courtesy Hpeterswald/Creative Commons

Distinguishing feature: Large crane aft for lowering equipment to the sea floor, plus a helicopter landing pad.  May also feature a derrick in the middle of the vessel.

Drillship

Discoverer Americas transocean
Discoverer Americas drillship, Image (c) R. Almeida

Distinguishing feature: Looks like a large ship, but has a derrick in the middle, plus a plethora of cranes and a helicopter pad.

Semi-submersible Drilling Rig

COSL Pioneer semisubmersible
COSL Pioneer, image: COSL

Distinguishing feature: Box-shaped, has drilling derrick in the middle.

Floating Production Facility

tensioned leg platform papa terra p-61 mcdermott
Papa Terra Tensioned Leg Platform (TLP) Image: McDermott

Generally larger than a mobile offshore drilling rig, a production facility may or may not feature a drilling derrick, but will always have flare boom to burn off natural gas. It is also anchored or otherwise attached to the sea floor.

Floating Production Storage and Offloading (FPSO) Facility

maersk curlew fpso
Maersk Curlew FPSO, image courtesy Shell UK

Distinguishing feature: In most cases, FPSOs are former crude oil tankers which have had production facilities added to them. They are anchored and most have large turrets located near their bow about which they rotate with the changing weather and currents.

If you read gCaptain regularly, this is likely pretty elementary stuff, but for those new to the industry, hopefully this gives you a better feel for what’s out there.