RV Tangaroa is NIWA’s main research vessel – 70 metres long, nearly 14 metres wide and with a 7 metre draft (the depth of the vessel's keel below the waterline). She (all ships are called ‘she’) carries a maximum of 44 people – on this voyage to the Ross Sea, there were 26 science personnel and the remainder were crew. On a voyage, the ship carries enough fuel and food for 60 days. There were no restrictions on freshwater as the ship produces its own – mind you, with 44 on board, we did have to watch usage, as lots of slow running or being stopped on station meant we might not produce enough water to maintain supplies.
For safety in the Antarctic environment, the ship is equipped with sufficient emergency gear for all the ship’s personnel to survive on shore for several days.
We had a fully equipped hospital and, for this trip, carried a doctor. The deck officers were all experienced in ice operations but for added safety we carried an ice pilot – a deck officer with years of experience in Antarctic ice navigation. The Tangaroa has an ice rating, which allows it to break through 0.3 metres of year-old sea ice and push older floes out of its path, but we limited our ice contact wherever possible. Regular ice coverage maps and weather forecasts were supplied to the ship to assist in our survey operations.
Read more about how multibeam echo-sounders generate GIS information to create images of the seafloor on:
IPY blogs week 1
The deck crew work 24/7 in two watches, each with 4 men, midnight to midday and midday to midnight. As we travel to Antarctica, we prepare nets and scientific equipment, lay down rubber matting to reduce the danger of slipping on ice build-up. We close up vents to keep the ship warm. At night, we stand watches on the bridge. From 60° south, we keep 24-hour watch for icebergs (remember the Titanic). Most of the deck crew have been to Antarctica before and the ones that haven’t will soon find out just how cold it can get.
Written by Edmund Fox
Controlling the ship
The Tangaroa moves like a giant skateboard 70 metres long and weighing 3,000 tonnes. The Officer of the Watch in the navigation bridge moves a small wheel, the size of a peanut butter jar lid, to turn the ship, but most times the ship follows a preprogrammed course using the automatic pilot. Pushing or pulling a lever the size of a biro makes the ship stop, move forward at 15 knots, or move astern (backwards) at 8 knots. A knot is a nautical mile per hour. A nautical mile measures 1,854 metres.
Written by Andrew Leachman
Through the eye of the engineer
A vessel’s needs are many and varied but the main one is to set sail and come home again safe and sound. The two engineers keep things ticking over, but without the assistance of the crew working as a team, this couldn’t happen. Diesel fuel keeps our engines and generators running. The engineers also have to be electricians, plumbers, welders, fitters, washing machine repairers and generally Mr Fix-it guys. The general store is usually a long way away. The challenges placed in front of the engineers keep things interesting and there are seldom dull moments.
Written by Lindsay Battersby
Vessel and sampling gear
The Tangaroa carries 3 other craft – the 10.5 metre survey boat Pelorus and two rigid inflatables. Winches with wire lengths of up to 10km cover all our other research tasks, such as towed nets for collecting fish, sleds/dredges for bottom dwelling animals, a multicorer for samples of seabed organisms and nets for sampling of plankton and living animals in the water column. On this trip, we are carrying a wide range of sounders including fish finders, full ocean depth echo-sounders and a multibeam sounder; sampling gear like a CTD (conductivity, temperature, depth) recorder to measure salinity and temperature and to collect water samples; and various underwater camera systems.
Written by John Mitchell
On board are several laboratories dedicated to running equipment and experiments. On the trawl deck on top, we have a dry lab with computers, plankton nets and underwater cameras; a plankton lab; an area where animals from the seafloor are sorted, identified and preserved; and a sterile lab for preparing samples for bacterial work. On the factory deck, we have a wet lab where fish are measured and identified and samples are taken, the constant temperature lab for bacterial work and -30°C and -80°C freezers for sample preservation. The lowest deck below the waterline contains the ship’s computer system and multibeam echo-sounder. But the biggest research laboratory of all is the Ross Sea.
Written by John Mitchell