Safety near commercial vessels

Taking a little boat near big ships for a close look is like standing on the runway to watch a jumbo jet take off - dangerous for all involved. If a collision occurs it can result in damage, injury or even death, and potentially legal action.

What you need to know

Commercial vessels operate 365 days a year, 24 hours a day.

The speeds of large vessels can be deceptive and they may travel at speeds in excess of 20 knots.

To stop can take up to one or two kilometres for a large ship, even with its engines going full astern.

Large ships can't see you. Their 'blind spot' can extend for many hundreds of metres, even up to one kilometre, in front of them.

Large vessels must keep up speed in order to steer and they need to stay in the channel. Sometimes the channel extends bank-to-bank so expect large vessel traffic on all parts of the waterway, such as Outer Harbour and upper sections of the Port River.

It is dangerous and difficult for large vessels to change course. They must line up and commit to their course well ahead around bridges, bends in the channel and when leaving and approaching their berth. Stay out of their way.

The powerful engines of big ships and tugs can pull small vessels toward them when passing alongside or close to the middle of the ship.

Water turbulence can be dangerous and large vessels cause:

  • prop or wheel wash - a strong underwater current caused by tug or ship engines that can result in severe water turbulence hundreds of metres behind a large vessel
  • bow waves - large surface waves caused by the bow of a ship pushing through the water. A bow wave can swamp small craft hundreds of metres away from the ship.

What to do

Assign one person on your boat to maintain a lookout, particularly for large vessels.

Stay clear of parked or moored vessels when they are berthed at wharves or loading areas, turning areas or terminals.

Watch for large vessels' lighting at night. Don't rely on trying to hear a vessel approaching. If you see both sidelights (red and green) you're dead ahead, and in the path of danger.

What not to do

Don't sail near large vessels. It can be hazardous, as a large vessel can 'steal your wind' and prevent your ability to manoeuvre.

Don't boat, ride a personal watercraft, sail or windsurf in or around large vessels. Jumping wakes, riding close alongside, or cutting under the bow of a large vessel could cause a boat or skier to be sucked through the vessel's large propellers and bow or stern thrusters.

Never pass closely behind a tugboat. A tug could be towing a barge, or other objects on a long submerged line. This tow line may lie low in the water and be difficult to see.

Know your boating rules

Understand whistle signals. Five short blasts on the whistle (about one second duration) indicates that the vessel is unsure of your intentions or doubts that you are taking enough action to avoid collision. Move clear of vessels sounding this signal.

Use safe anchorages. It is illegal and dangerous to tie up to navigation aids like buoys and channel markers, and to anchor in channels.

Cross channels only when safe to do so. Do not impede the passage of a vessel which can only safely navigate within a shipping channel. Try to cross the channel at the shortest possible distance.

When operating at night or in times of restricted visibility make sure that your boat displays appropriate navigation lights. The radars of large vessels are limited in their ability to detect small craft and do not detect wooden or fibreglass vessels.

Be aware of local rules. Restrictions and port operating rules may differ at each port. It is your obligation to be aware of any local restrictions or rules when you are boating in or near harbours and ports.

Ships, tugboats and port control use VHF radio to communicate. If you are unsure of your situation, or a vessel's intentions, feel free to contact them:

  • port operations and ship-to-ship traffic is conducted on VHF Channel 6, 8 and 12.
  • emergency communication is conducted on VHF Channel 16 within port limits.

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Page last updated 18 August 2020

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