NSW Sailing & Safety at sea Cheat Sheet by danielgivney

Mayday alert
When in distress and grave and imminent danger.

Mayday x 3
This is yacht {name of vessel} x 3
Mayday {name of vessel}
{MMSI if distress alert sent}
{position of vessel}
{nature of distress}
{number on board}
Over

Pan Pan alert
When you need to send an urgent message but you’re not in imminent danger.

Pan Pan x 3
All ships x 3
This is {name of vessel}
{MMSI if urgent alert sent}
{position of vessel}
{nature of distress}
{number on board}
Over

Note: These limits also apply to vessels under anchor. Marina Berths, Jetties & Swings Moorings do not apply.

One long blast at interval in fog means 'Power vessel making way'. One long blast, followed by 2 short blasts at interval in fog means 'Vessel under sail making way'.

Note: Calculated as averages over 10 minutes. Gusts can be up to 40% higher. Waves may be twice the forecast height.

General rule is you can't moor on anybody's berth without permission from the official channels.