AMSA
Australian Maritime Safety Authority. The national regulator of commercial vessels, distress beacons, search and rescue, and MMSI allocation.
REFERENCE / 47 TERMS
Skipper glossary
Plain-language definitions for terms you will meet in the course and on the water. Use the related lessons to see each idea in context.
This glossary is a companion to the full course. It explains common nautical and qualification language, but it is not a substitute for current official definitions or practical instruction. Start with the two-system overview, collision rules or AMSA certificates for context.
AMPA
AMSA Mandated Practical Assessment — the practical skills test at the end of a lower-grade commercial course, as distinct from an oral examination.
AusENC
The Australian Hydrographic Office's official electronic navigational chart service.
AWQ
Australian Waters Qualification — the entry-level marine radio certificate, VHF and 27 MHz in Australian waters.
Bar
A shallow, shifting sandbank where a river meets the open coast, across which waves shoal and break. See Chapter 17.
CBDR
Constant bearing, decreasing range — the condition that defines risk of collision under COLREGs Rule 7.
CEVNI
The endorsement to an ICC covering the European inland waterway rules. Required for the French and Dutch canal systems.
Chart datum
The level below which charted depths are measured. On modern Australian charts, Lowest Astronomical Tide.
Cocked hat
The small triangle formed by three position lines that do not quite meet. Assume you are at the corner nearest the danger.
COLREGs
The International Regulations for Preventing Collisions at Sea, 1972. Given force in Australia by Marine Order 30 and by state legislation.
Coxswain
The entry-level Australian commercial deck certificate, in Grades 3, 2 and 1. Grade 1 is the workhorse of the charter and fishing industries.
DCV
Domestic Commercial Vessel — a vessel used for commercial purposes in Australian waters, regulated by AMSA under the National Law.
Dodge tide
A South Australian phenomenon where two tidal constituents cancel near neaps, producing a day of near-flat water.
DR / EP
Dead reckoning (course and distance through the water) and estimated position (DR corrected for tide and leeway).
Drogue
A device streamed from the stern to slow a boat running before heavy weather. Distinct from a sea anchor, which is deployed from the bow.
DSC
Digital Selective Calling — the one-button digital distress alert built into modern VHF sets, sent on Channel 70 with your MMSI and position.
EAC
East Australian Current. Flows south along the Queensland and NSW coast at up to about four knots.
ECL
East Coast Low — an intense, rapidly deepening low that forms in the Tasman close to the NSW coast.
ENG1
The UK Maritime and Coastguard Agency seafarer medical, required for superyacht and other MCA-regulated work.
EPIRB
Emergency Position Indicating Radio Beacon — a 406 MHz satellite distress beacon registered to a vessel. Registration with AMSA is free.
EVDS
Electronic Visual Distress Signal. Accepted in place of flares by some states under conditions; not accepted nationally by AMSA.
Heaving to
Backing the headsail against a reefed main so the boat lies quietly at an angle to wind and sea, creating a slick to windward.
HLTAID011
"Provide First Aid" — the national first aid unit required for every AMSA certificate. Revalidate every three years.
IALA Region A
The buoyage system used in Australia: red to port entering from seaward. The Americas use Region B, which is the reverse.
ICC
International Certificate of Competence — the document European charter companies and inland-waterway authorities ask for. Issued via the RYA.
JRCC
AMSA's Joint Rescue Coordination Centre in Canberra, coordinating search and rescue across Australia's 53 million km² region.
Leeway
The angle a vessel is pushed sideways off her heading by the wind, estimated from the angle of her wake.
LROCP / SROCP
Long Range and Short Range Operator Certificates of Proficiency — the marine radio tickets issued by the Australian Maritime College.
MAR
The national Maritime Training Package. Qualification codes like MAR20324 identify a specific certificate.
Marine Order 505
The AMSA instrument governing domestic certificates of competency, substantially rewritten with effect from 1 January 2023.
MED
Marine Engine Driver — the domestic commercial engineering certificates, Grades 1 to 3.
MMSI
Maritime Mobile Service Identity — the nine-digit identity for a vessel's radio, allocated in Australia by AMSA.
Near coastal
The scope of Australian domestic certificates: Australian waters, not international. Not an STCW qualification.
NUC / RAM
Not Under Command and Restricted in Ability to Manoeuvre — the two vessel statuses at the top of the Rule 18 hierarchy.
PLB
Personal Locator Beacon — a satellite distress beacon registered to a person rather than a vessel.
Rule of twelfths
The approximation that a tide moves 1, 2, 3, 3, 2 and 1 twelfths of its range in successive hours.
RYA
Royal Yachting Association — the British body whose Day Skipper, Coastal Skipper and Yachtmaster certificates are the portable recreational credentials, delivered in Australia by recognised schools.
Scope
The ratio of anchor rode deployed to depth of water. More scope means a flatter pull and better holding.
Significant wave height
The average height of the highest third of waves. The maximum wave can be twice this figure.
Snubber
A nylon line taking the load off an all-chain anchor rode, absorbing shock and quieting the chain.
SSS
Australian Sailing's Safety and Sea Survival course. Two days, valid five years, required for Category 1 offshore racing.
STCW
The international Standards of Training, Certification and Watchkeeping convention. Australian domestic certificates are not STCW certificates.
Task book
The AMSA record in which a supervisor signs off competencies. Reduces required sea service by three to five times.
Transit
Two charted objects in line, giving a position line with no compass error. Used for fixing, steering and checking deviation.
Variation / deviation
The angle between true and magnetic north at a place (variation), and the further error caused by the vessel itself (deviation).
V-sheet
A fluorescent orange sheet with a black V, minimum 1.8 m × 1.2 m, carried as a visual distress signal for searching aircraft.
Yachtmaster
The RYA's senior Certificates of Competence — Coastal, Offshore and Ocean. With a commercial endorsement, the entry to AMSA's sail command stream.