Entry & progression
The sea service is the long pole. 36 months — or 18 months inside an approved and monitored course. Everything is measured in metres of vessel length, never tonnage, even though the certificate is named after a tonnage.
The three numbers
| Requirement | How long | On what | Doing what |
|---|---|---|---|
| The base | 36 months (or at least 18 months if part of an approved and monitored course) | vessels ≥12 m long | watchkeeping duties in the deck department |
| Of which — the big-boat slice | 8 months | vessels ≥20 m long | on voyages of at least 24 hours duration |
| Of which — the understudy slice | 6 months of that 8 | same vessels | as understudy of the officer in charge of a navigational watch |
So the 6 sits inside the 8, and the 8 sits inside the 36. You do not need 36 + 8 + 6. You need 36 months in total, and at least 8 of those months have to be the harder, bigger, longer-voyage kind, and at least 6 of those have to be understudy time under a watchkeeper who is signing for you.
You must also be at least 18 years old. That is the only age gate on the certificate.
Metres, not tonnage
WARNING — Service is measured in METRES, all the way up Every service threshold in MO74 Schedule 2 — at every one of the four grades — is ≥12 m or ≥20 m. There is not a single tonnage figure in the service requirements.
Even Master <3000 GT (Yachts) — a ticket named after a tonnage — asks only for service on vessels ≥12 m, of which 8 months ≥20 m. You never have to have served on a 3000 GT anything. The tonnage in the certificate name describes what you may work on afterwards. The metres describe what you had to serve on before.
This trips up mariners crossing from the merchant ladder, where everything is a tonnage.
The 18-month route
The 36 months drops to at least 18 months if the service is performed as part of an approved and monitored course. That is the cadet-style route, and it halves the hardest requirement on the certificate. It is the single largest lever available to you.
CAUTION — Which courses are approved is AMSA's call — not ours MO74 says approved and monitored course. It does not list them, and AUS_FACTS records no confirmed list. Do not enrol on the strength of a training provider's marketing. Confirm with AMSA, in writing, that the specific course is approved and monitored for the purposes of MO74 Schedule 2 before you spend a year of your life on it.
The quality of the time
MO74 Schedule 3 restricts the role: service must have been performed as a master, deck officer, trainee deck officer, deck cadet or rating. It does not restrict the vessel type or the trade.
But MO70 gives AMSA an express discretion to discount service it considers of little or no relevance, and AMSA has said plainly that service on vessels that spend considerable time in port will not be accepted. A yacht that sat on a dock in Antibes for eight months of the season is exactly the case that discretion was written for. Sea time is time at sea.