Module 1.6 — Watch systems & crew hierarchy

Module 1.6 — Final module, Path 1

How the vessel is organised

A humanitarian SAR vessel operates 24 hours a day, in all conditions, often for weeks at a time. That requires a formal structure — a system for rotating who is responsible, a clear chain of command, and defined roles so that everyone knows what they are responsible for and who they answer to.

Understanding this structure helps you integrate quickly, communicate correctly, and avoid the friction that comes from not knowing how decisions are made or who to go to with questions. It also helps you understand what is expected of you — and what isn't.

What you'll cover

Watch systems — how 24-hour vessel operations are structured
The vessel command hierarchy — who is responsible for what
The SAR team structure — STL, SAR crew, and supporting roles
Rescue set-up — how teams are deployed during an operation

Structures vary between organisations

The structure shown in this module reflects common arrangements across humanitarian SAR NGO vessels. The specific titles, roles, and reporting lines vary between organisations. Your pre-deployment briefing will confirm the exact structure aboard your vessel. What stays consistent is the logic — maritime command, NGO coordination, and SAR operations.

Estimated time

8 minutes — followed by a knowledge check and Path 1 completion

Section 1 of 3

Watch systems

A vessel at sea is never truly off duty. Navigation, safety monitoring, communications, and lookout all continue around the clock. This is managed through a watch system — a rotating schedule that ensures qualified personnel are always on duty without requiring any one person to work continuously.

The most common system is four hours on, eight hours off — giving each watch-keeper two watches in every 24 hours. Some vessels use different arrangements. Your vessel's specific watch schedule will be confirmed at your induction.

A typical 4-on 8-off watch rotation

Time

Notes

00–04

Quietest hours — high fatigue risk, alertness critical

04–08

Dawn transition — visibility improving, lookout intensity increasing

08–12

Briefings, equipment checks, most operational activity starts here

12–16

Peak activity hours — highest traffic, most rescues

16–20

Evening, handover preparation, dinner rotation

20–00

Night operations preparation, transition to reduced visibility

What a watch involves

Bridge watch

The Officer of the Watch (OOW) is responsible for navigation and vessel safety during their watch. They have full authority on the bridge. The Master is always contactable but may not be physically present. 24/7.

Engine room watch

Engineers monitor propulsion, power generation, and vessel systems continuously. Most vessels run an engine room watch 24/7. Alarms and pressure changes are monitored in real time.

Bridge lookout (SAR zone)

When the vessel is in the SAR zone, dedicated lookouts are rostered to scan the sea for vessels in distress. Visual, continuous, and rotated frequently to manage fatigue. This is a focused task — no phones, no distractions.

Care watch (survivors aboard)

When survivors are aboard, a care watch runs in the shelter areas — monitoring welfare, supporting the post-rescue team, and alerting medical staff to changes. Rostered 24/7 while survivors are on the vessel.

Handover

When one watch ends and another begins, a formal handover takes place. The outgoing watch briefs the incoming watch on vessel status, weather, any incidents, and anything requiring attention. Always arrive early for your watch.

Standing orders

The Master's standing orders are permanent instructions that apply to every watch — what to do in specific situations, when to call the Master, speed and course constraints. All watch-keepers are responsible for knowing and following them.

Rest is part of your job — and so is helping

The watch system only works if crew actually rest during their off-watch periods. A fatigued crew member makes mistakes. Eat during meal times, sleep during off-watch hours, and manage your energy deliberately. That said — on a vessel, everyone helps each other out. Being off-watch doesn't mean being unavailable. If a rescue kicks off or survivors need care, crew step up regardless of what role they're technically assigned to. It's part of how ships work.

Section 2 of 3

Vessel command hierarchy

A humanitarian SAR vessel has two overlapping structures — the maritime command structure that runs the vessel, and the NGO structure that manages the humanitarian mission. Understanding both, and how they interact, helps you understand who to go to for what.

Maritime command

Master

Captain

Absolute authority over the vessel and everyone aboard — regardless of NGO role or seniority. Responsible for the safety of the vessel, crew, and everyone on board at all times. At sea, the Master's decisions are final. Legal and operational authority rests entirely with the Master.

Chief Officer

1st Officer / C/O

Second in command of the vessel. Responsible for deck operations, cargo, stability, and crew safety. Acts as Master when the Master is off the bridge. Often manages the deck crew directly.

OOW

Officer of the Watch

Responsible for the safe navigation and operation of the vessel during their watch. Has full authority on the bridge during that watch. Never interrupt an OOW during a manoeuvre, docking, or radio communication without urgent reason.

Bosun

Boatswain

Leads the deck crew on a day-to-day basis. Responsible for the maintenance and readiness of deck equipment, lines, and rigging. Often the most experienced practical deck operator aboard. A key person to know as a new crew member.

NGO coordination structure

Head of Mission

HoM

Leads the NGO team aboard — responsible for the humanitarian mission, team management, communications with headquarters, and coordination with the Master on operational decisions. Works closely with the Master but has separate authority over NGO staff.

SARCO

SAR Coordinator

Coordinates SAR operations — works closely with the Master, the STL, and MRCC during rescue responses. Manages communications with maritime authorities and coordinates the overall rescue response alongside the bridge.

Two structures, one vessel

The maritime structure (Master → Officers → Bosun) and the NGO structure (HoM → SARCO → SAR team) operate in parallel. For anything related to vessel safety and navigation, the maritime command is the authority. For the humanitarian mission, team management, and operations coordination, the NGO structure applies. In practice they work closely together — the Master and HoM make joint decisions during rescue operations.

Section 3 of 3

The SAR team

The SAR team is the operational rescue unit aboard the vessel. They plan, prepare, and execute rescue operations — from RHIB deployment to survivor recovery. The structure below reflects common arrangements across humanitarian SAR NGOs; your specific organisation's structure may differ in titles or reporting lines.

SAR team structure

SAR Team Leader
STL

The senior operational SAR authority aboard. The STL leads rescue operations on the water — typically on the lead RHIB during a rescue — and manages the SAR team's readiness, equipment, and training. Works closely with the Master, HoM or SARCO during planning and with the bridge during operations.

SAR Crew

Also: SAR Officers, SAR Technicians

Trained rescue operators who crew the RHIBs and work the deck during rescues. Titles vary by organisation — SAR Crew, SAR Officers, SAR Technicians — but the role is the same: operating the rescue boats, recovering survivors, and supporting the STL. SAR crew are distinct from general deck crew; their role is specifically rescue operations.

NGO coordination structure

Overall NGO mission coordination varies: some organisations have a Head of Mission (HoM), others have a SAR Coordinator (SARCO) who fulfils an equivalent role. Under them sit the SAR team, medical team, post-rescue team, and other operational functions. Your organisation's induction will clarify the specific structure.

Rescue set-up — how teams are deployed

During a rescue, the SAR team deploys across two RHIBs. The specific set-up varies by organisation and operation, but a common arrangement is:

RHIB 1 — STL's boat	RHIB 2
STL Leads on-water operations	RHIB Leader Leads RHIB 2
Cultural Mediator First contact and communication	Driver
Driver	SAR Crew
SAR Crew

Other roles during rescue operations

During a rescue, many other team members play critical supporting roles — medical staff preparing to receive survivors, cultural mediators ready at the boarding point, protection officers managing the shelters, and logisticians distributing supplies. Understanding where you fit in this wider picture is part of your pre-deployment preparation. Your team leader will brief you on your specific role.

Post-rescue team leader

Some vessels have a dedicated Post-Rescue Team Leader (PRTL) who takes over responsibility for survivor management once people are aboard — coordinating the distribution of food, water, clothing, and medical referrals, and overseeing the welfare of survivors in the shelters. This role allows the SAR team to focus on the next rescue while survivor care continues.

Knowledge check — Path 1 final module

Before you complete Path 1

Five questions on watch systems, hierarchy, and the SAR team structure.