Extended Operational and Trade Vocabulary

Maritime Search and Rescue Coordination glossary

The SAR-coordination vocabulary: the Aircraft Coordinator and SMC roles, 406 MHz distress beacons, datum and search-pattern terminology, and the on-scene-coordination and RCC terms under the SAR Convention and the IAMSAR Manual. Grounds each term in the SAR coordination role or the search procedure it belongs to.

410 defined terms.

Showing 250 on this page (page 1 of 2).

A

ACO: Aircraft Coordinator designated by the SMC to deconflict multiple aircraft operating in a SAR incident.
ACO Brief: Standardized pre-mission briefing delivered by the Aircraft Coordinator covering search area, altitudes, and communications.
Active Beacon: A 406 MHz distress beacon that has been manually or automatically activated and is transmitting.
Aerial Datum: Reference point used by SAR aircraft to commence a search pattern.
AFM: Armed Forces of Malta, the national SAR authority operating MRCC Malta in Valletta.
AFRCC: Air Force Rescue Coordination Center at Tyndall AFB, the US inland SAR coordinator.
AgustaWestland AW139: Twin-engine medium SAR helicopter operated by multiple coast guards including the Italian Guardia Costiera.
AgustaWestland AW189: Civil derivative of the AW149 used by Bristow for UK SAR contracts.
AIS Type 14: Safety related broadcast message used for SAR coordination over AIS.
AIS-SART: AIS Search and Rescue Transmitter for survival craft.
Alerting Post: A facility receiving distress alerts and forwarding them to the responsible RCC.
AMSA: Australian Maritime Safety Authority, intervention powers under the Protection of the Sea Act.
AMVER: Automated Mutual-Assistance Vessel Rescue system run by the US Coast Guard, used for SAR coordination and highlighted in the El Faro investigation.
Anchored Drift: SAR datum assumption for an object held by sea anchor under wind and current.
Aoraki Range: Reference geographic feature used by RCCNZ for South Island incidents.
Approach Pattern: The route flown by a SAR aircraft from base to the search datum.
Armada de Chile: Chilean Navy whose Directemar branch coordinates maritime SAR in Chilean waters.
Arrival On Scene: Reported time when an SRU reaches the search area, abbreviated AOS.
ASCC: Aeronautical Search and Rescue Coordination Centre under ICAO terminology.
ASR Aircraft: Air Sea Rescue aircraft, a historical term retained in some national services.
Assistance Entity: Any agency or vessel capable of rendering aid during a SAR case.
Attended Watch: Continuous human monitoring of a distress frequency.
AUSREP: Australian Ship Reporting System, coordinated with chart products of the AHO and Joint Rescue Coordination Centre Australia.
Avincis: Spanish-based helicopter operator group, owner of Babcock MCS aviation businesses.
AW101 Merlin: Three-engine medium-lift helicopter operated in anti-submarine and utility roles by the Royal Navy and Italian Navy.

B

Babcock MCS: Babcock Mission Critical Services, operator of civil SAR helicopter fleets in several countries.
Bahamas Air Sea Rescue Association: Volunteer SAR organization supporting Bahamian waters since 1969.
Baltic Sea SAR Agreement: Regional arrangement among Baltic littoral states for cross-border SAR cooperation.
Base Datum: Initial position used to construct an expanding search pattern.
Beacon Decoder: Equipment that decodes the digital message embedded in a 406 MHz Cospas-Sarsat transmission.
Beacon Registration: National database linking a beacon hex identifier to vessel and owner contact details.
Beam Search: A search subdivision using parallel sweeps aligned along a survivor drift bearing.
Bell 412: Twin-engine utility helicopter used by several coast guards for SAR duties.
Bilateral SAR Agreement: Treaty between two states delineating responsibility within adjoining SRRs.
Block Search: Search pattern subdividing an area into rectangular blocks assigned to multiple SRUs.
Bombardier Q400: Twin-engine turboprop operated by the Canadian Coast Guard for maritime surveillance and SAR.
Brazilian Navy: Marinha do Brasil, whose Salvamar system coordinates SAR within the Brazilian SRR.
Breakdown Assistance: Non-distress aid to disabled vessels, distinguished from SAR response.
Bridge Watchkeeper: The OOW on a merchant ship who maintains GMDSS distress watch.
Bristow Group: International helicopter operator providing UK SAR services under contract to MCA.

C

CALCM: Coastal Authority Liaison Communication Method, used between adjacent MRCCs.
CAMSLANT: US Coast Guard Communications Area Master Station Atlantic in Chesapeake, Virginia.
CAMSPAC: US Coast Guard Communications Area Master Station Pacific in Point Reyes, California.
Canadian Coast Guard: Federal agency operating Canada's icebreaker fleet and providing ice escort and waterway services in Arctic and Gulf of St. Lawrence waters.
Cancellation Message: Broadcast informing vessels that a previously issued distress alert is terminated.
Cardinal Datum: Datum corrected for cardinal direction of wind-driven drift.
Case File: The complete documentary record of a SAR incident maintained by the SMC.
Cause of Distress: The originating event triggering the SAR response, recorded in the case file.
CCG China: China Coast Guard, formed in 2013 by merging four maritime law enforcement agencies.
CES: Crew Evaluation System, a widely used computer based assessment for officers and ratings.
CFR Title 33: US Code of Federal Regulations governing Coast Guard SAR operations.
Channel 16: VHF international distress, safety and calling channel, 156.800 MHz.
CHC Helicopter: Major international offshore helicopter operator headquartered in Texas.
Civil Air Patrol: US Air Force auxiliary providing inland SAR aircraft support.
CMC: Communications Master Centre within larger national coast guard systems.
Coast Earth Station: Land-based gateway connecting maritime satellite distress alerts to terrestrial networks.
Coast Guard Auxiliary: US Coast Guard volunteer organization founded 1939.
COLREGs Rule 17: Stand-on vessel obligations relevant when SAR units maneuver among traffic.
Compatibility Pattern: A search pattern selected for compatibility with available SRU capabilities.
Composite Pattern: Combination of two search patterns used together to maximize probability of detection.
Confirmed Alert: A distress alert verified as genuine following SPOC investigation.
Coordinated Search: Multi-unit search pattern designated CSC in IAMSAR Volume II.
Coordinating Authority: The RCC accepting overall coordination of a multi-jurisdiction case.
Coordinating Surface Search Unit: CSS, the lead vessel coordinating surface SRUs on scene.
COSMOS: Russian-built LEO satellites that historically hosted the Cospas payload.
Cospas-Sarsat: International satellite system for 406 MHz distress beacon detection.
Cospas-Sarsat Council: Governing body of the program comprising representatives of member states.
Cospas-Sarsat Secretariat: Headquarters in Montreal coordinating program operations.
Cross Corsen: French MRCC at Pointe de Corsen covering the western Channel and Iroise Sea.
Cross Etel: French MRCC at Etel covering the Bay of Biscay.
CROSS Gris-Nez: French Maritime Rescue Coordination Centre coordinating SAMU de Coordination Medicale Maritime medical consultations.
Cross Jobourg: French MRCC at Jobourg covering the central Channel.
Cross MED: French MRCC at La Garde covering the Mediterranean SRR.
CRS: Croatian Register of Shipping, IACS member headquartered in Split.
CSC: International Convention for Safe Containers, 1972, governing structural safety of freight containers.
CSE: Continuous service equipment, machinery in continuous use on UMS ships.
CSP: Commence Search Point, the geographic start of a search pattern.
CSS: Coordinator Surface Search, a surface SRU coordinating other surface units.
Current Datum: Datum corrected for ocean current vector since incident time.

D

Danish JRCC Aarhus: Joint Rescue Coordination Centre in Aarhus, Denmark.
Datum: The horizontal or vertical reference frame; ENC horizontal datum is mandatorily WGS-84.
Datum Area: Circular zone of uncertainty around the calculated datum.
Datum Line: Linear datum where survivor position lies along a probable track.
Datum Marker Buoy: Drifting buoy deployed to measure local drift for datum refinement.
DCS: IMO Data Collection System on fuel oil consumption, MARPOL Annex VI, cross-referenced with SOLAS chapter requirements.
Decca SAR: Historical UK SAR navigation aid superseded by GPS.
Deep Tow Sled: Underwater search asset used in subsurface SAR following loss of aircraft.
Defense Search and Rescue: Military-led SAR component coordinated with civil RCCs.
DGzRS: Deutsche Gesellschaft zur Rettung Schiffbruchiger, German sea rescue society founded 1865.
Direct Communication: SMC to OSC voice or data link unmediated by relay stations.
Directemar: Directorate General of the Maritime Territory of Chile, exercising SAR authority within the Chilean SRR.
Direction Finder: Equipment used by SRUs to home on distress transmissions.
Disengagement Phase: Termination phase of a SAR case after rescue or suspension.
Distress alert: GMDSS message indicating grave and imminent danger.
Distress Phase: IAMSAR-defined emergency phase indicating grave and imminent danger.
Distress Priority: Highest priority traffic on GMDSS networks.
Distress Relay: Retransmission of a distress alert by a third party.
Distress Traffic: All communications related to the immediate assistance required by a vessel in distress.
Diversion Capability: A merchant ship's ability to alter course to render assistance.
Diversion Request: Formal SMC request to a ship to leave its track and proceed to a casualty.
Doppler Processing: LEOSAR technique used to locate 406 MHz beacons via satellite passage.
Drift Calculation: Estimation of survivor or debris movement from incident position to datum.
Drift Error: Component of search area uncertainty arising from drift estimation.
DSC: Digital Selective Calling per ITU-R M.493 and ITU-R M.541.
DSC Watch: Automated reception of DSC distress alerts on Channel 70 and other frequencies.

E

EEZ Coverage: SAR coverage extending across a coastal state's Exclusive Economic Zone.
Egyptian Coast Guard: Maritime branch of the Egyptian Armed Forces coordinating SAR in Egyptian waters.
ELT: Emergency Locator Transmitter, automatic 406 MHz distress beacon fitted to helicopters.
Emergency Phase: Generic IAMSAR phase including uncertainty, alert and distress.
Encoded Position: GPS position encoded into a 406 MHz beacon transmission.
End of Operation: Formal SMC declaration concluding active SAR efforts.
EPIRB: Emergency Position-Indicating Radio Beacon required under SOLAS IV/7.
EPIRB-AIS: EPIRB with integrated AIS Message 1 locator (e.g., Ocean Signal rescueME EPIRB3).
Erect Search Pattern: A pattern oriented with the major drift axis.
European Beacon Registration: Regional beacon registration database under Cospas-Sarsat.
Expanding Square: Search pattern code SS commencing at datum and spiraling outward.
Expected Position: Estimated position of a vessel based on last known information.

F

False Alert: Distress signal not corresponding to an actual emergency.
False Alert Procedure: GMDSS procedure for cancelling an inadvertent distress alert.
Falsely Activated Beacon: A 406 MHz beacon transmitting without genuine distress.
FCC Beacon Registry: US Federal Communications Commission registration scheme for 406 MHz beacons, transferred to NOAA.
Federal SAR Plan: US national plan defining federal SAR responsibilities.
Final Position: Geographic location at which a survivor or casualty is recovered.
Finnish Border Guard: National authority operating MRCC Turku for Finnish SAR.
First Light: Earliest time at which visual search becomes effective at dawn.
First Notification: Initial alert received by an RCC that triggers a SAR response.
Fishery Patrol Vessel: Constabulary vessel enforcing fishery laws.
Five Hundred Foot Rule: Standard minimum visual search altitude for fixed wing aircraft.
Fixed Wing SRU: A fixed wing aircraft assigned as a Search and Rescue Unit.
Flag-State Notification: Diplomatic procedure under UNCLOS by which cable repair vessels notify coastal states before operating in their EEZ.
Flank Search: Search variation directed along the flanks of a primary track.
Flight Following: Active monitoring of SAR aircraft progress by ATC or RCC.
Float free EPIRB: 406 MHz beacon under SOLAS.
FocusLight: Designation for searchlight orientation during night SAR operations.

G

Galileo SAR: SAR payload hosted on Galileo MEOSAR satellites by the European Commission.
GEOSAR: Geostationary segment of Cospas-Sarsat providing near-real-time alerting without Doppler position.
German Bight MRCC: MRCC Bremen, the central JRCC for German waters under DGzRS coordination.
GLONASS SAR: SAR payload on Russian GLONASS MEOSAR satellites.
GMDSS: Global Maritime Distress and Safety System under SOLAS Chapter IV.
GPS SAR: SAR payload on US GPS Block IIIA MEOSAR satellites.
Grand Banks SAR: Canadian Coast Guard SAR operations off Newfoundland.
Greek Hellenic Coast Guard: HCG, national coast guard headquartered in Piraeus.
Greenland Joint Arctic Command: JCG, Danish armed forces command coordinating SAR around Greenland.
Ground Segment: Network of teleports, hubs, and operations centers supporting a satellite system.
Guarda Nacional Republicana: Portuguese gendarmerie with maritime unit supporting SAR coordination.
Guardia Costiera: Italian Coast Guard, Corpo delle Capitanerie di Porto, with MRCC Rome.

H

Hamburg Convention: Informal name for the 1979 International Convention on Maritime Search and Rescue.
Hand Held VHF: Portable VHF survival craft transceiver carried in lifeboats.
Hand Off: Transfer of case coordination between adjacent RCCs.
HC-130 Hercules: Lockheed fixed wing aircraft operated by the US Coast Guard for long range SAR.
HCG: Hellenic Coast Guard, the Greek maritime law enforcement and SAR service.
Heading Mark: Geographic feature used by SRU to maintain pattern heading.
HeliService International: German offshore helicopter operator with SAR capability.
Hellenic Rescue Team: Greek volunteer SAR organization supporting state services.
HF DSC: HF Digital Selective Calling on 4207.5, 6312, 8414.5, 12577 and 16804.5 kHz.
HH-60 Pave Hawk: Sikorsky combat SAR helicopter used by US Air Force pararescue.
High Seas SAR: SAR operations outside any coastal state's territorial sea.
Home In: SRU maneuver toward a radio beacon using direction finding.
Homer Equipment: Direction finding equipment installed on SAR aircraft and vessels.
Hong Kong MRCC: Maritime Rescue Coordination Centre operated by the Hong Kong Marine Department.
HRU: Hydrostatic Release Unit releasing the float free EPIRB at depth.
Hypothermic Survivor: Casualty with reduced core temperature requiring specialized recovery.

I

IAMSAR Manual: Joint IMO/ICAO SAR procedures manual.
IAMSAR Volume I: Organization and Management volume of the IAMSAR Manual.
IAMSAR Volume II: Mission Coordination volume of the IAMSAR Manual.
IAMSAR Volume III: Mobile Facilities volume of the IAMSAR Manual.
IBRD: Beacon Registration Database operated by Cospas-Sarsat for beacons without national registry.
ICAO: International Civil Aviation Organization, co-publisher of the IAMSAR Manual.
ICE-SAR: Icelandic Association for Search and Rescue, the national volunteer SAR organization.
ICG: Indian Coast Guard, established 1978, operating MRCCs at Mumbai, Chennai and Port Blair.
IDF Navy: Israel Defense Forces Navy, providing SAR response in Israeli waters.
IMRF: International Maritime Rescue Federation, the global body for SAR organizations.
In Force 1985: Year the 1979 SAR Convention entered into force.
In-scene Communications: Voice or data links among SRUs operating in the search area.
Incident Report: Final documented account of a SAR case prepared by the SMC.
Indian Navy MRCC: Indian Navy coordinated MRCC complementing Indian Coast Guard SAR centres.
Initial Action: First operational response by an RCC upon receipt of an alert.
Inmarsat C: Polling/EGC/SafetyNET service in GMDSS.
Inmarsat SafetyNET: Free broadcast service for medical advice messages.
Intercept Search: Pattern designed to intercept a moving target along its predicted track.
International Cospas-Sarsat Program: Treaty-based program operating the global satellite SAR system.
Iridium SafetyCast: GMDSS Maritime Safety Information service via Iridium.

J

Japan Coast Guard: JCG, the agency under which JHOD operates.
JCG Greenland: Joint Arctic Command coordinating SAR around Greenland.
JRCC: Joint Rescue Coordination Centre handling combined aeronautical and maritime SAR.
JRCC Bodo: Joint Rescue Coordination Centre in Bodo, covering northern Norway and Arctic waters.
JRCC Halifax: Canadian JRCC covering the Atlantic Region SRR.
JRCC Stavanger: Joint Rescue Coordination Centre in southern Norway.
JRCC Trenton: Canadian JRCC covering the Trenton Region SRR.
JRCC Victoria: Canadian JRCC covering the Victoria Region SRR including the Pacific.
JRSC: Joint Rescue Sub Centre, subordinate to a JRCC.

K

KCG: Korea Coast Guard headquartered in Incheon, operating multiple regional rescue centres.
Keepout Zone: Area where SAR overflight is restricted by host state.
Kinematic Search: Search method accounting for relative motion of multiple drifting objects.
KNRM: Koninklijke Nederlandse Redding Maatschappij, Royal Netherlands Sea Rescue Institution since 1824.

L

Land SAR: Land-based SAR distinct from maritime SAR operations.
LEOSAR: Low Earth Orbit segment of Cospas-Sarsat providing Doppler localization.
LES: Large Eddy Simulation, scale-resolving turbulence approach available in STAR-CCM+, Fluent, and OpenFOAM.
LKP: Last Known Position of a vessel or person in distress.
Local Time: Wall clock time at the search area, often referenced alongside UTC in case files.
Locator Beacon: Generic term for 406 MHz distress beacons.
Lockheed P-8: Boeing P-8A Poseidon maritime patrol aircraft used by several navies for SAR support.
Lookout Distance: Maximum range at which a survivor can be visually detected from an SRU.
Loss of Communications: Alert phase triggered by unexplained communication failure with a vessel.
Lyon Mission Control Centre: French Mission Control Centre for Cospas-Sarsat alerts.

M

Major Incident: SAR case involving large casualty numbers requiring multi-agency response.
Manned Watch: Continuous human watch on a designated distress frequency.
Marine Hazard Information: Hazard notices broadcast through NAVTEX and SafetyNET.
Maritime Assistance Service: Coastal MAS distinct from SAR, handling non-distress incidents.
Maritime Coordination: SMC function applied specifically to maritime SAR incidents.
Maritime New Zealand: National maritime authority operating RCCNZ in Lower Hutt.
Maritime Safety Information: MSI broadcast through NAVTEX and SafetyNET.
Mass Rescue Operation: MRO, a SAR response involving large numbers of survivors beyond routine capability.
Master of Distressed Vessel: Person ultimately responsible for the casualty until rescue.
Mayday: Voice radiotelephone distress signal repeated three times.
Mayday Relay: Voice distress relay by a third party on behalf of the casualty.
MCA: UK Maritime and Coastguard Agency, responsible for SOSREP intervention.
MCC: Mean cylinder condition assessment based on scrape-down sampling, inspection, and feed-rate optimization.
MEDEVAC: Medical evacuation by ship, helicopter, or fixed-wing aircraft.
MEDICO: Telemedical advice service for vessels at sea.
MEOSAR: Medium Earth Orbit segment of Cospas-Sarsat on GPS, Galileo and GLONASS, enabling rapid global localization.
MERSAR: Merchant Ship Search and Rescue Manual, the predecessor to IAMSAR.
Mexican Navy SAR: Secretaria de Marina of Mexico coordinating maritime SAR in Mexican waters.
MH-60 Jayhawk: Sikorsky medium range SAR helicopter operated by the US Coast Guard.
MH-65 Dolphin: US Coast Guard short-range SAR helicopter, derivative of Eurocopter AS365.
Mid-Course Datum: Updated datum produced part way through a search.
Minimum Visibility: Visibility threshold below which visual search is suspended.
Mission Control Centre: Cospas-Sarsat node receiving processed alerts from ground antennas.
Mission Number: Unique identifier assigned by the SMC to each SAR case.
Mobile Earth Station: Shipboard satellite terminal in GMDSS architecture.
MPA Singapore: Maritime and Port Authority of Singapore, the regulator licensing bunker suppliers and bunker craft operators in the Port of Singapore.
MRCC: Maritime Rescue Coordination Centre established under SOLAS Chapter V Regulation 7.
MRCC Chennai: Indian Coast Guard MRCC on India's east coast.
MRCC Colombo: Sri Lankan MRCC operated by the Sri Lanka Navy.
MRCC Lisboa: Portuguese MRCC at Lisbon covering the Portuguese SRR.
MRCC Mumbai: Indian Coast Guard MRCC covering western India.
MRCC Piraeus: Greek MRCC at Piraeus operated by Hellenic Coast Guard.
MRCC Rome: Italian MRCC operated by Guardia Costiera at IMRCC Rome.
MRCC Tarifa: SASEMAR MRCC at Tarifa covering the Strait of Gibraltar.
MRSC: Maritime Rescue Sub-Centre operating under an MRCC.
MSI: Maritime Strategies International, the London consultancy.
MV Drift: Vessel drift component of overall datum drift calculation.

N

National SAR Plan: National document defining domestic SAR organization and procedures.
NAVAREA: One of 21 navigational warning areas under the Worldwide Navigational Warning Service relevant to incident broadcasts.
NAVTEX: GMDSS broadcast service under SOLAS IV.
NCSR: Sub-Committee on Navigation, Communications and Search and Rescue of the IMO.
NHV Group: Belgian-based offshore helicopter operator serving North Sea and West Africa.
Nigerian Maritime Administration: NIMASA, the Nigerian agency coordinating SAR in Nigerian waters.
NM Square: Nautical mile square used to delineate search subareas.
NOAA SARSAT: US ground segment operator of Cospas-Sarsat at NOAA Suitland.