Multi-layer search tactics from small rescue craft: How Professional Rescue Academy cuts response time
Iain Hoey
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David Lane, Director of Professional Rescue Academy, explains canine and drone deployments for small craft SAR units, highlighting regulatory standards and tactical planning
Small rescue craft are often the first to reach people in trouble on rivers, lakes, and coastal waters.
Their crews work in unpredictable environments where every minute matters and conditions quickly shift against them.
New research now shows how layered tactics and affordable tools can give search teams a crucial edge.
Water Search and Rescue (SAR) units, particularly those operating small rescue crafts, are challenged when called upon by their tasking authorities to search for and rescue, missing people from waters or in the water margins (shallow waters).
A hazardous environment which needs elevated water rescue competencies from the SAR Technicians.
Those skillsets acquired through specialist courses to operate the rescue boat assets; all whilst wearing full water rescue personal protective equipment.
On-scene search strategy is set using information relating to the circumstances of the case to prioritise and deduce scenarios as to why and where the search is conducted for the lost or missing person.
Water search being a life safety critical situation where, ”submersion [heads under waters] duration of less than 10 minutes were associated with a very high chance of favourable outcome; submersion durations longer than 25 minutes were associated with a low chance of favourable outcomes”.
The UK’s Health and Safety Executive (HSE) and the National Fire Chiefs Council (NFCC) state that rescues of submerged casualties must be conducted only with proper resources, equipment, and training, and from the land, water surface, or by personnel with the right PPE.
Sub-surface rescues are restricted to dive teams, which may not arrive quickly enough for positive outcomes.
Recent figures show 2,409 rescues or evacuations from water in England in the year to March 2024, a 73% increase on the previous year.
The Project
Over the last two years Professional Rescue have conducted a research project of “Multi-Layer SAR” tactics, to improve water borne search, motivated from incident experiences attended within my volunteer water rescue Unit: Wessex Rescue.
A project focussed on SAR primarily from small rescue craft and the shallow water margins.
Aiming to improve water/flood SAR capabilities and thereby rescue within that brief time available for lifesaving missing persons.
Once head under the casualty becomes difficult to locate by human sight.
A task further compromised by nightfall, tide height, water direction and speed, prevalent weather conditions, water turbidity, and stability or otherwise of the craft used as a working platform.
How could the usual foundation methods and tactics be improved? Not to substitute but in support of human behaviour and hydrology knowledge (marine or inland waters) to locate the human in the water.
In context of the SAR acronym L.A.S.T., focussing on ‘Locate’ and ‘Access’, using additional layers working from the given tasks and initial planning point (IPP) we saw the search could be improved.
Crucially for cash strapped SAR units, we propose layers of relatively economically priced accessible tactics or technology, as elaborated below.
With further outcomes achievable of gathering data (information) on the working environment, hazards, tasks and enhance any briefings with visual information.
Also supporting effective recording of the areas and compartments that have been searched and to communicate progress to inform the overall tactical plan.
Then to cast forwards this initial data to the next phase to assist with: ‘Access’ e.g.
a dynamic risk assessment (DRA) and communicate those findings when the casualty is located.
Layers
One layer came directly from a night boat search incident.
Wessex Rescue’s Unit Manager, inspired by his own air scenting search dog and background with, formed a joint Unit project in partnership with ‘Dorset Search Dogs’ (DSD) to develop canine SAR on boats.
This has meant that a cadre of DSD unit technicians have become water rescue and rescue boat helm qualified members of Wessex Rescue in order to safely operate with their K9s on the rescue craft – an outstanding achievement.
Working with SMG (Europe) Ltd., the team used a Garmin GPSMAP side scan sonar and LiveScope Plus System mounted for quick deployment.
Side scan sonar allows responders to search large areas rapidly, identify human-sized anomalies, and store data for later review.
With multiple sonar modes and data-sharing apps, it adds flexibility and efficiency to SAR operations without heavy costs.
This up-to-date CHIRP technology is capable of producing detailed sub-surface images regardless of water clarity and scanning several hundred square metres of sea, lake or river allowing large areas to be searched quickly.
The sonar’s acoustic beam reflects off any objects within the water and the data presented on the SAR operator’s screen.
Where vivid colour images are readily interpreted on the display and stored in the Garmin on a transferable memory card for record keeping.
Having three sonar modes, the Panoptix FrontVü sonar view increases your situational awareness and search capacity by showing up to 91 meters (300 feet) in front of the boat.
A Down mode can explore live views directly under the craft and Perspective mode to see under the water from your perspective in an arc – these modes are switchable giving search flexibility.
The “SAR route from Chart page” can configure any one of three preset search patterns and with route specific data indicated on the screen, all recordable.
Inflatable Rescue Boats (IRBs), like the Arancia, are vital for close quarter rescue work.
However, when undertaking more complex search, greater stability and deck room with storage become a priority for Multi-Layer SAR work given the range of tactics needing to be conducted.
Research identified Roto-Tech Kontra 400 and 450 craft as stable rescue platforms with space for drones, sonar, and K9 operations.
Their design offers robust seakeeping, ample storage, and safe transit for sensitive equipment.
Wessex Rescue like many SAR Units have a CAA Drone Authorisation, whereby UAVs/drones have become a vital part of first response work, providing remote sensing of four main functions in the SAR context: surveillance – providing situational awareness; detection – ability to distinguish an object from the background whether using video or thermal load; recognition – determine what type of object has been detected e.g.
person, bird, buoy, etc.; identification – determine the exact identification of the object.
DJI Mavic and Parrot Anafi drone types have been used from the RotoTech craft’s flat decks.
With AlphaGeo UK Ltd., we trialled the FotoKite Sigma tethered drone.
Which enhances Multi-Layer SAR tactics by providing persistent, hands-free aerial situational awareness and data gathering in challenging environments.
Deployed within seconds and requiring minimal piloting, Fotokite delivers real-time Thermal and Low light video to surface teams, supporting rapid victim location, scene assessment, and coordination.
Its tethered design ensures continuous power and secure data transmission, making it ideal for 24/7 operation in remote, urban or GPS-denied environments.
Increasing operational efficiency and safety during complex SAR missions.
For working underwater AlphaGeo UK Ltd., suggested Chasing’s M2 Pro Max ROV (Remotely Operated Vehicle)*, capable of rapid deployment, underwater search and “rescue”, 360° mobility, 200m depth rating, carry lighting with 4K camera for target perception greater than the human eye.
A single beam sonar was fitted and recovery claw on its grabber arm.
Strengthening the tactics by enabling precise underwater recovery in hazardous or hard-to-access environments.
Its high-definition camera, powerful lighting, and six-thruster omnidirectional control ensure stable navigation in turbid waters and strong currents.
Trials with the Chasing M2 ROV confirmed it could locate and grip weighted manikins underwater, with multibeam sonar making detection straightforward and recovery efficient.
An alternative sonar, a handheld device set up to detect humans in water (used in small craft, or shore-based use), is the Vogt-cte GMBH Aquaeye® from VodaSafe.
They state, “is an advanced portable underwater scanner that uses the latest sonar technology as well as artificial intelligence (AI) to identify sub-surface humans and in waters with poor visibility”.
This device can identify anomalies for rapid investigation, a second generation is due.
Tactics
The ‘Standard Operating Procedures’ for the “Multi-Layer SAR” tactics are still a work in progress.
However, a search focussed by the structured approach from intelligence already gathered, working from a stable boat platform using K9, drone, sonar, TIC, and or ROV, can identify sub-surface “anomalies” – potentially the missing person(s).
Anomalies that require direct investigation and if confirmed as the subject are for immediate rescue (hopefully).
(Or sadly, recovery.) Sub-surface search and rescue missions are time critical operations given human survival time and are often performed in extremely challenging conditions.
Conclusions
The huge 73% increase in rescues or evacuations from water requires viable fast SAR solutions.
Given human head under water survival timescales, dive teams with their prolonged response times are not a sub-surface SAR option.
The majority of inland or inshore rescue craft in the UK have little deck space, therefore no room for effectively operating SAR equipment.
Utilising the larger examples of sonar arrays and ROVs, leaving aside the greater costs, can further compromise stability and available deck space for operating the devices and casualty recovery.
On the face of it, the equipment and boat examples set out here, there is a lot of equipment to conduct Multi-Layer SAR.
However, the use of the kit is logical and straight forwards particularly when almost everyone is at ease with electronic human interfaces like laptops, drone and gaming consoles.
Training covers setup and use of sonar and ROVs, recognising their limitations, marking anomalies, and navigation and search planning from small craft.
Current SAR often involves multiple emergency services and voluntary teams, which is costly and slow to assemble.
Multi-Layer tactics offer a faster, more economical alternative.
The huge advantages are that these “Multi-Layers” are very cost effective.
With up-to-date electronics, compact and readily useable, may be carried and deployed together with the K9 asset, with the possibility of saving lives from one fit for purpose RotoTech craft.
Supported, as per the Codes, by SAR Technicians in another craft for safety backup and rescue purpose.
Allowing interventions to save submerged casualties be conducted with appropriate resources, equipment, training, and adherence to legislation, policy, and procedure.