SONABLOW —
fire by sound, not by wire.
An underwater acoustic firing device that replaces the fragile electric firing line with an encrypted acoustic command. The Surface Communication Module sends the order through the water via a waterproof hydrophone; each SONABLOW device receives it and fires two underwater electric detonators in a pyrotechnic chain — one device or several, triggered from the surface on the operator's timing.
The firing line was always the weak link.
For decades, neutralising an underwater charge meant running an electric firing line back to the operator — a wire that snags, chafes, floods and ties the team to the charge until the moment of detonation. SONABLOW removes it entirely. The fire command travels as sound through the water, so the charge can sit ready and be fired the instant the area is clear — wherever the divers and the surface station happen to be.
From surface command to detonation
Place
EOD or combat divers rig the SONABLOW unit and its two detonators on the charge, then move clear of the blast radius.
Command
The Surface Communication Module connects to a waterproof hydrophone and sends an acoustic fire command through the water.
Receive
Each unit's acoustic receiver hears its command and draws on its own onboard energy source — no wire back to the surface.
Fire
The unit fires its two underwater electric detonators; one or many units can be triggered from the surface at any time.
The whole kill chain stays with the team
As part of RTsys's manned-and-unmanned MCM teaming, SONABLOW gives EOD and combat divers full autonomy across the complete cycle — identification, localisation, classification and neutralisation — without depending on a separate firing rig or a tethered link to the surface. Co-developed with French Navy divers and funded by the French Defence Innovation Agency (AID) through the RAPID programme, it was launched publicly at DSEI 2023 and is in the DGA qualification process.
The operator keeps permanent control of the firing command and can fire a single device or a whole pattern of charges, choosing the moment rather than racing a wire that is already in the water.
See the Surface Communication Module →SONABLOW specifications
Indicative configuration — final specification and safety arrangements confirmed at quotation.
- TypeUnderwater acoustic firing device
- Command methodEncrypted acoustic (replaces firing line)
- Surface controlSCM + waterproof hydrophone
- Comms range2 km, up to 5 km with PRB
- Max depth300 m
- Detonator outputs2 underwater electric detonators
- Firing modesSingle, clock, consecutive, countdown, simultaneous
- Simultaneous firingOne or several units, on command
- Device batteryUp to one week
- Surface module (SCM) batteryUp to 25 h
- Operated byEOD / combat divers
- Network roleMCM manned-unmanned teaming
- OriginRTsys — Caudan (Brittany), France
Divers clear. Charge ready. Fire when the area is safe.
Because the command is acoustic, the charge can be rigged and left armed while divers withdraw — then fired the moment the supervisor confirms the area is clear. No wire dictates the geometry of the neutralisation; the network does.
The rest of the MCM suite
Surface Communication Module
The hydrophone-linked surface station that sends SONABLOW its acoustic fire command.
Explore the SCM →
SONADIVE
The diver console used to classify the contact before the charge is placed and fired.
Explore SONADIVE →
AUV COMET-MCM
Finds the contacts in the first place and keeps the team located through neutralisation.
Explore the COMET-MCM →Part of a bigger mission
SepcoTech scopes and delivers this as one piece of a cross-supplier capability. See the missions it supports:
A safe pair of hands for defence at sea
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