OVERVIEW: SEALEM is a naval RF (radio-frequency) chaff decoy developed by Lacroix as part of the SEACLAD family. It is designed to seduce radar-guided missiles by creating off-board false radar targets using passive corner reflector elements.

DETAILS: SEALEM is launched from Lacroix's SYLENA series of fixed-angle soft-kill decoy launchers, including SYLENA LW, Mk1, and Mk2. It releases radar-reflective submunitions with broadband response across I-, J-, and Ka-bands to defeat both legacy and modern radar seekers. The corner reflector payload is designed to mimic the radar cross-section of a ship, with optimized polarization and dispersion for enhanced deception. SEALEM can be deployed in salvos or in coordination with other SEACLAD decoys like SEALIR or SEALAT, as part of a layered soft-kill defense system.

FONCTION:
Threat detected by onboard ESM or radar warning receiver.
Launcher fires SEALEM round in pre-set trajectory.
Decoy releases radar-reflective payload forming a false radar signature to lure or break missile lock.

SOURCE:
Naval News – Sylena decoy system overview ; EDR Magazine – SEALEM and SEACLAD payloads ; Mer et Marine – Sylena Mk2 operational use ; https://www.lacroix-defense.com/en/naval-forces/soft-kill