OVERVIEW: The Mk 216 Sea Gnat is a 112 mm distraction chaff round used in NATO naval decoy systems. It is designed to divert radar-guided threats away from the vessel by deploying radar-reflective material at range.

DETAILS: The Mk 216 was introduced in 1988 as the long-range distraction variant of the Sea Gnat decoy family. It is compatible with 112 mm launchers such as the Mk 36 SRBOC and the Royal Navy’s Outfit DLB system. Once launched, the round travels to a standoff distance before deploying a cloud of aluminum-coated dipoles to generate radar clutter in a location separate from the ship. It is used by the U.S. Navy and Royal Navy as part of their layered soft-kill defense systems.

FONCTION:
Launched from 112 mm SRBOC or equivalent naval decoy launchers.
Propelled to a standoff range before releasing chaff payload.
Produces a radar-reflective cloud to draw missiles away from the ship.

SOURCE:
Wikipedia (https://en.wikipedia.org/wiki/Sea_Gnat) ; U.S. Navy Passive Decoys Flipbook (Indiana University) ; Navy Lookout – “Royal Navy upgrades its passive decoy launchers” (https://www.navylookout.com/royal-navy-upgrades-its-passive-decoy-launchers/) ; Free Library – “Advances in Passive Expendable Countermeasures” (https://www.thefreelibrary.com/Advances+in+passive+expendable+countermeasures.-a014348027)