Abstract: A flare including: a casing; and a grain assembly, at least a portion of the grain assembly being slidably disposed in the casing, the grain assembly including: a shell structure; and a grain component at least partially disposed in the shell structure, the grain component including at least one combustible material and at least one reactive material positioned relative to the combustible material and configured to ignite combustion of the at least one combustible material; wherein the shell structure includes one or more fins at an aft end of the shell structure, the one or more fins being restrained into a first shape in the casing and configured to have a second shape, different from the first shape, when the restraint is removed.