Silicone-fiber-cork ablative insulation material and method of spraying the insulation material

An insulation material suitable for use on rocket motor cases and airframe surfaces is provided. The insulation material is formed from a mixture of cork particulate, a plurality of fibers, and a siloxane based binder. The cork particulate, the binder, and the fibers are present in a mass ratio of 10-100 parts binder to 0.1-50 parts fiber to 1-100 parts cork. The insulation material may have a homogeneous or non-homogeneous composition and may be composite in nature.