Abstract: A nonelectronic device tracks and homes in on a target to be destroyed by a projectile having a body in which the device is carried. An optical lens disposed in a nose cone of the projectile body receives and focuses infrared radiation or heat from the target, which is an electromagnetic field that may be emanating from an exhaust plume of an incoming enemy intercontinental ballistic missile. A detector converts the radiation focused by the lens into thermal energy. A Golay-type cell receives the thermal energy and converts it into a fluid signal that is transferred via a nonelectronic coupler to a fluidic circuit. A fluidic rate gyro seeks the target and guides the projectile towards the target to be destroyed. A key advantage of the invention is that the nonelectronic infrared heat tracking device is comprised of inert mechanical elements and fluids. Therefore, the device is unaffected by intense magnetic and electromagnetic fields, except for those fields within the design band of the detector element.