The ARM-18A "Guardian-I" is an prototype model of the "ARM-18 "Guardian" series that still in development and trials, the ARM-18 Guardian-I missile is designed and developed in Tactical-Ordnance Survey Station (TOSS) and tested above the Bay of Wright Isles. This guided missile model is designated as a ARM-18A "Guardian-I", and the ARM is stands for Aerial Restrain-Missile. The ARM-18A Guardian-I is an "infrared heat-seeking" guided missile (also called as a "heat-homing rocket"), that track the infrared heat produced by the aircraft propulsion, this missile accuration is depending on the intensity of the infrared heat-radiation from the target, generally the jet engines produces more infrared heat-radiation than the other conventional aircraft-engine, more infrared heat-radiation giving more contrast to the image that achieved by the infrared heat-seeker so the target will be more visible and it allows the missile to track the target more accurately, the infrared heat-seeker of the ARM-18A Guardian-I will guide the missile with the "proportional-pursuit system", this is a system that calculate the impact point of the missile towards the target and the missile will be guided to the flight path towards the estimated point of impact of the target that has been calculated by the missile guidance system, the infrared heat-seeker of the ARM-18A Guardian-I itself have a maximum off-boresight angle of 5 degrees, and the maximum range of 2.1 nmi (2.5 mi/4 km), and the minimum range of 5 nmi (0.6 mi/1 km). The ARM-18A Guardian-I is employs a high-explosive (HE) fragmentation warhead that has a weight of 22 lbs (10 kg), and this missile has a infrared proximity fuze detonation mechanism, this detonation mechanism will be detonate the warhead of the missile in the estimated missile to target range of 33 ft (10 m) to 29 ft (9 m) from the target, the successful detonation rate probability is 48% to 52%. The ARM-18A Guardian-I is propelled by solid-fuel rocket, that burn in 2 seconds, that able accelerate the missile to the velocity of mach 2.0 (1534 mph/2470 kmh), in this speed the missile are able to accelerate up to 15 Gravitational-Force of acceleration. The high-speed manueverbility performance of ARM-18A Guardian-I is provided by its control-surfaces that has a chord of 3.6 in (91.4 mm) with this chord length, the control surfaces can be easier to moved by the control surface servo, and the control surface itself has a maximum deflecting angle of 10 degrees. The ARM-18A Guardian-I missile is has a total weight of 218 lbs (99 kg), has a length of 8.5 ft (2.6 m), has a diameter of 6 in (152 mm), and it has a wingspan of 16 in (396 mm).