The Pentagon is steadily increasing the use of various drones across several branches of the military.
Indeed, certain models can now be produced cheaply enough for them to be remotely piloted into enemy targets, rather than being loaded with more expensive ordnance.
These so-called Kamikaze vehicles currently include unmanned aircraft, ground robots, and naval vessels specifically designed to destroy themselves as they collide with a target.
As noted above, it makes sense for cheaper unmanned vehicles to crash into an enemy target, rather than to engage the target with a missile, bomb or mine. To be sure, using direct impact to destroy a target is more cost effective, simply because the craft or vehicle it doesn't require multiple operators and can be accomplished with manned or automated navigation techniques.
One such aircraft is the AeroVironment Switchblade or kamikaze drone which essentially functions as an autnomous grenade with extended range. The aircraft - which is fired from a 60 cm mortar-like launch tube - weighs some 2.5 kg and is designed to be carried in a soldier's backpack. Once the drone clears the launch tube it deploys four wings and activates a nose mounted camera for navigation, intelligence and surveillance activities in real-time.
The aircraft is capable of flying to a specific set of GPS coordinates at speeds of up to 85 knots. Once the operator identifies the target, a command can be sent to the Switchblade ordering it to dive towards and destroy a painted target.
The US Navy also fields its own autonomous vehicles, including the SeaFox unmanned submersible which measures 1.3 m long and weighs in at 43 kg. The vessel is guided by fiber optics to depths of up to 300 m and can travel at up to 6 knots on missions of up to 100 minutes in duration.
Once the unmanned underwater vehicle is close to the target, it verifies identity using an onboard camera. The SeaFox then detonates a large caliber shaped charge at close range to a mine or rams it directly.