The AGM 114 Hellfire missile was developed in the mid-80’s as an air to surface missile for use in anti-terrorism. It acquired the name Hellfire as it was originally titled Helicopter Launched, Fire and Forget Missile. It can be launched off a number of platforms including air, sea and ground. Its development originated in 1974 as a weapon to take out tanks and other fighting vehicles but it was not manufactured until 1982 and testing began 2 years later.
Essentially, each missile has its own guiding system which comes complete with steering and propulsion control. It is highly explosive and has a warhead that houses enough power to easily take apart the heaviest military armour.
The missiles are carried by Apache helicopters with 2 pillars attached to each of its wings and every one can carry four of the missiles allowing the helicopter to carry up to 16 missiles. Each one will receive activation instructions from a computer which transmits the signal to the missile and activates its propellant. This will create 500 lbs of force which will break the missile free from its rail. It then accelerates and that will trigger the deployment mechanism and when it hits the target, the warhead detonates.
The system in place in the missile will direct it to its target and easily hit the mark. This is done in conjunction with the helicopter to which the missile is attached where a laser will mark out the target and that pulse from the laser will trigger a coding pattern that the missile with interpret. Prior to receiving the firing signal, the computer and the missile communicate with each other and to tell it what to expect in terms of the pattern of the pulse. The laser seeker on the missile then searches for the light from the laser and will follow it. The guidance system will then make the necessary calculations that determine what steering is required to accurately hit the target. Should the missile need to change course, its flight fins will shift to alter the direction. This is fundamentally the same way that a plane steers itself.
The guidance system employed in the Hellfire is extremely effective but there are a few limitations. Weather systems can act as obstacles blocking the beam so that it doesn’t reach the target. The same (or different weather systems) can block the view of the missile itself if it passes through a cloud. The helicopter must remain completely stable in order to maintain contact with the target and it also needs to be in the open and that will leave it vulnerable.
There is a second iteration of the Hellfire – the Hellfire II – with is also used in Apache Longbow helicopters and this version addresses those issues. The missile houses radar seeking technology as opposed to laser. The radar will locate the target and then the missile will read that feed and aim at it. The radar waves are heard and not seen and thus clouds cannot obscure them so the missile will not misread the signals. The helicopter as such can remain covered once it has established once it makes initial contact with the target.