Typically, a warhead is the explosive material and detonator that is delivered by a missile, rocket, or torpedo.
During the early development of naval torpedoes, they could be equipped with an inert payload that was intended for use during training, test firing and exercises. This was referred to as a peacehead. The explosive payload carried by weapons intended for use in combat became known as a warhead. The term peacehead subsequently fell out of use.
Types of warheads include:
- Explosive: An explosive charge is used to disintegrate the target, and damage surrounding areas with a shock wave.
- Conventional: Chemicals such as gunpowder and high explosives store significant energy within their molecular bonds. This energy can be released quickly by a trigger, such as an electric spark. Thermobaric weapons are something of a special case.
- Blast: A strong shock wave is provided by the detonation of the explosive
- Fragmentation: Metal fragments are projected at high velocity to cause damage or injury.
- Continuous rod: Metal bars connected on their ends forming a continuous narrow zig-zag ring after ignition - able to cut aerial structures.
- Shaped charge or explosively formed penetrator: The effect of the explosive charge is focused onto a specially shaped metal liner to project a hypervelocity jet of metal, to perforate heavy armour.
- Nuclear: A runaway nuclear fission or nuclear fusion reaction causes immense energy release.
- Chemical: A toxic chemical, such as poison gas or nerve gas, is dispersed, which is designed to injure or kill human beings.
- Biological: An infectious agent, such as anthrax spores, is dispersed, which is designed to sicken or kill humans.
- Kinetic: Collides the target with high speed. Detonation is not applicable.
Often, a biological or chemical warhead will use an explosive charge for rapid dispersal.
The types of detonators are:
- Contact: When the warhead makes physical contact with the target, the explosive is detonated. Sometimes combined with a delay, to detonate a specific amount of time after contact.
- Proximity: Using radar, sound waves, a magnetic sensor, or a laser the warhead is detonated when the target is within a specified distance. It is often coupled with directional explosion control system that ensures that the explosion sends the shrapnel primarily towards the target that triggered it.
- Remote: remotely detonated via signal from operator (Not normally used for warheads except for self-destruction)
- Timed: Warhead is detonated after a specific amount of time.
- Altitude: Warhead is detonated once it falls to a specified altitude. See air burst.
- Combined: Any combination of the above.