Advances in High Speed Cruise Missiles
Technological Marvels are the Deadliest Anti-Ship Weapons
A cruise missile is basically a small, pilotless guided airplane that can carry an explosive warhead. Today, missiles can fly at least to the enormous 2.5 times the speed of sound (3,000 km/h or greater). The higher the speed, the less time a target ship has to detect the oncoming missile, and the less time to react to this threat.
Cruise Missile Types
Cruise missiles come in a number of variations and can be launched from submarines, destroyers or aircraft. Missiles may be designed for travel in different modes, either:
- Beneath the water level,
- At low altitudes just above the water, or
- At high altitudes, i.e. airborne.
Mode of travel affects missile speed . The above list is ordered according to increasing speed, with airborne missiles having the greatest speed. Additionally, an important aspect of missile performance is its range (how far it will travel), altitude height at which it can hit a target, and effectiveness of the guided system.
Mach Number
Missile speed is expressed in terms of Mach number, credited to the Austrian physicist and philosopher, Ernst Mach. It is a dimensionless number defined as the ratio of the speed of an object moving through a fluid (such as the air), divided by the speed of sound:
Mach: Mach = v/v0,
where v is the speed of the object, v0 is the speed of sound. Based on a standard atmospheric model, v0 has been defined to be 1,225 km/h or 761.2 mph. For example, an object travelling at twice the speed of sound has a Mach number of 2.0. Flight can be roughly classified according to four categories depending on a Mach number range:
- Subsonic, Mach < 1
- Transonic, .8 < Mach < 1.2
- Supersonic, 1.2 < Mach < 5
- Hypersonic, Mach > 5
Sonic speed refers to the speed of sound itself, which has a Mach of 1.0.
Deadliest Missile Programs
Missilethreat.com provides a list of 14 nations currently developing cruise missiles, and details known missile characteristics. Wikipedia has comprehensive information according to categories of missile programs. Examples are ranked by speed, which may correlate with relative age of their technology.
- The first hypersonic missile expected to be ready by 2012-3 is the Russian BrahMos 2 with the incredible Mach 8.0. It is jointly developed by Russia and India.
- A number of supersonic range missiles are already operational, notably from Russia and China. The Russian "Sunburn" missile is among the better known due to its Mach 2.5, nuclear warhead carrying capacity, and exported to other countries such as China and Iran. The US has its RATTLRS system (Mach 4) currently under development.
- Next, in the subsonic range, are a variety of missiles developed by different countries including the United States.
Sunburn Missile
The Russian supersonic SS-N-22 Moskit cruise missile, NATO code-named "Sunburn", has been called “the most lethal anti-ship missile in the world”, and has the following features:
- Mach is 2.5 , it thus travels at 3,000 km/h
- Can be armed with a 200 kiloton nuclear warhead
- Flies barely 2m above the water level
- Has a range of 120 km but can be 250 km if air-launched
- The Sunburn has never yet been used in a war theatre
Conclusion
The effectiveness of cruise missiles depends on speed, range and accuracy of the guided system. Today, missile technology has advanced to produce cruise missiles with Mach numbers within the supersonic range (3,000 km/h or greater) but new developments are testing missiles in the awesome hypersonic range.
