Cruise missiles and ballistic missiles are used by many nations as offensive and defensive technology. How do cruise missiles and ballistic missiles maneuver, and what are the differences between the basic principles of these maneuvers?
Cruise Missile :
- Uses thrust for the whole trajectory
- Uses aerodynamic forces by moving control surfaces to move. May use thrust vectoring
- Uses thrust to reach very high altitude. After that, no thrust, only potential energy is used and converted to speed.
- Uses aerodynamic forces (for a limited extent) to move by deflecting control surfaces.
A cruise missile is rocket or jet powered and flies to its target within the atmosphere, using lift to stay up. Most have wings, although a few may use lifting body designs. They maneuver using control surfaces on the wings and tail like an airplane. Mission profiles can include big course changes, to evade air defenses, or to hug terrain to stay hidden. They can be launched from fixed ground positions but most are launched from mobile platforms. They tend to have shorter ranges than ballistic missiles.
A ballistic missile is a rocket that powers its way out of the atmosphere and coasts in an arc, re-entering the atmosphere before hitting its target. They have little maneuvering capability, once the boost phase is done it's all down to physics. Some warheads are able to maneuver a bit in re-entry in order to hit a pinpoint target, others are just rocks at that point. The largest ones are launched from fixed positions like missile silos but smaller ones are mobile.
Cruise missiles have rocket or jet engines that are powered during the entire flight. It allows the missile to cruise low through the atmosphere, sometimes just above ground level. Lift and guidance of the missile are achieved by aerodynamic forces.
Ballistic missiles on the other hand are not powered during most of their flight. During the launch they are given a high initial velocity and then coast throughout most of their flight. Their flight path is by approximation parabolic. Ballistic missiles are guided during brief periods of their flight, aerodynamically and/or by thrust vectoring. Intercontinental Ballistic missiles go into a suborbital paths and spend a considerable part of their trajectory outside the atmosphere.
A ballistic missile is one which flies in a ballistic trajectory. They usually are composed of a solid rocket booster stage lifting a warhead and guidance section aloft as a payload . After the booster burns out, the payload section continues on a ballistic trajectory to the target. Sometimes the booster motor is jettisoned after burnout.
Ballistic missiles vary in size and capability from battlefield types such as the ATACMS missile fired from the M270 MRLS, to regional range types such as the MGM-31 Pershing missile to intercontinental range types such as the Minuteman III. Warhead types can range from conventional aerial explosives like Tritonol 80/20 to chemical, nuclear or thermonuclear types. Some ballistic missile contain multiple and independently targeted warheads on a warhead bus.
Cruise missiles are essentially guided flying bombs - unmanned heavier than air aircraft capable of sustained, powered flight from launch until it reaches the target. They range in speed from subsonic to supersonic. Propulsion is generally provided by small gas turbine jet engines, though some of the newer, supersonic types are powered by solid fuel ramjet engines. Warheads carried are conventional, chemical or nuclear. Some of the best known cruise missiles are the AM39 Exocet anti-ship missile or the BGM-109 Tomahawk missile.
Difference between cruise and ballistic missiles
There are some important differences between cruise and ballistic missiles. These are:
- Ballistic missiles follow an arc-like trajectory and are launched from the land or sea
- They usually carry a nuclear warhead and are very heavy
- They rely on Earth’s gravity to fly down once launched
- They have much larger range
- Cruise missiles can also be launched from air and fly within Earth’s atmosphere
- They have their own engines and wings to strike the target
- They can be supersonic or sub-sonic and are highly accurate
- They usually carry conventional warheads although some cruise missiles can also be equipped with nuclear warheads
In both cases, these missiles are guided. That is, the flight path is pre-determined and very small alterations in flight are possible, if at all.