Recently, North Korea test-fired a intercontinental ballistic missile (ICBM) powered by solid fuel.
About Solid-fuel missiles
- They do not need to be fuelled immediately ahead of launch. These are often easier and safer to operate.
- They require less logistical support, making them harder to detect and more survivable than liquid-fuel weapons.
- Solid propellants are a mixture of fuel and oxidiser. Metallic powders such as aluminium often serve as the fuel, and ammonium perchlorate is the most common oxidiser.
- The fuel and oxidiser are bound together by a hard rubbery material and packed into a metal casing. When solid propellant burns, oxygen from the ammonium perchlorate combines with aluminium to generate enormous amounts of energy and temperatures of more than 5,000 degrees Fahrenheit, creating thrust and lifting the missile from the launch pad.
Liquid propellants
- Liquid propellants provide greater propulsive thrust and power, but require more complex technology and extra weight.
- Solid fuel is dense and burns quite quickly, generating thrust over a short time.
- Solid fuel can remain in storage for an extended period without degrading or breaking down – a common issue with liquid fuel.
