About Scramjet Engine:
- A Scramjet (Supersonic Combustion Ramjet) is an air-breathing engine designed to operate efficiently at hypersonic speeds (Mach 5 and above).
- It does not use rotating compressors, relying instead on the vehicle’s high speed to compress air.
- Scramjets enable supersonic combustion, making them suitable for Hypersonic Cruise Missiles (HCMs).
- It carries liquid Hydrogen as fuel and liquid Oxygen for combustion (oxidiser) to generate thrust.
- The fuel efficiency of the scramjets tends to be significantly better than that of traditional turbojets and ramjets.
- India is the fourth country to demonstrate the flight testing of a Scramjet Engine.
- Scramjet Engine Working Principle:
- Air intake: Vehicle must already be flying at supersonic speeds (Mach 3+).
- Compression: High-speed movement compresses the incoming air.
- Combustion: Hydrogen fuel is injected and ignited while air remains supersonic.
- Thrust Generation: Expanding gases create thrust (based on Newton’s Third Law).
- Scramjets need rocket-assisted takeoff as they can’t generate thrust at zero speed.
What are Hypersonic Missiles?
- It refers to one which travels faster than Mach 5, or five times the speed of sound.
- There are two types:
- Hypersonic Glide vehicles (HGV): These are launched from a rocket, similar to regular ballistic missiles, before gliding to a target.
- Hypersonic Cruise Missiles: They are powered throughout their flight via air-breathing engines called Scramjets, after acquiring their target.
