The Indian Space Research Organisation (ISRO) has successfully carried out a demonstration of restarting its Vikas liquid engine at a test facility at Propulsion Complex in Mahendragiri. The space agency said the Vikas engine is the workhorse that powers the liquid stages of its launch vehicles. This test on January 17 marks a milestone in the development of technologies for recovery of stages, leading to reusability in future launch vehicles.
Key Details of the Test:
- Duration and Phases:
- The Vikas engine was initially fired for 60 seconds.
- It was then shut off for a cooling period of 120 seconds.
- Subsequently, the engine was restarted and fired for an additional 7 seconds.
- Performance:
- All engine parameters were nominal, aligning with expected outcomes.
- This capability is essential for missions requiring controlled, staged engine firings.
About the Vikas Engine:
- The Vikas engine is the backbone of ISRO’s liquid propulsion systems, powering the liquid stages of its launch vehicles.
- Operates on storable propellants using a pump-fed gas generator cycle.
- The human-rated version of the Vikas engine boasts:
- Enhanced structural integrity.
- Improved assembly processes.
- Advanced health monitoring for greater reliability in crewed missions.
- The twin Vikas engines are central to the LVM3 launch vehicle (formerly GSLV Mk III), ISRO’s heavy-lift rocket. Notably, in April 2023, the clustered configuration of two L110-G Vikas engines was used in the air-lit liquid core stage of a human-rated launch vehicle (LVM3-G).
Comparison of Liquid & Solid Rocket Engines:
- Liquid Rocket Engines:
- Advantages:
- Thrust can be throttled or stopped entirely, allowing for precise control.
- Engines can be restarted after shutdown.
- Disadvantages:
- Complex systems with pumps, pipes, and storage tanks increase mass and complexity.
- Propellants (e.g., liquid hydrogen and liquid oxygen) must be loaded just before launch.
- Common Usage:
- Preferred for stages requiring fine control or restart capabilities. Often use kerosene and liquid oxygen for efficiency in dense atmospheric regions.
- Advantages:
- Solid Rocket Engines:
- Advantages:
- Simple design with propellants pre-mixed into a solid form.
- Can be stored for years, making them reliable and low-maintenance.
- Disadvantages:
- Cannot throttle or stop thrust once ignited.
- Requires destructive measures to halt combustion.
- Common Usage:
- Often used for boosters or missions with less critical control requirements.
- Advantages:
(Sources: ISRO, NASA and ESA)
