SpaceFields Reaches Milestone with Successful AeroSpike Engine Hot Test

In a significant advancement for India's aerospace sector, Bengaluru-based startup SpaceFields Pvt. Ltd., incubated at the Indian Institute of Science (IISc), has successfully conducted a hot-fire test of the nation's first aerospike rocket engine. This milestone was achieved at the IISc Propulsion Test Facility in Challakere, Chitradurga district.

Technical Specifications and Test Outcomes

The aerospike engine, measuring 168 mm, was ignited during a static test. Upon ignition, the engine exhibited initial chuffing but quickly transitioned to stable combustion. The test utilized a high-performance Hydroxyl-terminated polybutadiene (HTPB)-based composite propellant. Key performance metrics recorded during the test include:

• Maximum Pressure: 11 bar
• Peak Thrust: 2000 Newtons
• Total Impulse: 54,485.9 Newton-seconds

These results underscore the engine's robust performance and its potential applicability in various aerospace missions.

Innovative Design and Materials

SpaceFields selected Titanium Grade 5 (Ti-6Al-4V) as the primary material for the engine's construction, owing to its superior strength-to-weight ratio compared to traditional materials like Inconel or steel. This choice facilitates significant weight reduction while maintaining the structural integrity necessary to withstand the extreme pressures and thrust generated during operation.

A notable innovation in the engine's design is the implementation of a patent-pending Glass Fibre Reinforced Polymer (GFRP)-based ablative thermal insulation. This composite liner undergoes pyrolysis above 1400K and has been tested to withstand temperatures up to 3000K, effectively protecting the aerospike's surface from high-temperature exhaust gases.

Advantages of Aerospike Technology

Aerospike engines offer a unique advantage over traditional bell-nozzle engines through altitude compensation. This design allows the engine to adjust to varying atmospheric pressures, maintaining optimal efficiency across different altitudes. Consequently, aerospike engines can potentially reduce the need for multiple stages and decrease fuel consumption in orbital missions. SpaceFields is also exploring the integration of thrust vectoring into the aerospike engine to further enhance its capabilities.

Implications for India's Space Technology

This successful test marks a significant milestone in India's space technology development, positioning SpaceFields as a leader in next-generation rocket propulsion systems. The company's efforts are supported by funding from the Startup India Seed Fund, Boeing India, and grants from the governments of Karnataka and Odisha. In February 2024, SpaceFields raised $800,000 (Rs 6.5 crore) to further the development and testing of critical hardware and various subsystems, research and development in energetic materials, and to expand the company's team.

As SpaceFields continues to innovate, this achievement could lead to more efficient and cost-effective space launch systems, bolstering India's position in the global space industry.