The VentureStar spaceplane, developed by Lockheed Martin in the 1990s, was a groundbreaking project aimed at creating a fully reusable launch vehicle. While its design utilized advanced technologies like the Linear Aerospike Engine and composite materials, much has changed since then in terms of technological advancements. In this article, we explore whether the VentureStar concept could be realized with today's technology and what modifications would be necessary to make it feasible.
Key Considerations
Engine Technology
One of the most critical components of the VentureStar spaceplane was its intended use of the Linear Aerospike Engine, which aimed to provide efficient performance across different phases of flight. However, current engine technologies, such as those used in SpaceX's Raptor or Blue Origin’s BE-4 engines, have seen significant advancements in efficiency and reliability. By leveraging these modern engines, the design could be optimized for performance and cost.
Materials
Advances in composite materials and manufacturing techniques, including 3D printing, have dramatically improved the ability to create lightweight yet robust components. This would allow for a more efficient and durable design, potentially reducing the overall weight and increasing the payload capacity of the spaceplane.
Avionics and Control Systems
Modern avionics systems are far more advanced and provide better navigation control and automation capabilities. This would enhance the safety and reliability of the spaceplane, making it a safer and more reliable means of transporting payloads into space.
Cost and Economics
The original VentureStar program was ultimately canceled due to high costs and technical challenges. Today's commercial spaceflight market is more mature, with companies like SpaceX and Blue Origin demonstrating that reusable launch systems can be economically viable. By leveraging existing successful models, the VentureStar could resurrect the concept with modern economics and cost-effectiveness.
Regulatory and Safety Standards
Current regulatory environments and safety standards would need to be considered. While these could add complexity, they would also ensure that the spaceplane meets stringent safety and performance requirements, ultimately enhancing its overall feasibility.
Practical Challenges and Solutions
Single-stage-to-orbit (SSTO) vehicles, such as the VentureStar, suffer from a significantly lower payload-to-weight ratio, typically 10:1. This means that for a large vehicle, the amount of payload transported is very limited. A two-stage-to-orbit (TSTO) approach, on the other hand, can significantly increase the amount of payload launched for the same size rocket, and the vehicles can be reused, as demonstrated by SpaceX and Blue Origin.
In the final iteration of the VentureStar, the design aimed to carry the payload in a cylinder on the back of the vehicle to free up more room for propellant. This concept can be adapted to create a practical design. By incorporating this design into a second-stage vehicle, it could be modified to resemble the Orbital Test Vehicle (OTV) currently operated by the U.S. Air Force for reusable space missions. This would give the VentureStar a new lease on life in the modern era.
To implement this, a blend of RP1 (rocket propellant 1) and hydrogen fuels could be used, with blending technology to transition from RP1 to hydrogen as the vehicle approaches orbit. This would dramatically reduce the size of the vehicle, which was previously enormous due to the low-density propellant requirements. Alternatively, it could use RP1 or methane alone as a first stage.
If the SSTO approach proves impractical, a second stage could still be launched off the back of the VentureStar. This second stage could be optimized for vacuum flight, either with a large engine bell or a conical aerospike. It would need to be at a safe distance from the VentureStar when igniting the aerospike.
The second stage could look like the OTV but larger and with a cleaner propellant to avoid contaminating the mothership, or it could resemble Dream Chaser for a closer fit to the VentureStar body.
Conclusion
In conclusion, while the VentureStar's concept could theoretically be realized using today's technology, practical challenges related to cost, regulatory approval, and market demand would play significant roles in determining its feasibility. Companies may opt to build on existing successful models rather than revisiting older concepts like VentureStar. However, with the right modifications and advancements in technology, the VentureStar could still have a place in modern space exploration.