The Expendable Launch Vehicle (ELV) program is a cornerstone of NASA's mission to explore and utilize space. ELVs are designed for single-use, delivering payloads such as satellites, scientific instruments, and interplanetary probes into various orbits or trajectories. This article provides an overview of the ELV program, its significance, and its status as of May 27, 2011.

Overview of Expendable Launch Vehicles

Expendable Launch Vehicles are rockets engineered for one-time use, as opposed to reusable vehicles like the Space Shuttle. They are categorized based on payload capacity and mission requirements. The primary ELVs utilized by NASA include:

  • Atlas V: Manufactured by Lockheed Martin and United Launch Alliance (ULA), the Atlas V is known for its reliability and versatility, capable of launching a wide range of payloads.
  • Delta II: Also produced by ULA, the Delta II has been a workhorse for NASA, successfully deploying numerous satellites and scientific instruments.
  • Delta IV: A more powerful variant, the Delta IV is designed for heavier payloads and more demanding missions.
  • Falcon 1 and Falcon 9: Developed by SpaceX, these vehicles represent a new generation of commercial ELVs, with Falcon 9 being particularly notable for its reusability features.

ELV Program Status as of May 27, 2011

As of May 27, 2011, NASA's ELV program was actively engaged in several key missions, reflecting the agency's commitment to advancing space exploration and scientific research. Notable activities included:

  • Glory Mission: Scheduled for launch on February 23, 2011, the Glory spacecraft aimed to study the Earth's climate by measuring solar energy and atmospheric particles. Prelaunch processing at Vandenberg Air Force Base was progressing, with the spacecraft mated to the payload cone in preparation for encapsulation into the payload fairing. The Taurus XL 3110 launch vehicle was also being prepared for the mission.
  • Interstellar Boundary Explorer (IBEX): The IBEX mission, utilizing the Pegasus XL launch vehicle, was in the final stages of preparation. The spacecraft was undergoing testing of its science instruments, with fueling and spin balancing scheduled. The launch was planned for October 5, 2008, at the Reagan Test Site in the Pacific Atoll. This mission aimed to study the boundary between the solar system and interstellar space.

Challenges and Considerations

During this period, NASA faced several challenges concerning the ELV program:

  • Cost and Availability: There were concerns about the availability, reliability, and increased costs associated with ELVs. The Delta II, a reliable option for mid-sized payloads, was nearing the end of its operational life, leading to potential gaps in available launch vehicles. This situation necessitated a reliance on more expensive evolved ELVs like Delta IV and Atlas V, which were designed for larger payloads than many of NASA's missions required. Additionally, the emergence of new commercial launch vehicles presented both opportunities and uncertainties regarding their reliability and cost-effectiveness.

Future Outlook

Looking ahead, NASA's ELV program was poised to evolve in response to these challenges. The agency was actively exploring partnerships with commercial launch providers to enhance the availability and affordability of launch services. The development of new, more cost-effective ELVs was a priority, aiming to ensure that NASA could continue to meet its mission objectives without compromising on reliability or safety.

In summary, as of May 27, 2011, NASA's Expendable Launch Vehicle program was integral to the agency's space exploration efforts. Despite facing challenges related to cost and vehicle availability, the program's ongoing missions and strategic planning underscored NASA's commitment to advancing our understanding of space through reliable and efficient launch capabilities.

Sources

  • NASA — Expendable Launch Vehicle Status Report 27 January 2011 —
  • NASA — Expendable Launch Vehicle Status Report 22 —
  • NASA — Expendable Launch Vehicle Status Report 18 —
  • NASA — Expendable Launch Vehicle Status Report 24 —
  • NASA — Expendable Launch Vehicle Status Report 21 —