Delta-IV
The Delta-IV is a family of expendable launch vehicles developed by the United Launch Alliance (ULA), a joint venture between Boeing and Lockheed Martin. Here are key details regarding the Delta-IV:
History
The Delta-IV rocket was conceived as part of the EELV (Evolved Expendable Launch Vehicle) program, which was initiated by the United States Air Force in the late 1990s to develop a new generation of launch vehicles to replace older systems like the Delta II and Atlas II. The first Delta-IV launch occurred on November 20, 2002, from Cape Canaveral.
Design and Configurations
The Delta-IV comes in several configurations:
- Delta IV Medium: This configuration uses a common booster core (CBC) with up to four solid rocket boosters (SRBs) for added thrust. It can launch payloads to various orbits.
- Delta IV Medium+: Similar to the Medium but with an extended payload fairing and/or more SRBs, enhancing its payload capacity.
- Delta IV Heavy: This variant uses three CBCs strapped together, making it the most powerful of the Delta-IV family. It's designed for heavy payloads, especially for national security missions.
Performance
- Delta IV Medium: Can place approximately 4,200 kg to Geostationary Transfer Orbit (GTO).
- Delta IV Heavy: Can lift up to 28,790 kg to Low Earth Orbit (LEO) or approximately 14,220 kg to GTO.
Notable Missions
- Orion EFT-1 - The first test flight of NASA's Orion spacecraft in 2014, launched by a Delta IV Heavy.
- GPS IIF - Several satellites in the GPS Block IIF series were launched on Delta-IV vehicles.
- NROL-26 - A National Reconnaissance Office mission launched by Delta IV Heavy in 2012.
Current Status
As of the latest information, Delta-IV launches are becoming less frequent as ULA transitions to the Vulcan Centaur rocket, which is intended to replace both the Delta-IV and Atlas V families. However, some Delta-IV Heavy launches are still scheduled for critical national security payloads.
External Links
Related Topics