ULA phased out the baseline RS-68 engine with the launch of Delta flight 371 on 25 March 2015. Lift capacity was increased by developing the higher-performance RS-68A engine, which first flew on 29 June 2012. A single National Reconnaissance Office (NRO) payload required an increase in the lift capability of the Delta IV Heavy. The possibility of a higher performance Delta IV was first proposed in a 2006 RAND Corporation study of national security launch requirements out to 2020. In 2015, ULA stated that a Delta IV Heavy is sold for nearly US$400 million. With the exception of the first launch, which carried the Eutelsat W5 commercial communications satellite, all Delta IV launches have been paid for by the US government. In March 2015, ULA announced plans to phase out the Delta IV Medium by 2018. Chung passed on classified information on designs including the Delta IV rocket to China and was sentenced to 15 years. In February 2010, naturalized citizen Dongfan Chung, an engineer working with Boeing, was the first person convicted under the Economic Espionage Act of 1996. In addition a US$557.1 million option was added to cover FY10. On 8 August 2008, the USAF Space and Missile Systems Center increased the "cost plus award fee" contract with BLS for US$1.656 billion to extend the period of performance through the 30 September 2008 ( FY09). Īs of 2009, the USAF funded Delta IV EELV engineering, integration, and infrastructure work through contracts with Boeing Launch Services (BLS). In 2005, Boeing stated that it sought to return the Delta IV to commercial service. In 2003, Boeing pulled the Delta IV from the commercial market, citing low demand and high costs. Furthermore, as an unproven design it had difficulty finding a market in commercial launches, and Delta IV launch costs are higher than comparable vehicles of the same era. However, the Delta IV entered the space launch market when global capacity was already much higher than demand. īoeing initially intended to market Delta IV commercial launch services. The RIFCA featured six ring laser gyroscopes and accelerometers each, to provide a higher degree of reliability. The 元 Technologies Redundant Inertial Flight Control Assembly (RIFCA) guidance system originally used on the Delta IV was common to that carried on the Delta II, although the software was different because of the differences between the Delta II and Delta IV. In 2002, the Delta IV was first launched, with the RS-68 becoming the first large liquid-propellant rocket engine designed in the United States since the Space Shuttle main engine (SSME) in the 1970s. This would have featured the Delta II second stage, an optional Thiokol Star 48B third stage, and the Delta II payload fairing, all atop a single Common Booster Core (CBC). ĭuring the Delta IV's development, a small variant was considered. Perhaps the most significant change was the switch from kerosene to liquid hydrogen fuel, with new tankage and a new engine required. While the Delta IV retains the name of the Delta family of rockets, major changes were incorporated. The latest evolutionary development of the Delta rocket family, Delta IV was introduced to meet the requirements of the United States Air Force's (USAF) Evolved Expendable Launch Vehicle (EELV, now National Security Space Launch (NSSL)) program. Final assembly was completed at the launch site by ULA: at the horizontal integration facility for launches from SLC-37B pad at Cape Canaveral and in a similar facility for launches from SLC-6 pad at Vandenberg Air Force Base. Payloads that would have previously fly on Medium and Heavy are moving to either the existing Atlas V or the forthcoming Vulcan.ĭelta IV vehicles were built in the ULA facility in Decatur, Alabama. As of 2023, the Heavy has flown its penultimate mission, NROL-68. The Delta IV originally had two main versions which allowed the family to cover a range of payload sizes and masses: the retired Medium (which had four configurations) and Heavy. The Delta IV was primarily a launch vehicle for United States Air Force (USAF) military payloads, but was also used to launch a number of United States government non-military payloads and a single commercial satellite. Originally designed by Boeing's Defense, Space and Security division for the Evolved Expendable Launch Vehicle (EELV) program, the Delta IV became a United Launch Alliance (ULA) product in 2006. Second stage – Delta Cryogenic Second Stage (DCSS)ĭelta IV was a group of five expendable launch systems in the Delta rocket family introduced in the early 2000s. Boosters (Heavy) – Common Booster Core (CBC)Ģ45 seconds (328 seconds in Heavy configuration)
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |