EELV
Encyclopedia
Expendable launch system
An expendable launch system is a launch system that uses an expendable launch vehicle to carry a payload into space. The vehicles used in expendable launch systems are designed to be used only once , and their components are not recovered for re-use after launch...
program of the United States Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
(USAF), intended to assure access to space for Department of Defense
United States Department of Defense
The United States Department of Defense is the U.S...
and other United States government
Federal government of the United States
The federal government of the United States is the national government of the constitutional republic of fifty states that is the United States of America. The federal government comprises three distinct branches of government: a legislative, an executive and a judiciary. These branches and...
payloads. The program, which began in the 1990s with the goal of making government space launches more affordable and reliable, resulted in the development of two launch systems, Delta IV and Atlas V
Atlas V
Atlas V is an active expendable launch system in the Atlas rocket family. Atlas V was formerly operated by Lockheed Martin, and is now operated by the Lockheed Martin-Boeing joint venture United Launch Alliance...
. These two launch systems are the primary methods for launching U.S. military satellite
Military satellite
A military satellite is an artificial satellite used for a military purpose, often for gathering intelligence, as a communications satellite used for military purposes, or as a military weapon.-Description:*Star Wars program...
s.
Development
The U.S. Air ForceUnited States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
assembled its initial blue print for the EELV in 1994, following many years of government funded studies into an improved system and architecture, which was intended to replace most if not all existing “legacy” spacelifters (e.g. Delta II
Delta II
Delta II was an American space launch system, originally designed and built by McDonnell Douglas. Delta II is part of the Delta rocket family and was in service from 1989 until November 1, 2011...
, Atlas II
Atlas II
Atlas II was a member of the Atlas family of launch vehicles, which evolved from the successful Atlas missile program of the 1950s. Atlas II was the last Atlas to use a three engine, "stage-and-a-half" design: two of its three engines were jettisoned during ascent, but its fuel tanks and other...
/Centaur
Centaur (rocket stage)
Centaur is a rocket stage designed for use as the upper stage of space launch vehicles. Centaur boosts its satellite payload to geosynchronous orbit or, in the case of an interplanetary space probe, to or near to escape velocity...
, Titan IV
Titan IV
The Titan IV family of space boosters were used by the U.S. Air Force. They were launched from Cape Canaveral Air Force Station, Florida, and Vandenberg Air Force Base, California. At the time of its introduction, the Titan IV was the "largest unmanned space booster used by the Air Force."The...
, etc.). The architecture called for the spacelifter to be based on standardized fairings, liquid core vehicles, upper stages, and solid rocket
Solid rocket
A solid rocket or a solid-fuel rocket is a rocket engine that uses solid propellants . The earliest rockets were solid-fuel rockets powered by gunpowder; they were used by the Chinese in warfare as early as the 13th century and later by the Mongols, Arabs, and Indians.All rockets used some form of...
s. The standard payload interface was also proposed as another way to save money and improve efficiency.
The initial bids came from four major defense contractors: Lockheed Martin
Lockheed Martin
Lockheed Martin is an American global aerospace, defense, security, and advanced technology company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It is headquartered in Bethesda, Maryland, in the Washington Metropolitan Area....
, Boeing
Boeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...
, McDonnell Douglas
McDonnell Douglas
McDonnell Douglas was a major American aerospace manufacturer and defense contractor, producing a number of famous commercial and military aircraft. It formed from a merger of McDonnell Aircraft and Douglas Aircraft in 1967. McDonnell Douglas was based at Lambert-St. Louis International Airport...
, and Alliant Techsystems
Alliant Techsystems
Alliant Techsystems Inc., most commonly known by its ticker symbol, ', is one of the largest aerospace and defense companies in the United States with more than 18,000 employees in 22 states, Puerto Rico and internationally, and 2010 revenues in excess of an estimated...
. Each of the bids had a variety of different concepts. One of the contractors, Boeing, initially proposed utilizing the Space Shuttle Main Engine
Space Shuttle main engine
The RS-25, otherwise known as the Space Shuttle Main Engine , is a reusable liquid-fuel rocket engine built by Pratt & Whitney Rocketdyne for the Space Shuttle, running on liquid hydrogen and oxygen. Each Space Shuttle was propelled by three SSMEs mated to one powerhead...
s (SSME). McDonnell Douglas merged with Boeing in 1997 and used its Delta IV spacelifter for their EELV proposal.
Design
Boeing and Lockheed Martin were both collectively awarded US$ 100 million for the final phase of the bid. Both companies built their designs around modularization, standardization and minimizing the amount of equipment and using proven, reliable and simplified systems. Boeing developed the Common Booster CoreCommon Booster Core
The Common Booster Core is an American rocket stage, which is used on the Delta IV rocket as part of a modular rocket system. Delta IV rockets flying in the Medium and Medium+ configurations each use a single Common Booster Core as their first stage, whilst the Heavy configuration uses three; one...
(CBC) that would be the center of the Delta IV. For the Atlas V
Atlas V
Atlas V is an active expendable launch system in the Atlas rocket family. Atlas V was formerly operated by Lockheed Martin, and is now operated by the Lockheed Martin-Boeing joint venture United Launch Alliance...
Lockheed Martin did something similar, calling it a Common Core Booster
Common Core Booster
A modular rocket is a type of multistage rocket which features components that can be interchanged for specific mission requirements. Several such rockets use similar concepts such as unified modules to minimize expenses on manufacturing, transportation and for optimization of support...
(CCB).
Industrial espionage
Boeing was found to be in possession of proprietary documents from Lockheed Martin. To end litigation, both companies agreed to join forces and formed the United Launch AllianceUnited Launch Alliance
United Launch Alliance is a joint venture of Lockheed Martin and Boeing. ULA was formed in December 2006 by combining the teams at these companies which provide spacecraft launch services to the government of the United States. U.S...
joint venture. Each company has a 50% stake in ULA.
Launch services contracts
In October 1998 two initial launch services contracts (known as Buy 1) were awarded. Along with the award of two development agreements, the total amount was more than $3 billion. Boeing was awarded a contract for 19 out of the 28 launches; Lockheed Martin was awarded a contract for the other 9. Boeing received $1.38 billion, and Lockheed Martin received $650 million for the launches.In 2003 the USAF moved 7 launches from Delta IV to Atlas V.
Human-rating
In 2009 The Aerospace CorporationThe Aerospace Corporation
The Aerospace Corporation is a private, non-profit corporation headquartered in El Segundo, California that has operated a Federally Funded Research and Development Center for the United States Air Force since 1960...
reported to NASA results of study intended to determine the feasibility of modifying an EELV to be human-rated
Human-rating certification
Human-rated or man-rated are terms used to describe the certification of a spacecraft, launch vehicleor airplaneas worthy of transporting humans. NASA and the U.S. GAO now uses "Human-rating" when describing requirements for these systems...
for use in NASA human spaceflight
Human spaceflight
Human spaceflight is spaceflight with humans on the spacecraft. When a spacecraft is manned, it can be piloted directly, as opposed to machine or robotic space probes and remotely-controlled satellites....
missions. According to Aviation Week the study, "found that a Delta IV heavy [...] could meet NASA's requirements for getting humans to low Earth orbit." In a presentation to the Review of U.S. Human Space Flight Plans Committee, an Aerospace Corporation representative presented a summary of the study. The summary asserts that even without a newly developed upper stage, it would be feasible for a human-rated Delta IV Heavy to launch a crewed Orion
Orion (spacecraft)
Orion is a spacecraft designed by Lockheed Martin for NASA, the space agency of the United States. Orion development began in 2005 as part of the Constellation program, where Orion would fulfill the function of a Crew Exploration Vehicle....
spacecraft to the International Space Station
International Space Station
The International Space Station is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes...
. ULA has since published a paper detailing the changes needed for man-rating EELVs. On February 2, 2010 NASA awarded ULA $6.7 million in stimulus funds under the Commercial Crew Development
Commercial Crew Development
Commercial Crew Development is a multiphase space technology development program, funded by the U.S. government, and administered by NASA. The program is intended to stimulate development of privately operated crew vehicles to low Earth orbit. It is run by the Commercial Crew and Cargo Program...
(CCDev) program. A Space Act agreement
Space Act Agreement
Space Act Agreement is a type of legal agreement specified in the National Aeronautics and Space Act that established NASA. Agreements of this type have been reached under the Commercial Orbital Transportation Services and Commercial Crew Development programs are examples of Space Act agreements...
was set up to develop an Emergency Detection System
Emergency Detection System
An Emergency Detection System is a system that is used on manned rocket missions. It monitors critical launch vehicle and spacecraft systems and issues status, warning and abort commands to the crew during their mission to low Earth orbit. It can trigger the Launch Abort System which will take the...
(EDS) that could be used on both EELVs. An EDS monitors critical launch vehicle and spacecraft systems and issues status, warning and abort commands to the crew during their mission to low Earth orbit.
External links
- EELV on Global Security
- Lockheed Martin's Atlas V 400-series, Atlas V 500-series pages
- Boeing's Delta IV page
- United Launch Alliance (ULA) page