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The Evolved Expendable Launch Vehicle program, born of studies conducted in the late 1980s and 1990s, represents a commitment to significantly reducing the cost of access to space. An industry/government partnership is developing two competing EELV systems to meet space transportation needs over the next 20 years. Conceived as a “system of systems” to improve operability and reduce recurring costs, EELV is using streamlined manufacturing and improved mission assurance pro-cesses. Its facilities and operations also are being designed to lower costs. Requirements call for a 25-50% reduction in recurring operational cost compared to current systems, and for improving system reliability and availability.
EELV is using CAIV (cost as an independent variable) to achieve these savings (see “EELV meets CAIV,” Aerospace America, May 1999, page 68). The program implements DOD acquisition excellence goals by streamlining the government’s role and replacing its oversight of contractors with less intrusive “insight.” This approach shifts greater responsibility to the providers, allowing them wider freedom to determine the pro-cesses, methods, and resources with which they will satisfy requirements. The objective is to enhance U.S. launch industry competitiveness in the international market by reducing costs across the entire system.
EELV comprises two families of launch vehicles, infrastructure, support systems, interfaces, mission integration, and launch operations activities. Evolved from current ELV systems and new applications of existing technology, EELV will support U.S. military, intelligence, civil, and commercial mission requirements using contractor-provided commercial launch services. The two are the Lockheed Martin Atlas V and Boeing Delta IV, both designed to meet the full range of government launch requirements.
The EELV program has three key performance parameters: specific payload mass-to-orbit requirements; vehicle design reliability of 0.98 (threshold) at 50% confidence level; and standardization, including standard payload interface for each class of vehicle and standard launch pads that can accommodate all configurations in an EELV family.
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Atlas V
The Atlas V family of vehicles is built around a structurally stable Common Core Booster (CCB) powered by the Russian RD-180 engine. The RD-180 is produced by RD AMROSS, a joint venture between Pratt & Whitney and Russia’s NPO Energomash. The engine develops 860,000 lbf of thrust at sea level, uses liquid oxygen/RP-1 propellants, and is the only high-thrust staged combustion liquid oxygen/RP-1 engine in production. It has been tested extensively and was flight proven on the first Atlas IIIA mission in May 2000.
Atlas V’s several configurations have the flexibility to meet varied performance requirements for missions from LEO to GTO. Options include the addition of one to five Gencorp Aerojet strap-on solid rocket motors for intermediate lift capability or the use of three CCBs for heavy payloads. The Atlas 400 series has a 4-m payload fairing and a single CCB; the 500 series has a composite 5.4-m payload fairing, a single CCB, and up to five Aerojet solid rocket boosters; and the heavy launcher has three CCBs and a composite 5.4-m payload fairing. All three series use a common Centaur upper stage with Pratt & Whitney RL10A-4-2 engine(s).
The Atlas family will have GTO lift capability of up to 29,500 lb. Atlas V, which uses the same Centaur upper stage as the Atlas IIIB, can be configured with either one or two RL10A-4-2 engines. A hydrazine attitude control system provides precise on-orbit maneuvering. The 5.4-m payload fairing is a new design derived from the Ariane V fairing manufactured by Contraves Space of Switzerland. It will be offered in two lengths, one optimized for communications satellites and the other for accommodating large-volume spacecraft missions. The 4-m payload fairing is the same one used with Atlas II and III and is manufactured in Harlingen, Texas.
Among Atlas V’s innovations is the RD-180 engine’s capability for continuous throttle between 47% and 100% of nominal thrust, which allows for substantial control over launch vehicle and payload environments. Others include reduced manufacturing cycle time and simplified launch processing. Atlas V also includes the Air Force EELV standard payload interface, allowing payload interchangeability with Delta IV.
Atlas V launch service is normally completed within 24 months of order. Payload integration, data exchanges, reviews, schedules, and operations are fully documented and consolidated for each mission in CD-ROM Launch Services Plans, which provide a detailed roadmap of all relevant activities.
To improve operability and reliability, system development has taken a low-risk, evolutionary approach, beginning with a design that uses common elements such as the RD-180, CCB, Centaur, and avionics. Lockheed Martin has introduced new elements gradually rather than attempting to develop and fly an entirely new vehicle. Heritage hardware is augmented by extensive development testing of new or modified Atlas V hardware. The successful Atlas IIIA flight in May 2000 demonstrated many Atlas V subsystems, as will Atlas IIIB.
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| The heart of the Atlas V family is the Common Core Booster.
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Manufacturing and processing
One tenet of Atlas V’s streamlined manufacturing is designing producibility into the system from the beginning. Production engineers are placed on the contractor’s integrated product teams to improve this aspect of the design and enhance work flow.
The Air Force has emphasized use of statistical techniques for analyzing and measuring the variations of processes. Lockheed Martin is reducing cycle time by using lean manufacturing and “Six Sigma” tools to eliminate wasted activity and focus on predict-able processes. Atlas cycle times have been cut from 47 months to 20 months. Manufacturing processes and product integrity are managed via process capability metrics measured against defects per million opportunities. Key processes are under control and show continuous variability reduction.
The company is also using Kaizen principles, which call for continuous improvement to eliminate waste in all the systems and processes of an organization without large capital expenditures.
In another new approach, Atlas V hardware will be transported to the launch site in a flight-ready configuration, completely tested at the factory before shipment. In general, this means all components are installed at the factory and not at the launch site.
Atlas V incorporates efficient launch site processing, including use of an off-pad Vertical Integration Facility (VIF) for the vehicle and parallel processing of the encapsulated payload in separate installations. Launch site processing has been reduced from the 28-38 days for Atlas II to just 18-26 days. The encapsulated payload will be transported to the VIF and mated to the launch vehicle. After combined systems testing, the fully integrated Atlas V/encapsulated payload will be transported to the nearby “clean launch pad.” All vehicle configurations use common processing procedures and can be launched from the same clean pad. On-pad time has been reduced to less than one day.
Atlas V system activation and development checkout operations are currently under way in Space Launch Complex-41 at Cape Canaveral Air Force Station.
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Delta IV
Delta IV, built around a 16.7-ft-diam Common Booster Core (CBC), is powered by the new Boeing-Rocketdyne RS-68 main engine. This 650,000-lbf-thrust engine, fueled by liq-uid oxygen/liquid hydrogen propellants in a basic gas generator cycle, uses no new tech-nology. The vehicle’s cryogenic upper stage, which uses the Pratt & Whitney RL10B-2 engine, is substantially similar to that flown on the Delta III.
The Delta IV vehicle family will have a GTO lift capability of up to 29,500 lb and is available in three major variants. The med-ium-class vehicle consists of one CBC, a 4-m cryogenic upper stage, and a 4-m payload fairing. Intermediate, or medium-plus, vehicles are comprised of a single CBC, two or four Alliant Techsystems strap-on solid rocket motors (graphite epoxy GEM-60), a 4-m or 5-m upper stage, and a 4-m or 5-m payload fairing. The third, heavy lift variant comprises three CBCs, a 5-m upper stage, and a 5-m fairing—either an isogrid aluminum fairing based on the existing Titan IV, or a newly developed composite fairing. The 4-m fairing is the existing Delta III composite fairing lengthened by 3 ft.
Improvements include the new CBC, newly developed and simplified main cryogenic engine, Focused Factory facility, and simplified launch processing operations.
Parts for the medium-plus and heavy CBCs are, respectively, 88% and 93% common relative to the medium CBC. All are manufactured using a common factory production line. CBC innovations include friction stir-welded tanks, spun-formed domes, and use of composite structures. The RS-68 has reduced operating pressure, 80% lower parts count, 95% less labor, use of cast versus welded parts, and no special coatings. However, over 85% of the upper-stage part count is Delta III heritage, and much of the avionics are from Delta II and III.
The Delta IV launch service is also accomplished within 24 months of launch order. All activities required for executing the launch service are completely documented and consolidated for each mission in CD-ROM and Web-based Integrated Mission Services Plans. Like Atlas V, the Delta IV also includes the EELV standard payload interface.
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| The Delta IV is built around a 16.7-ft-diam Common Booster Core.
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Development and operations
Boeing has taken an evolutionary approach to Delta IV development, balancing the use of new and heritage hardware. New developments include the RS-68 main propulsion system, which involves extensive testing of major components to verify parameters such as thrust, specific impulse, mixture ratio, and main combustion chamber pressure.
Delta IV is manufactured mainly in Decatur, Ala., at Boeing’s new Focused Factory, which uses lean manufacturing and optimized workflow processes. Production personnel participate in the design integrated process teams from the outset. Reduced touch labor enhances reliability and reduces chances for human-induced damage.
Boeing has partnered with the Air Force to emphasize use of statistical techniques for analyzing and measuring the variations of processes. Key manufacturing processes at Decatur are managed using process capability metrics. Full integration, assembly, and checkout testing take place before each vehicle leaves the factory. Delta IV’s horizontal booster processing flow and vehicle stage mating in the Horizontal Integration Facility allow for parallel integration, reduced hazardous lifting operations, and decreased pad time. Total vehicle time at the launch base is less than one month, with only 8-11 days on the pad. Each pad can launch all configurations, and launch pads are virtually standard between the Cape Canaveral SLC-37 and Vandenberg AFB SLC-6 launch sites.
Market realities
For many reasons, the commercial satellite market declined sharply between late 1997 and 2001. Nevertheless, the EELV acquisition strategy continues to rely on the strong commercial viability of Delta IV and Atlas V, as well as contractor motivation to maximize performance and market potential. Because of the reduced need for launch capacity from Vandenberg AFB, Atlas V will now operate only from Cape Canaveral rather than from both sites. The government also restructured slightly the allocation of missions to each contractor.
Softening launch demand also led to a reduction in the number of commercial Atlas V and Delta IV launches to be flown prior to U.S. government launches, which had been part of the original risk reduction approach. Because of several launch failures from 1997 to 1999, the government initiated reviews that evaluated potential causes across all launch systems and recommended corrective actions. As a result, additional mission assurance steps were taken across all U.S. launch systems, including EELV.
Mission assurance comprises all activities that establish confidence that the risk of failure of a particular mission is acceptably low and that success is maximized. These activities span the entire technical continuum, from design and development through launch and postflight analyses. Mission assurance will rely heavily on the cooperation of each provider with the government. These relationships result from the unique EELV contracting and launch service procurement approach.
In partnership with Boeing, the government is procuring a demonstration launch of the Delta IV heavy lift vehicle to reduce risk and improve mission assurance.
The approach to independent risk assessment will also be enhanced. EELV Independent Risk Assessment Teams will be active from the start of the mission integration process. Their efforts will be part of the EELV launch service but will proceed in parallel with program launch verification pro-cesses, which are the responsibility of the EELV program office. Launch verification will ensure that all relevant requirements are met and all anomalies resolved. The teams will then independently evaluate the highest risk items as part of launch readiness.
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EELV remains firmly on the course set in 1995 to develop improved launch capability at reduced cost. As U.S. heritage systems are phased out, EELV will furnish the primary U.S. expendable launch capability for the next 20 years, and will continue to provide a sound transition to any future reusable launch vehicle systems.
EELV history
In August 1995, the U.S. government awarded $30-million contracts to four companies, with the aim of ultimately selecting one EELV builder. In December 1996, it down-selected to two, McDonnell Douglas (subsequently acquired by Boeing) and Lockheed Martin. As the ratio of government to commercial launches shifted significantly toward commercial, the Air Force revised its plan to allow both contractors to proceed into engineering, manufacturing, and development (EMD).
In October 1998, the government awarded $500 million each to Lockheed Martin and Boeing. Development costs are shared between the contractors and the government, resulting in a national, dual-use launch service. By using very small integrated product teams interfacing directly with the contractors, the government is moving away from its traditional role of conducting oversight from large program offices. The EMD module gives the government detailed acquisition data and system development insight from both contractors. The government program office has virtually unlimited access to all but some highly sensitive and proprietary cost and pricing data.
The Air Force simultaneously awarded initial launch service contracts to both firms: $1.38 billion to Boeing for 19 launches and $650 million to Lockheed Martin for nine launches. These contracts also had several innovative features. For example, the government bought only launch services, not hardware. In addition, some provisions allowed for cost-effective launch postponements or delays if needed, and guaranteed the most competitive pricing for U.S. government launches.
The strategy enabled two further benefits: competition and assured access to space. Competition throughout the life cycle of the program is key to achieving the 25% reduction in recurring cost. And two providers using a standard payload interface maintain payload interchangeability between Atlas V and Delta IV and enhance assured access to space.
Common terms and conditions define the commercial business relationship and apply to all EELV launch services. Benefits include a single standard of quality, full funding traceability by mission and source of funds, quantity discounts for economically efficient buys, a single streamlined government-to-contractor interface, and real-time sharing of lessons learned. Each launch service is carried out via a separate contract delivery order with its own mission-unique statement of work and specifications established by the mission owner. Each delivery order for a launch service has a standard 24-month period of performance. Individual launch services plans, however, are highly flexible and can be tailored to spacecraft customer needs.
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