Evolved Expendable Launch Vehicle Research Articles

Design, Analysis, Test, and Model Correlation of a Flight-Like Additively Manufactured ESPA-Class Satellite

This paper presents the design, finite element analysis, dynamic testing, and model correlation of AdditiveSat, an additively manufactured Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (ESPA)–class spacecraft fabricated using fused filament fabrication. The AdditiveSat octagonal prism design incorporates several known additive manufacturing benefits, such as secondary structure printed directly into the primary structure and thus reducing the number of parts required to assemble the vehicle. A Pathfinder structure was printed and sine burst tested to , as well as random vibration, to demonstrate the feasibility of an additively manufactured ESPA-class structure to survive flight launch environments. A detailed model correlation effort noted several best practices for finite element models in order to generate acceptable dynamic predictions for this type of architecture. The final correlated model accurately predicts the frequency of major structural modes of the Pathfinder structure within 3% and also provides accurate predictions for high-frequency responses up to 1000 Hz.

Interim Access to the International Space Station Using Evolved Expendable Launch Vehicles

This paper explores mission scenarios using existing evolved expendable launch vehicles for delivering, on an interim basis, the crew exploration vehicle Orion to the International Space Station. The use of existing commercial launchers is proposed to narrow the International Space Station service gap from the time the space shuttle is deserviced until the new Ares I launch vehicle is crew rated and operational. Here, three launch options are evaluated:1)theAtlasVheavy-liftvehicle,2)theDeltaIVheavy-lift vehicle,and3)theDeltaIVwiththreecommoncore boosters (as a first stage, with the Orion acting as the second stage). Configurations 1 and 3 require significant impulse from the Orion’s service-module engine to achieve the final orbit. Configuration 2 launches the Orion as a passivepayload,withoutrelianceonanyimpulse fromtheservicemodule.Allthreeconfigurations reservesufficient service-module impulse for deorbit and reentry. Detailed simulation results, concepts of operation, and mission timelines are presented for each configuration. Mission feasibility is demonstrated for all three configurations. The final configuration has the advantage of eliminating failure paths and requiring human rating only for the commoncore booster on the Delta IV system. Finally, reliability- and development-cost assessments are presented and compared with the Ares I.

Lunette: A low-cost concept enabling multi-lander lunar science and exploration missions

The development of low cost missions for lunar exploration has emerged as a topic of increasing interest. Recently a study team from JPL was tasked to consider potential high-value lunar surface science and exploration missions that could be performed with small, low cost landed assets, with particular emphasis on missions that could be flown as secondary payloads on evolved expendable launch vehicle (EELV) launches. A mission concept and flight system design was developed in the course of this study that would deliver a network of up to six individual landers to a local lunar region, utilizing the full capabilities of the EELV secondary payload adapter (ESPA). The braking burn of the six landers would be performed by a single solid rocket motor integral with the ESPA ring, following which the landers would separate from the ESPA and perform final descent and precision landing using their own onboard propulsion systems. The six landers would initiate a one year mission, performing site survey and environmental science measurements including illumination, temperature, radiation, soil mechanics, and seismometry. Additional payload accommodation would be available on each lander to include unique experiments. The lander design was constrained to fit within the requirements for accommodation on the ESPA. These include a wet mass of no more than 180 kg, and dimensions that fit in an envelope of 61×71×96 cm. The total landed mass of the conceptual spacecraft is ∼140 kg which would deliver a total of ∼15 kg of payload mass to the lunar surface, per lander. In addition to the multi-lander ESPA-based design, a single lander flight system variant was developed that could enable globally distributed network science at very low cost. This paper discusses the mission concepts, flight system designs and numerous system engineering challenges that led to the development of this uniquely flexible and cost effective lunar mission concept.

1.5.2 Emerging Real‐Time Intelligent Agents In Space Launch Verification and Anomaly Resolution

AbstractIn 1997, the Evolved Expendable Launch Vehicle (EELV) program, now under the auspices of the United Launch Alliance (ULA), began with fundamental goals to reduce cost and improve the reliability of launching satellites and interplanetary spacecraft. With payloads costing more that several billion dollars each, the reliability of launch vehicles mandates perfect launches. Subsequently, launch systems have become highly complex with increasing launch rates of satellites to perform surveillance, network‐centric command and control, and communications on the land, sea, air and space. Launch system Ground Computers, Command and Control (GC3) has grown exponentially in software capabilities, collecting and displaying data to domain experts, and transmitting real‐time data to world‐wide support teams. Rapid and accurate anomaly resolution with customers and contractors, especially for events leading up to day‐of‐launch (DOL) involves hundreds of personnel using these complex systems. This paper describes near‐term capabilities which are the building blocks of future intelligent agents: decision making, knowledge management; computer systems, control software and desktop PC tools. These agents are rapidly maturing into integrated systems decision making processes that are responsive within seconds. This near‐term development activity is compared with a 20‐year forecast of spaceport intelligent agent systems.

Access to Space: A Strategy for the Twenty-First Century

The United States (US) launch infrastructure is at a crisis point. Human access to space embodied in the Space Shuttle is due to be phased out by 2010. Currently, there are no heavy lift, 100 ton class launchers to support the US national vision for space exploration. Medium and large expendable launch providers, Boeing's Delta IV, and Lockheed-Martin's Atlas V Evolved Expendable Launch Vehicles are so expensive that the Delta no longer carries commercial payloads and the Atlas is unlikely to show significant growth without equally significant cost reductions and commercial traffic growth. This set of circumstances questions US dependence on these launch vehicles for national security purposes. High cost growth also exists with small launch vehicles, such as Pegasus, and the promising new field of small and microsatellites is little developed in the US, while foreign efforts, particularly European, are expanding largely on the availability of low-cost Russian boosters. One bright point is the emerging private sector, which is initially pursuing suborbital or small lift capabilities. Although such vehicles support very limited US Department of Defense or National Aeronautics and Space Administration spaceflight needs, they do offer potential technology demonstration stepping stones to more capable systems needed in the future of both agencies. This article outlines the issues and potential options for the US Government to address these serious shortcomings.

Baseline design of new horizons mission to Pluto and the Kuiper belt

The New Horizons mission is progressing toward its planned launch in January 2006. Current plans call for the New Horizons spacecraft to be launched by a newly developed evolved expendable launch vehicle (EELV) Atlas V 551 with the STAR 48B kick stage in January/February 2006. After flying for more than 32 AU and traveling through the inner and outer solar system, the spacecraft is expected to arrive at Pluto as early as July 2015 for the first scientific reconnaissance investigations of the last planet that has not yet been visited by a spacecraft. This paper describes the baseline mission design, which includes the baseline launch scenario that maximizes the launch probability with an extensive launch period of 35 days, the interplanetary trajectory design that allows the spacecraft to fly fast to Pluto by taking advantage of the gravity assist from Jupiter, the trajectory design of the close encounter with Pluto and its moon Charon, and the mission plan for the extended mission beyond Pluto to fly by a Kuiper belt object. Note: New Horizons is NASA's planned mission to Pluto and has not been approved for launch. All representations in this paper are contingent on a decision by NASA to go forward with the preparation for and launch of the mission.

Evolved expendable launch vehicle system: RS-68 main engine development

Delta IV is one of two competing Evolved Expendable Launch Vehicle (EELV) systems being developed in an industry/United States Government partnership to meet the needs of the new era of space launch for the early decades of the 21 st Century. The Rocketdyne Division of The Boeing Company and the United States Air Force have developed a 650 Klbf sea-level (2.9 MN) class liquid hydrogen/liquid oxygen main engine for the Delta IV family of EELV. The purpose of this paper is to present the innovative approach to the design, development, testing and certification of the RS-68 engine.

Funding US access to space

The successful 20 November 2002 launch of Boeing's Delta IV satellite launch vehicle owes much to the US government's Evolved Expendable Launch Vehicle (EELV) programme, which is designed to establish an affordable means of securing access to space. Launchers built under the EELV programme will be used to introduce a new generation of US surveillance and reconnaissance satellites, which are seen as complementary to the unmanned aerial vehicle platforms recently lauded after their performance in the 'war on terror'. However, the production of new reconnaissance satellites, and their launch vehicles, has been subject to funding-related problems that could complicate their introduction into service.

A space transportation architecture for the future

This paper summarizes the results of recent studies by Orbital to significantly reduce NASA's future launch costs and improve crew safety through the implementation of a low-risk, evolutionary space transportation architecture. These studies were performed as a part of NASA's Space Transportation Architecture Studies (STAS). The STA studies were commissioned by NASA Headquarters to advise NASA and the Executive Office of the President on the future direction of U.S space transportation. A large number of vehicles and architecture approaches were examined and evaluated. Orbital's recommended architecture includes a small, multifunctional vehicle, referred to as a Space Taxi TM, which would serve as: an emergency crew return vehicle for the International Space Station (ISS), a two-way human space transportation system, a small cargo delivery and return vehicle, and a passenger module for a future Reusable Launch Vehicle (RLV). The Space Taxi would initially be launched on a heavy-lift Evolved Expendable Launch Vehicle (EELV), currently under development by U.S. industry and the U.S. Air Force. Together with a small cargo carrier located behind the Space Taxi, this combination of vehicles would be used to meet future ISS servicing requirements. Later, a two-stage, commercially developed RLV would replace the EELV in launching the Space Taxi system at a significantly lower cost. This RLV system will provide NASA and other customers with unprecedented reductions in cost and improvements in reliability, safety, and performance.

2 Integrating Government and Commercial Requirements – Serving Two Masters

ABSTRACTThe world market for launching satellites increased dramatically during the Preliminary Engineering and Manufacturing Development Phase of the United States Government's Evolved Expendable Launch Vehicle procurement program. This coincided with the U.S. Government's increased emphasis on acquisition reform ‐ insight versus oversight. These events brought about the following issues: Development funds could only support a single design for both government and commercial customers, Government and commercial requirements needed to be merged, The government needed assurance that its requirements would be preserved, and Government insight requirements had to be satisfied. The Boeing Company integrated and managed the Government Evolved Expendable Launch Vehicle (EELV) System Performance Requirements (SPR) and the Boeing commercial customer launch requirements into the Boeing Delta IV launch system development program. This paper describes the organization of the specification tree, the integration and flow‐down of requirements, requirements change management, the requirements verification, and the lessons learned from these activities.

Effects of high temperatures on human beings

Delta IV is one of two competing Evolved Expendable Launch Vehicle (EELV) systems being developed in an industry/United States Government partnership to meet the needs of the new era of space launch for the early decades of the 21st Century. The Rocketdyne Division of The Boeing Company and the United States Air Force have developed a 650 Klbf sea-level (2.9 MN) class liquid hydrogen/liquid oxygen main engine for the Delta IV family of EELV. The purpose of this paper is to present the innovative approach to the design, development, testing and certification of the RS-68 engine.