Simplified parametric cost trade-offs in satellite system design

In this paper, a parametric cost model for the space segment of a meteorological satellite system is derived and exercised to provide insight into the major economic trade-offs affecting the choice of the satellite's design life and replacement strategy. Trade-offs involving replacement strategy include launch via an expendable booster versus launch via the Space Shuttle; and recovery, repair, and reuse of a failed satellite versus simple replacement with no reuse.

The sensitivities of space segment costs to design life, launch costs, replacement costs, and refurbishment costs are examined with explicit inclusion of nonrecurring and recurring costs.

The results from an application of the model indicate that routine spacecraft retrieval and reuse of a modestly expensive spacecraft is not a significant economic benefit and that design lifetimes of three or four years are the best choice.     

Priorities in space for the USA

This article follows the story of Shuttle development, in the context of the history of the US space programme from Apollo to the Space Station. The Shuttle was chosen as one of a series of ‘space spectaculars’ and has proven to be prohibitively expensive and unreliable, practical only for a very limited number of specialized missions. The Space Station, too, cannot be economically supplied, even if the USA could afford to build it. The author concludes that NASA should cancel the Space Station and the replacement orbiter for Challenger, and engage on a major programme of launch vehicle development, independent of the US military. The aim should be a dramatic reduction of launch vehicle costs, making spaceflight practical, and a truly independent NASA which could restore the USA to space preeminence.     

Identification and status of design improvements to the NASA Shuttle EMU for International Space Station application

To meet the significant increase in EVA demand to support assembly and operations of the International Space Station (ISS), NASA and industry have improved the current Shuttle Extravehicular Mobility Unit (EMU), or "space suit", configuration to meet the unique and specific requirements of an orbital-based system. The current Shuttle EMU was designed to be maintained and serviced on the ground between frequent Shuttle flights. ISS will require the EMUs to meet increased EVAs out of the Shuttle Orbiter and to remain on orbit for up to 180 days without need for regular return to Earth for scheduled maintenance or refurbishment. Ongoing Shuttle EMU improvements have increased reliability, operational life and performance while minimizing ground and on-orbit maintenance cost and expendable inventory. Modifications to both the anthropomorphic mobility elements of the Space Suit Assembly (SSA) as well as to the Primary Life Support System (PLSS) are identified and discussed. This paper also addresses the status of on-going Shuttle EMU improvements and summarizes the approach for increasing interoperability of the U.S. and Russian space suits to be utilized aboard the ISS.     

阿里安5助推器回收系统

阿里安5是西欧正在研制的一种大型运载火箭。高度可靠和价廉是它的设计宗旨。发射以后,对助推器进行回收、修复并重复使用,是实现价廉目标的重要手段。文中对这种回收系统的技术要求、主要分系统及回收程序等作了简要介绍。     

Data on and methodology for calculating space shuttle programme costs

This report presents data on the annual and total costs of NASA's Space Shuttle programme through fiscal year (FY) 1993. The total cost of the programme through FY 1993 is found to be $83.7 billion in 1992 dollars. This information has significance for pending policy decisions on the future of the Shuttle programme, its possible successors, and interrelated programmes, such as the Space Station.     

航天飞机先进固体火箭发动机的推进剂

综述了美国航天飞机走进固体火箭发动机的推进剂配方研制，制造工艺和工艺过程中的质量控制。     

Potential cost reductions for three STS/Spacelab mission modes

Based on the results of studies carried out by ESA several possibilities are discussed to achieve mission cost reductions for large Spacelab instrument facilities as compared to their flight on several 7-day duration Spacelab missions. As an example three scientific telescope facilities are selected (LIRTS, EXSPOS, GRIST) which are defined to a Phase A level.Three new mission modes are considered:

• —Shuttle attached Spacelab mission mode with extended flight duration (up to 30 days) for which the application of planned capability extensions and new elements of the STS/Spacelab (e.g. Short Spacelab Pallets, Power Extension Package) are investigated.

• —Shuttle deployed mission mode, for which the telescope, accommodated on a Spacelab pallet, is docked to the Power Module, a new element of the Space Transportation System under study by NASA.

• —Free-flying mission mode, for which Shuttle launched dedicated missions of the facilities are considered, assuming varying degrees of autonomy with respect to supporting services of the Shuttle.

Reduction of costs have been considered on the levels of single mission cost and total programme cost. Fundamentally the charges for the instrument can be reduced by constraining the mass/volume factors with respect to the Shuttle capability. However, the instrument as part of a payload is only viable if an acceptable resource sharing including observation time can be achieved. Any single instrument will require several mission opportunities or one mission which achieves a similar or longer total observation programme.Based on an identification of instrument modifications of the Phase A baseline designs to favour cost reductions and on a derivation of technical requirements, constraints and finally budgetary cost comparisons an attempt is made to assess the advantages and disadvantages of the different mission modes.The favoured option for GRIST is a 2–3 weeks sortie mission followed after refurbishment by a longer Power Module docked mission. For LIRTS and EXSPOS the free-flying pallet modes are very attractive in terms of the longer durations achieved and in terms of cost per unit operating time.     

大型捆绑运载火箭姿态控制系统

本文介绍了大型捆绑运载火箭姿态控制系统方案、工作原理和首发飞行试验结果,并将部分参数同美国航天飞机进行比较。     

One year old and growing: a status report of the International Space Station and its partners.

The International Space Station (ISS), as the largest international science and engineering program in history, features unprecedented technical, cost, scheduling, managerial, and international complexity. A number of major milestones have been accomplished to date, including the construction of major elements of flight hardware, the development of operations and sustaining engineering centers, astronaut training, and eight Space Shuttle/Mir docking missions. International partner contributions and levels of participation have been baselined, and negotiations and discussions are nearing completion regarding bartering arrangements for services and new hardware. As ISS is successfully executed, it can pave the way for more inspiring cooperative achievements in the future.     

运载火箭交叉输送系统关键影响因素辨识与分析

为深入了解交叉输送系统特性，辨识关键影响因素及其影响规律，通过系统建模与仿真分析开展交叉输送系统关键影响因素研究。推导了交叉输送系统关键组件数学模型，基于AMESim软件构建了系统仿真模型。研究表明，贮箱气枕压差和输送管路流阻是两大关键影响因素。为保证推进剂按额定流量交叉输送，必须对各子级箱压进行精确调节。由于助推上游主管路和交叉输送管路流阻对系统性能影响较大，在设计交叉输送系统时应该尽量缩短助推上游主管路和交叉输送管路，并尽量减小不同助推的管路流阻偏差。     

The future of human spaceflight.

After the Apollo Moon program, the international space station represents a further milestone of humankind in space, International follow-on programs like a manned return to the Moon and a first manned Mars Mission can be considered as the next logical step. More and more attention is also paid to the topic of future space tourism in Earth orbit, which is currently under investigation in the USA, Japan and Europe due to its multibillion dollar market potential and high acceptance in society. The wide variety of experience, gained within the space station program, should be used in order to achieve time and cost savings for future manned programs. Different strategies and roadmaps are investigated for space tourism and human missions to the Moon and Mars, based on a comprehensive systems analysis approach. By using DLR's software tool FAST (Fast Assessment of Space Technologies), different scenarios will be defined, optimised and finally evaluated with respect to mission architecture, required technologies, total costs and program duration. This includes trajectory analysis, spacecraft design on subsystem level, operations and life cycle cost analysis. For space tourism, an expected evolutionary roadmap will be described which is initiated by short suborbital tourism and ends with visionary designs like the Space Hotel Berlin and the Space Hotel Europe concept. Furthermore the potential space tourism market, its economic meaning as well as the expected range of the costs of a space ticket (e.g. $50,000 for a suborbital flight) will be analysed and quantified. For human missions to the Moon and Mars, an international 20 year program for the first decades of the next millennium is proposed, which requires about $2.5 Billion per year for a manned return to the Moon program and about $2.6 Billion per year for the first 3 manned Mars missions. This is about the annual budget, which is currently spend by the USA only for the operations of its Space Shuttle fleet which generally proofs the affordability of such ambitious programs after the build-up of the International Space Station, when corresponding budget might become again available.     

Shuttle avionics verification and integration testing

The Space Shuttle Orbiter employs a fly-by-wire control system of 200 major avionic hardware devices interfacing with five flight computers through a complex data bus system. Responses to man-in-the-loop commands are dependent on the flight software. Early program development testing of the computer and avionic hardware has been accomplished at Rockwell International's Shuttle Avionics Development Laboratory (ADL). Hardware development has led to complete multi-string system testing and flight software evaluations. This paper provides an overview of the ADL. Its role and test capabilities in support of Shuttle development are defined. The nature of computer driven test programs for the Orbiter displays, the Digital Autopilot, and flight software development describe the test bed provided by the ADL.     

Past, present, and future: the U.S. EVA program

This paper provides an overview and summary of U.S. extravehicular activity accomplishments of the last 26 years, Space Shuttle missions having scheduled extravehicular activities to be performed over the next several years, extravehicular activities expected to be necessary to support Space Station Freedom assembly tasks and operations, and potential extravehicular activity roles of the NASA Space Exploration Initiative Program.     

Economic benefits of the OTV program

A new upper stage for the Shuttle called Orbiter Transfer Vehicle (OTV) is planned by the National Aeronautics and Space Administration (NASA) for a broad range of missions including transfer of very large spacecraft, unmanned and manned servicing at Geosynchronous orbit (GEO). Leading OTV configurations use 13 to 34 tonnes of cryogenic propellants in vehicles based on the existing Centaur or new designs. These OTVs can deliver to Geosynchronous orbit more than double the payload possible with the solid propellant Intertial Upper Stage (IUS), which is currently being developed. This high performance reduces the number of shuttle launches required to deliver a given total mass of payloads. After delivery of current size spacecraft, OTV could be returned to the Orbiter for reuse, saving the cost of building a new stage. OTV performance and flexibility will create the opportunity for the next generation of spacecraft such as Geostationary Platform. In these three ways, the high-performance OTV will provide economic benefits to Space Transportation Systems.     

A practical approach to the disposal of highly toxic and long-lived spent nuclear fuel waste between Venus and Earth

Extraterrestrial disposal, while not the only alternative (there is at least one very safe terrestrial method), nevertheless assures definite and irreversible removal of the most toxic and long-lived waste from the biosphere. In the foreseeable future, there is far less need to retrieve nuclear waste for later use then to dispose of it in a publicly acceptable manner, beginning in the near future (middle 1980s). It is, therefore, more important to assure safety in the weakest link of this disposal process—transportation into near-Earth orbit—than to engage in a retrievable disposal beyond Earth. The disposal “site” should lie at minimum safe transfer energy level. Primary candidate is the space between Venus and Earth. The number of propulsion phases should be a minimum, preferably only one (out of near-Earth orbit). Lunar gravity assist can be helpful to achieve higher inclination of the heliocentric orbit relative to the ecliptic.Solidified spent fuel isotopes and actinides, sufficient to reduce the residual terrestrial waste to the radiation level of natural uranium deposits after 30–40 yr instead of 1000–1500 yr, is deposited into heliocentric orbits. Transportation systems, requirements, costs and the associated socio-economic benefit potentials of an environmentally more benign and a more vigorous nuclear power generation program are presented.Prior to solidification, an interim storage of 10 yr, following removal from the reactor, may be required. The Shuttle, with one Orbiter modified as Nuclear Waste Carrying Orbiter (NWCO) and an out of near-Earth orbit booster, provides a safe and economic transportation system at (1979$) disposal mission costs from surface to disposal orbit of less than $\text{0.5¢/}\text{kWhe or}\text{? 0.1¢/}\text{kWhe}$ (some 70% of overall exo-disposal cost), depending on level of orbital operations (this at basic Shuttle flight cost of $30M). The orbital operations mode can be selected according to lead time and costs, and can be advanced sequentially, lowering disposal costs while at the same time financing the development of orbital operations techniques needed also for other and larger-scale exo-industrial activities. An average of 10–15 disposal missions of the NWCO is required annually, at the given conditions, to service the spent fuel of 173 reactors 1978 in operation in W. Europe, Japan and North America.     

Space platforms: A cost effective evolution of Spacelab operation

The Shuttle/Spacelab mode of space operations will soon provide ready access to space for a wide varity of experimenters. When the full capabilities of this system are utilized, an important tool will have been added to the research and development phases of the various disciplines. Although significant benefits can now be envisioned from using these systems, it has become evident that additional benefits to the users could be achieved if some of the available resources were augmented. Those resources include: power, thermal control; duration on orbit; stability; and orientation.This paper reports planning efforts in progress to determine what augmentation these systems should provide. To properly bound the study effort, a projection of the potential Spacelab activity through the 1980 decade is developed. Three major augmentation systems are examined and the benefits provided by each are outlined. One of these systems, the Science and Applications Space Platform, represents a very attractive concept and the potential cost effectiveness is examined in detail. After these analyses are completed, general conclusions on the cost and other benefits of Space Platforms are provided.     

Using Spacelab as a precursor of science operations for the Space Station

For more than 15 years, Spacelab, has provided a laboratory in space for an international array of experiments, facilities, and experimenters. In addition to continuing this important work, Spacelab is now serving as a crucial stepping-stone to the improved science, improved operations, and rapid access to space that will characterize International Space Station. In the Space Station era, science operations will depend primarily on distributed/remote operations that will allow investigators to direct science activities from their universities, facilities, or home bases. Spacelab missions are a crucial part of preparing for these activities, having been used to test, prove, and refine remote operations over several missions. The knowledge gained from preparing these Missions is also playing a crucial role in reducing the time required to put an experiment into orbit, from revolutionizing the processes involved to testing the hardware needed for these more advanced operations. This paper discusses the role of the Spacelab program and the NASA Marshall Space Flight Center- (MSFC-) managed missions in developing and refining remote operations, new hardware and facilities for use on Space Station, and procedures that dramatically reduce preparation time for flight.     

The shuttle development and its growth potential

During the next two decades, we will establish the foundation for the 21st century's accomplishments in space. The Space Shuttle vehicle will become the cornerstone for that foundation by providing economical opportunities for space exploration and utilization.Reusability of the Shuttle vehicle is the key to its economy. The major developmental challenges encountered in the Shuttle program are typified by the complexities involved in designing the reusable propulsion and thermal protection subsystems. We successfully met such challenges and are nearing the launch of the first Shuttle orbital flight.Our immediate goal is to enter the Space Shuttle operational phase because only then will we fully understand the unique capabilities of the Shuttle. Concurrent with our effort to begin Shuttle operations are our initial efforts to expand Shuttle capabilities, extending them significantly beyond those of the current baseline system.Shuttle payload capacity and mission-duration capabilities are to increase considerably during the next decade. Just as present Shuttle performance specifications and development timetables were guided by the space program plans and forecasts of the 1960s, so will the development of long-range space programs be determined by our near-future achievements. We anticipate that the Space Shuttle will play a critical role in those achievements.     

Development of the RFBB “Bargouzine” concept for Ariane-5 evolution

This paper presents the study of a concept of Ariane-5 evolution by means of replacement of two solid-propellant boosters EAP with two liquid-propellant reusable fly-back boosters (RFBBs) called “Bargouzine”. The main design feature of the reference RFBB is LOX/LH2 propellant, the canard aerodynamic configuration with delta wings and rocket engines derived from Vulcain-2 identical to that of the central core except for the nozzle length. After separation RFBBs return back by use of air breathing engines mounted in the aft part and then landing on a runway.The aim of the study is a more detailed investigation of critical technology issues concerning reliability, re-usability and maintenance requirements. The study was performed in three main phases: system trade-off, technical consolidation, and programmatic synthesis. The system trade-off includes comparative analysis of two systems with three and four engines on each RFBB and determination of the necessary thrust level taking into account thrust reservation for emergency situations. Besides, this phase contains trade-off on booster aerodynamic configurations and abort scenario analysis.The second phase includes studying of controllability during the ascent phase and separation, thermo-mechanical design, development of ground interfaces and attachment means, and turbojets engine analysis taking into account reusability.