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1.
《Acta Astronautica》2008,62(11-12):1076-1084
Over the past fifteen years, major U.S. initiatives for the development of new launch vehicles have been remarkably unsuccessful. The list is long: NLI, SLI, and X-33, not to mention several cancelled programs aimed at high speed airplanes (NASP, HSCT) which would share some similar technological problems.The economic aspects of these programs are equally as important to their success as are the technical aspects. In fact, by largely ignoring economic realities in the decisions to undertake these programs and in subsequent management decisions, space agencies (and their commercial partners) have inadvertently contributed to the eventual demise of these efforts.The transportation revolution that was envisaged by the promises of these programs has never occurred. Access to space is still very expensive; reliability of launch vehicles has remained constant over the years; and market demand has been relatively low, volatile and slow to develop. The changing international context of the industry (launching overcapacity, etc.) has also worked against the investment in new vehicles in the U.S. Today, unless there are unforeseen technical breakthroughs, orbital space access is likely to continue as it has been with high costs and market stagnation.Space exploration will require significant launching capabilities. The details of the future needs are not yet well defined. But, the question of the launch costs, the overall demand for vehicles, and the size and type of role that NASA will play in the overall launch market is likely to influence the industry. This paper will emphasize the lessons learned from the economic and management perspective from past launch programs, analyze the issues behind the demand for launches, and project the challenges that NASA will face as only one new customer in a very complex market situation. It will be important for NASA to make launch vehicle decisions based as much on economic considerations as it does on solving new technical challenges.  相似文献   

2.
《Acta Astronautica》2001,48(5-12):869-883
Improvements in the safety, reliability and affordability of current and future space transportation systems must be achieved if NASA is to perform its mission and if the U.S. space industry is to reach its full potential. In response to Presidential Policy in 1994, NASA, working with our industrial partners, initiated several efforts including the X-33, X-34, X-37 and Advanced Space Transportation programs with the goal of demonstrating the technologies that could enable these goals. We have learned that emerging technologies will enable the needed advancements but that more development along multiple, competing paths is needed. We have learned that developing requirements diligently and in partnership with industry will allow us to better converge with commercial capabilities. We have learned that commercial markets are not growing as fast as projected earlier, but there are still possibilities in the near-term to pursue alternate paths that can make access to space more robust. The goal of transitioning NASA's space transportation needs to commercial launch vehicles remains the key aim of our efforts and will require additional investment to reduce business and technical risks to acceptable levels.  相似文献   

3.
介绍了国际航天发射市场及运载火箭的应用情况,根据美国的航天发射层次、国际航天发射市场的发射价格、国外对发射市场的需求,详细地分析了我国“长征”系列中型载火箭的应用和发展前景。  相似文献   

4.
This article discusses the economics of the demand for and supply of launch vehicles. Demand is derived from both commercial and governmental uses of space, while the supply of launch vehicles is determined by governmental needs which are rarely based on economic criteria alone. Multipurpose launches such as the Space Shuttle should be viewed as a national resource instead of a profit-seeking venture. Because of the mixing of government and private uses for space vehicles, traditional economic analysis provides only a starting point for policy decisions.  相似文献   

5.
Solid-propellant and liquid-propellant launch vehicles have their own characteristics, both playing an important role in space transportation systems of space powers. This paper reviews and summarizes the development history of solid-propellant launch vehicles, and analyzes their technical characteristics including multiple stages, large payloads, complex separation, diverse operation modes, fast response, and mission adaptability as well as unique advantages in launch activities. This paper analyzes and proposes four development laws for solid-propellant launch vehicles, including improving comprehensive performance, infusing heritage with innovation, unitization and seriation, and optimizing power systems. Finally, this paper proposes the opportunities and challenges faced by solid-propellant launch vehicles based on market demands.  相似文献   

6.
Like the other great space powers of the 21st century, Europe has its own means of accessing space: Ariane, which has guaranteed its independence in the launching of civil and military satellites for almost 30 years and has won a significant part of the highly competitive commercial market. This market provides the Ariane system with the production volume indispensable for its reliability, which also benefits institutional launches. Europe's commercial market share will be even larger if the launch system is flexible and adaptable to the diversity of demand. Probable future technological changes make flexibility more necessary still. Two technical characteristics will be key: a large enough payload capacity and the injection of satellites into energetic orbits, including final geostationary orbit. But carrying out such missions will only be possible if a new generation upper stage is used. The November 2008 ESA ministerial meeting opted to wait until 2011 to decide whether this is necessary, making it doubtful whether Arianespace will be able to maintain leadership in the commercial market. The authors urge a rethink of this position.  相似文献   

7.
Miller RH 《Acta Astronautica》1995,36(8-12):581-587
Human productivity during assembly operations in-orbit is dependent on limits set by fatigue, metabolic rates, learning, and assembly techniques. In order to quantify these effects, tests were conducted in the NASA MSFC Neutral Buoyancy Simulator, in the NASA KC-135 in parabolic flight, and in space with the EASE program during the Shuttle Atlantis mission 61-B. A separate program attempted to relate productivity to system costs. Because of the surprisingly high productivity which had been demonstrated in orbit, it was shown that assembly operations would have only a small effect on system costs at the present level of launch costs. The results of these continuing studies have been reported in a recent paper(1). They will be briefly summarized here and the results updated to include additional cost elements and to examine the effects of reductions in transportation costs, resulting from advances in technology and from increased demand, on system costs. It is shown that, as launch costs are reduced, the assembly costs could become an increasingly important component of the total system costs.  相似文献   

8.
Recent advances in materials technology have improved the performance capabilities of inflatable, flexible composite structures, which have increased their potential for use in numerous space applications. Space suits, which are comprised of flexible composite components, are a good example of the successful use of inflatable composite structures in space. Space suits employ inflatables technology to provide a stand alone spacecraft for astronauts during extra-vehicular activity. A natural extension of this application of inflatables technology is in orbital or planetary habitat structures. NASA Johnson Space Center (JSC) is currently investigating flexible composite structures deployed via inflation for use as habitats, transfer vehicles and depots for continued exploration of the Moon and Mars.

Inflatable composite structures are being investigated because they offer significant benefits over conventional structures for aerospace applications. Inflatable structures are flexible and can be packaged in smaller and more complex shaped volumes, which result in the selection of smaller launch vehicles which dramatically reduce launch costs. Inflatable composite structures are typically manufactured from materials that have higher strength to weight ratios than conventional systems and are therefore lower in mass. Mass reductions are further realized because of the tailorability of inflatable composite structures, which allow the strength of the system to be concentrated where needed. Flexible composite structures also tend to be more damage tolerant due to their “forgiveness” as compared to rigid mechanical systems. In addition, inflatables have consistently proven to be lower in both development and manufacturing costs.

Several inflatable habitat development programs are discussed with their increasing maturation toward use on a flight mission. Selected development programs being discussed include several NASA Langley Research Center habitat programs that were conducted in the 1960s, the Lawrence Livermore National Laboratory inflatable space station study, the NASA JSC deployable inflatable Lunar habitat study, and the inflatable Mars TransHab study and test program currently ongoing at NASA JSC. Relevant technology developments made by ILC Dover are also presented.  相似文献   


9.
In 2009 President Obama proposed a budget for the National Aeronautics and Space Administration (NASA) that canceled the Constellation program and included the development of commercial crew transportation systems into low Earth orbit. This significant move to shift human spaceflight into the private sector sparked political debate, but much of the discourse has focused on impacts to “safety.” Although no one disputes the importance of keeping astronauts safe, strategies for defining safety reveal contrasting visions for the space program and opposing values regarding the privatization of U.S. space exploration. In other words, the debate over commercial control has largely become encoded in arguments over safety. Specifically, proponents of using commercial options for transporting astronauts to the International Space Station (ISS) argue that commercial vehicles would be safe for astronauts, while proponents of NASA control argue that commercial vehicles would be unsafe, or at least not as safe as NASA vehicles. The cost of the spaceflight program, the technical requirements for designing a vehicle, the track record of the launch vehicle, and the experience of the launch provider are all incorporated into what defines safety in human spaceflight. This paper analyzes these contested criteria through conceptual lenses provided by fields of science and technology policy (STP) and science, technology, and society (STS). We ultimately contend that these differences in definition result not merely from ambiguous understandings of safety, but from intentional and strategic choices guided by normative positions on the commercialization of human spaceflight. The debate over safety is better considered a proxy debate for the partisan preferences embedded within the dispute over public or private spaceflight.  相似文献   

10.
Robert A. Goehlich   《Space Policy》2005,21(4):293-306
It is important for any new launch system to develop a successful pricing strategy and to optimize launch system parameters to receive a high economic profit. A question arises, what will happen when an existing suborbital flight market (the first likely to be established in space) is interfered with by a new established orbital flight market for space tourism. There is a risk that the suborbital space tourism market could be almost instantly displaced when a product capable of reaching orbit was introduced. This is best discussed using the following three cases whose results are presented in this paper. Case A presents a ticket pricing strategy for a suborbital and orbital vehicle if the two vehicles do not compete in the same market. Case B shows the necessary ticket pricing strategy for a suborbital vehicle if there is competition from an orbital flight operator. However, the suborbital vehicle would not be able to keep up with a drop in ticket prices due to its obsolete characteristics. Thus, the suborbital vehicle would be forced to stop operation in the year when flight costs became higher than flight receipts as shown in case C.  相似文献   

11.
Space is now a global business, yet the cost of getting to space is still high. Developing new launch vehicles that are cheaper, safer, and more reliable is the key to both rapid commercial growth and to more and better government uses of space. However, the R&D process leading to new launch vehicles is expensive and technically challenging; the past 50 years have seen many government development programs, but no major technological breakthroughs. Perhaps, it is therefore time to think about other ways of developing new launch vehicles. The best expertise in this field resides primarily with private companies and is spread across many actors and nations. A consortium led by space firms might be a better approach to opening up space in the 21st century. Governments will have to develop new policies treating space as though it were a commercial industry, in particular, relaxing export trade restrictions wherever possible. Issues of dual-use may be outweighed by the rapidly growing widespread availability of launch capabilities. Since new launch vehicles will require large up-front R&D expenditures, government support will continue to be needed to supplement private capital funds. Contributions to this effort should be international. However, difficult it might be in today's security conscious environment to reorient government policy, doing so may offer the most efficient and successful way to break the technological and economic barriers to more reliable access to space.  相似文献   

12.
空间短时飞行试验是指以探空火箭、气球、亚轨道重复发射工具等为主要实现手段,将待试验对象发射到一定高度,进行科学实验和技术验证的研究方法。对空间短时飞行试验工具的发展历史和应用现状进行综述,对探空火箭、气球、亚轨道重复发射工具在科学观测、新技术试验中发挥的作用进行总结和概括,以NASA飞行机会计划FOP为例,对其在有效载荷技术成熟度评估中的应用情况进行了重点阐述,结合我国空间科学探测和空间技术试验的迫切需求,对空间短时飞行试验工具在我国的应用前景进行了展望和预测。  相似文献   

13.
NASA has created a plan to implement the Flexible Path strategy, which utilizes a heavy lift launch vehicle to deliver crew and cargo to orbit. In this plan, NASA would develop much of the transportation architecture (launch vehicle, crew capsule, and in-space propulsion), leaving the other in-space elements open to commercial and international partnerships. This paper presents a space exploration strategy that reverses that philosophy, where commercial and international launch vehicles provide launch services. Utilizing a propellant depot to aggregate propellant on orbit, smaller launch vehicles are capable of delivering all of the mass necessary for space exploration. This strategy has benefits to the architecture in terms of cost, schedule, and reliability.  相似文献   

14.
The technical development trend of future launch vehicle systems is towards fully reusable systems, in order to reduce space transportation cost. However, different types of launch vehicles are feasible, as there are
• —winged two-stage systems (WTS)
• —ballistic single-stage vehicles (BSS)
• —ballistic two-stage vehicles (BTS)
The performance of those systems is compared according to the present state of the art as well as the development cost, based on the “TRANSCOST-Model”. The development costs are shown versus launch mass (GLOW) and pay-load for the three types of reusable systems mentioned above.It is shown that performance optimization and cost minimization lead to different results. It is more economic to increase the vehicle size for achieving higher performance, instead of increasing technical complexity.Finally it is described that due to the essentially lower launch cost of reusable vehicles it will be feasible to recover the development cost by an amortization charge on the launch cost. This possibility, however, would allow commercial funding of future launch vehicle developments.  相似文献   

15.
Informed maintenance for next generation reusable launch systems   总被引:1,自引:0,他引:1  
Perhaps the most substantial single obstacle to progress of space exploration and utilization of space for human benefit is the safety & reliability and the inherent cost of launching to, and returning from, space. The primary influence in the high costs of current launch systems (the same is true for commercial and military aircraft and most other reusable systems) is the operations, maintenance and infrastructure portion of the program's total life cycle costs. Reusable Launch Vehicle (RLV) maintenance and design have traditionally been two separate engineering disciplines with often conflicting objectives - maximizing ease of maintenance versus optimizing performance, size and cost. Testability analysis, an element of Informed Maintenance (IM), has been an ad hoc, manual effort, in which maintenance engineers attempt to identify an efficient method of troubleshooting for the given product, with little or no control over product design. Therefore, testability deficiencies in the design cannot be rectified. It is now widely recognized that IM must be engineered into the product at the design stage itself, so that an optimal compromise is achieved between system maintainability and performance.The elements of IM include testability analysis, diagnostics/prognostics, automated maintenance scheduling, automated logistics coordination, paperless documentation and data mining. IM derives its heritage from complimentary NASA science, space and aeronautic enterprises such as the on-board autonomous Remote Agent Architecture recently flown on NASA's Deep Space 1 Probe as well as commercial industries that employ quick turnaround operations. Commercial technologies and processes supporting NASA's IM initiatives include condition based maintenance technologies from Boeing's Commercial 777 Aircraft and Lockheed-Martin's F-22 Fighter, automotive computer diagnostics and autonomous controllers that enable 100,000 mile maintenance free operations, and locomotive monitoring system software.This paper will summarize NASA's long-term strategy, development, and implementation plans for Informed Maintenance for next generation RLVs. This will be done through a convergence into a single IM vision the work being performed throughout NASA, industry and academia. Additionally, a current status of IM development throughout NASA programs such as the Space Shuttle, X-33, X-34 and X-37 will be provided and will conclude with an overview of near-term work that is being initiated in FY00 to support NASA's 2nd Generation Reusable Launch Vehicle Program.  相似文献   

16.
介绍一个新的化学火箭推进领域--低温固体推进技术,叙述了这种新一代固体火箭发动机的基本原理、结构形式、特点和有关技术问题,近年来国外研究工作取得的进展及应用于航天运载火箭的潜力。  相似文献   

17.
统计了近10年来欧洲、日本、美国的固体运载火箭发射情况,系统分析了这些火箭使用的固体发动机性能参数,梳理了其发展脉络。这些国家和地区固体运载火箭主动力系统低成本的技术思路、模块化的发展方向、自动化的生产条件、完备的寿命评估体系,能够为我国运载火箭固体动力系统现阶段的使用、改进,以及未来的发展、规划提供参考和借鉴。  相似文献   

18.
The feasibility of building commercial spaceports is being actively investigated in several countries. Potential benefits include boosting economic development and assisting the commercial launch industry. This report finds, however, that commercial spaceport development will probably not be capable of generating a large enough return on investment to attract private sector involvement without significant government assistance. It is also unlikely that the market for large launch vehicles will support spaceport development; however, small satellites may offer better prospects.  相似文献   

19.
After a proposition from Russia to France, ESA agreed to see Soyuz rockets take off from French Guiana. From industry, to governments and agencies, many Russian and European actors were involved in this project and they all had different motives. It is therefore relevant to try to discern them so as to understand the rationale behind this cooperative endeavor. Soyuz's primary role is to consolidate Arianespace commercial position in the launching market and to bring activity and founding to a stagnating Russian space sector. With this decision Arianespace will have a full range of commercially available launchers with Soyuz completing the two European rockets Vega and Ariane V. But since Vega and Ariane must have the priority, there is a risk to see an insufficient launch rate for Soyuz, which would not satisfy the Russian partners. Commercial elements alone cannot justify the agreement. There is a larger strategic ambition behind. What is at stake is the future development of innovative launch systems. It is important for ESA to maintain an autonomous access to space and to maintain a dynamic and strong European propulsion industry. Cooperation with Russia can offer an increase of expandable rockets capabilities and can pave for the next generation of launch vehicles. Moreover, we can detect an interest in acquiring a system that has the potential for human space flight capacity. Finally, the decision to launch Soyuz from French Guiana was the conjunction of Russian and French national interests, which led to a complete redefinition of the relations between Europe and Russia. It is of strategic importance that we, Europeans, adapt to this evolution and understand the new place that Russia takes in our space sector.  相似文献   

20.
Eurospace 《Space Policy》1994,10(4):322-326
This is an edited part of a report by the European consortium Eurospace on the potential for the continent of small missions. A growing feature of the space market for communications, Earth observations and science and technology development, they represent both a threat of missing an important future market and an opportunity to develop a new capability offering better value for money and increasing the effectiveness of European space endeavours. A new pump-priming programme, the European Small Space Missions Initiative (ESSMI), is put forward to avoid the present vicious circle in which small missions are not proposed because of the lack of launch opportunities and launch vehicles are not developed because of lack of demand.  相似文献   

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