Constructively growing the sounding program: A technology development line of sounding rocket launches

Executive Summary: The rocket program has benefitted from recent funding increases that have helped to stabilize it. However, there are continuing, varied, and consistent programmatic and political reasons to continue to grow the program, as listed in the NRC Suborbital report. These include both long-term technological development needs, frequent access to space needs, and personnel development needs, both involving science students and NASA engineering staff. We propose that a competitive line of sounding rocket launches be added to the existing scientifically-competed program. This new line would be dedicated to technology development, enabling sounding rocket missions with long-term science goals but not necessarily immediate science closure.

The Problem of Limited Opportunities to Launch New Payloads Since its inception, a major goal of the NASA sounding rocket program has been to facilitate low-cost rapid turnaround development of innovative new sensors, instruments, and mission concepts for space flight. Many of the nation’s current generation of senior space scientists established their careers through instruments flown on sounding while they were graduate students. Indeed, as noted in the 2010 report to the National Research Council by their “Committee on NASA’s Suborbital Research Capabilities”, the sounding rocket program has historically been “a vibrant and productive source of seed corn for NASA technology, science, and engineering talent.”

Yet the section of this same report that summarizes the current status of this program is titled “Erosion of a National Asset”. The general picture presented is that of a critical and once vibrant program that has in recent years been afflicted by steady decline. To quote from the report “According to the SRPO and NASA Headquarters, the average flight rate over the last 10 years was 17 core science and 5 reimbursable flights per year (22 total flights) with a total of 2 field campaigns in the entire period. In the years prior to that decade, the average flight rate was 28 flights per year and there were yearly remote campaigns.” Considering that the reimbursable missions are not core science, the current rate of science missions is effectively 60% of what it was just 10 years ago.

The rocket program has benefitted from recent funding increases that have helped to stabilize it. However, there are continuing, varied, and consistent programmatic and political reasons to continue to grow the program, as listed in the NRC Suborbital report. These include both long-term technological development needs, frequent access to space needs, and personnel development needs, both involving science students and NASA engineering staff. The immediate scientific return of the sounding program is likely to scale roughly in proportion to the number of missions flown. However, the decline noted above will likely induce a number of “multiplier” effects, such that the overall impact on the long term future of the nation’s space science program is likely far more severe than a simple linear downscaling. These multiplier effects arise for a number of reasons, including:

 Fewer new sensors, instruments, and mission types can be developed;  The relative scarcity of launches means that the success of each one is much more important, which stifles innovative or potentially higher risk missions;  It is much harder to attract and train students to work on developing new flight hardware, because the chances are so low that they’d ever get to see their instruments flown;  Research groups that currently are the main repositories of expertise in this area may close down as a result of their inability to maintain consistent viable funding.

Reinvigorating NASA’s Suborbital Space Science Program We propose that the most immediate way to reinvigorate suborbital space science is to target the “multiplier” effects mentioned above. We suggest that in addition to the science focus of the rocket program, which we consider vitally important, NASA should invest heavily in the short term on development of new and innovative mission technologies. Such a new technology development effort will provide the community with a new “toolbox” of tested and flight-hardened instruments and observation concepts to apply to their science questions, while at the same time injecting a cohort of new students, post- docs, and field-trained engineers into the field. A return to nearly 30 flights per year distributed roughly between core science and technology development constructively grow the program, and greatly facilitate scientific advancement and the development of new ideas, approaches, and people.

Three program thrusts are suggested to reinvigorate technology development. First, a substantial expansion is suggested for the existing SR&T programs, to enable development of new sensor concepts and technologies, and to test them under ground based laboratory conditions. These programs have not been substantially funded in recent years, but an increase now would facilitate the rapid development of instruments that could be used on sounding rockets. There is an existing program element specifically for this purpose, with established systems for proposal review, award management, and reporting of results.

In parallel with this, a new and separate initiative is suggested with the specific purpose to dramatically increase the sub-orbital launch opportunities available for testing and demonstrating newly developed technologies under flight conditions. The hallmarks of this proposed program would be fast turnaround, the fostering of innovation and its associated risk, and a culture that did not automatically penalize failures. Rather, failures that were understood and remediated would be seen as healthy and desirable outcomes of this flight testing program. Graduate and undergraduate student participation should be strongly encouraged, and internships by NASA engineering staff could be explored. This fostering of innovation would be applied to the efforts of both the science teams bringing new instruments forward for test flights, and to the contractors tasked with executing these missions.

This initiative could entail new mission development models at WFF/SRPO. One suggestion is that NASA emphasizes the development and dissemination of commonly used experiment components. Currently there is little sharing of designs among experimenters. If NASA assumed the role of maintaining a data base of commonly used experiment hardware that all teams could access, then some of the design time, and therefore development time and cost, could be reduced. A set of standards, such as are used in CubeSat development, could also be developed. These would be available to all experimenters and used to the extent that they facilitate the development process. These designs and standards are not forced on the experiments as it is crucial that the program be flexible and encourage innovation.

Another possible component of this initiative for increased launch opportunities would be for one of the existing launch ranges to host an annual campaign during which several complete sounding rockets would be tested, integrated and launched – with each vehicle carrying multiple payloads under test. These campaigns would be intensive “space camp” style activities during which multiple experiment teams would work in parallel both on their own payloads, as well as hopefully helping each other out to bring the completed vehicle packages to the launch rail. Students would be involved and would benefit greatly from such collaboration. Cost and development times would be reduced.

Various mechanisms can be imagined for how best to implement a line of competed launches dedicated to technology development. The most important element, though, would be a growth of the program sufficient to allow a significant increase in the number of competed launches, by inaugurating a new program dedicated to the long-term goals of technology development. Community discussion will provide input on how these initiatives should be applied. However it is implemented, such a program would provide benefits to the community through increased opportunities for student development, for engineering personnel development, and for science through high-level opportunities for technology development.

The third thrust is aimed at filling the logarithmic gap between sounding rockets (~$2M) and explorers (~$200M). A recent study conducted by the NASA (WFF), commissioned by the NASA astrophysics sounding rocket assessment team (ASRAT), showed how advances in commercial launch technology could be used to establish an Orbital Sounding Rocket (OSR) program that would provide extended duration sounding rocket flights of 1 - 30 days. The OSR program would be managed and operated by the NASA Wallops Flight Facility (WFF), whose low-cost, risk- tolerant culture is ideally suited to this effort. The OSR program is analogous to the highly successful Long Duration Balloon Program, in which the community uses balloons to perform breakthrough science. OSR payloads will be competitively chosen from successful sounding rocket experiments based on scientific and implementation merit. The goal is ~ 1 flight/year for 1000 lb payloads. This program would also provide routine opportunities for small (1-100lb) secondary payloads. The OSR cost, based on a preliminary WFF study is $15M/flight, including payload modification, test and integration, procurement and processing, launch and mission operations. A launch vehicle, for example the SpaceX Falcon 1, could deliver a previously proven sounding rocket payload to orbit for several days, which would provide much more that a factor of 1000 improvement in science return in comparison to 400 seconds typically available with today's sounding rockets. Such frequent access would allow the pursuit of high-risk high-value science, be and innovative approaches, and rekindle the competitive spirit of the early years.

References Committee on NASA's Suborbital Research Capabilities; National Research Council (2010), “Revitalizing NASA's Suborbital Program: Advancing Science, Driving Innovation, and Developing a Workforce”, The National Academies Press, ISBN-10: 0- 309-15083-3 or online at http://www.nap.edu/catalog.php?record_id=12862.

Astro2010: The Astronomy and Astrophysics Decadal Survey, Position Papers, no. 36 (2009), "Reinvigorating the Astrophysics Sounding Rocket Program: Strategic Investment in the Future of Space Astronomy" http://sites.nationalacademies.org/BPA/BPA_049492