E N G I N E E R I N G & T E C H N O L O G Y
Sizing Up NASA
The failure of several recent space missions, including the Mars Polar Lander, has brought NASA’s strategy for managing its projects under intense scrutiny. Designed to cut costs from as much as $1 billion to around $150 million per mission, this strategy — dubbed the agency’s “faster, better, cheaper” approach — relies on using smaller project teams and incorporating off-the-shelf technologies that have already been tested and proven.
This streamlining approach has succeeded in spawning more-efficient management techniques and has created ways to infuse state-of-the-art technology more rapidly into the agency’s projects, acknowledges a recent report from a National Research Council committee. However, it cautions that project planning, including determining mission size and cost, should be firmly driven by the mission’s scientific objectives. For instance, instead of looking first to cut costs, NASA should consider factors such as the site to be explored and its physical characteristics as well as the type of data to be collected.
NASA also should look at options for reducing the huge cost of launching space missions, the report urges. It suggests using foreign-launched vehicles, where appropriate, and increasing international collaboration on space missions. Another suggestion is to have NASA announce opportunities for U.S. researchers to propose instruments or contribute in other ways to foreign-led missions. By making these changes, future foreign-led missions could be included in NASA’s overall science and mission-planning efforts. — Bob Ludwig & Kathi McMullin
Assessment of Mission Size Trade-offs for Earth and Space Science Missions. Ad-hoc Committee on the Assessment of Mission Size Trade-offs for Earth and Space Science Missions, Space Studies Board, Commission on Physical Sciences, Mathematics, and Applications (2000, approx. 106 pp.; ISBN 0-309-06976-9; available from National Academy Press, tel. 1-800-624-6242; $25.50 plus $4.50 shipping for single copies).
The committee was chaired by Daniel Baker, director of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. The study was funded by NASA.
Safe Send-offs Into Space
When it comes to the U.S. space program, the private sector is launching more satellites than the program’s traditional participant — the federal government. In 1997 commercial launches — mostly to place communications satellites into orbit around the Earth — for the first time outnumbered government launches at Cape Canaveral in Florida, one of the nation’s two launch ranges. The other range is located at Vandenberg Air Force Base in California.
To remain competitive in the global market, efforts are under way to replace aging rocket launch support systems with modern technologies. The Air Force already plans to implement a new vehicle tracking system based on the Global Positioning System. Further, a new report from a Research Council committee says that using new technologies to improve procedures can increase efficiency and lower costs without compromising safety standards.
As part of its range safety program, the Air Force developed risk standards that all launches must meet. These new standards have been enforced at both ranges since at least 1995. However, range managers continue to use overly cautious procedures and mechanisms that do not contribute to overall safety, the committee said. For example, the process for determining whether a launch vehicle is off-target and its flight must be terminated should be correlated more closely to actual risk.
These standards also are applied differently at each site, which can be costly for users who must reconfigure or retest launch vehicles to meet the requirements. The Air Force should re-evaluate its risk-management process and enforce safety standards that are consistent at both ranges, the report says.
Restricted areas near the ranges protect aircraft and boats from launch hazards. Since air and boat traffic are expected to increase, as is the frequency of launches, the report recommends improving the public communications and notification process. The Air Force Space Command also should employ new, more-effective aircraft equipped with state-of-the-art surveillance and imaging systems, to quickly detect and clear surface and air traffic from restricted areas. And as an incentive for boaters and pilots to comply with safety regulations, the report says the Air Force should work with the U.S. Coast Guard, the Federal Aviation Administration, and the local U.S. Attorney’s office to strengthen prosecution of violators. — B.L.
Streamlining Space Launch Range Safety. Committee on Space Launch Range Safety, Aeronautics and Space Engineering Board, Commission on Engineering and Technical Systems (2000, 70 pp.; ISBN 0-309-06931-9; available from National Academy Press, tel. 1-800-624-6242; $18.00 plus $4.50 shipping for single copies).
The committee was chaired by Robert E. Whitehead, retired associate administrator for aeronautics and space transportation technology at NASA, who new resides in Henrico, N.C. The study was funded by the U.S. Air Force Space Command.
Role of Small Satellites
Historically, NASA and the National Oceanographic and Atmospheric Administration (NOAA) have employed costly large satellites containing sophisticated instruments to observe and collect data on the Earth’s environment, including its weather and climate. A new report from the Research Council examines the technical risks and benefits — and the cost-effectiveness — of distributing the sensors that retrieve these data to a larger number of smaller spacecraft.
The committee that wrote the report found that small satellites — defined as weighing 100 to 500 kilograms — have considerable, but not universal, usefulness in Earth observation programs. For example, the shortened development time that characterizes small satellite programs allows designers to incorporate newer technologies. Distributing sensors on a comparatively large number of smaller spacecraft also allows greater flexibility in the choice of key mission parameters, such as the spacecraft’s orbit. However, the committee found that this did not necessarily lower the overall cost of the mission.
The cost advantages of distributing a particular set of sensors among a larger number of smaller satellites can hinge on a variety of factors, including how a particular satellite is being used, the report says. If an instrument fails on a satellite that is providing the civilian or military community with weather data, for example, it would be necessary to send up another satellite, even if other sensors on the original satellite are still operational.
Smaller satellites should be viewed as a complement, not a replacement, for larger satellites, the committee said. While technological advances have led to miniaturized remote sensors that perform many Earth observation missions, some projects incorporating multiple sensing devices continue to justify a large payload. In addition, some missions simply cannot be performed on smaller satellites because of limits imposed by the basic laws of physics. The report recommends that the spacecraft “architecture” — the mix of small and larger spacecraft and the distribution of sensors — be chosen only after doing a comprehensive trade-off analysis of alternatives. Such an approach would allow for the spacecraft mix to be tailored to the objectives and requirements for a particular mission. — B.L.
The Role of Small Satellites in NASA and NOAA Earth Observation Programs. Committee on Earth Studies, Space Studies Board, Commission on Physical Sciences, Mathematics, and Applications (2000, 104 pp.; ISBN 0-309-06982-3; available from National Academy Press, tel. 1-800-624-6242; $25.25 plus $4.50 shipping for single copies).
The committee was chaired by Mark R. Abbott, professor of biological oceanography, College of Oceanic and Atmospheric Science, Oregon State University, Corvallis. The study was funded by NASA and NOAA.