The policies of the agency, including the "faster, better, cheaper" mantra that has dominated NASA for the past decade, have been scrutinized and attacked by a variety of sources, including science journalists, so-called space "authorities" and even members of Congress. Unfortunately, the current public debate between the agency and its detractors has not always been sharply focused on the most important issues raised by the twin failures.
At present, NASA is in dire straits. Its space missions and launch vehicles are failing at an alarming and unacceptable rate. Public confidence in the agency has fallen dangerously low. Support for the expenditure of public monies to accomplish NASA's visionary and worthy objectives continues to erode. Something must be done in the near future, both to reorient NASA, and to reestablish the historical bond between the agency and its constituency, the American people, or there is a non-trivial chance that the nation may ultimately abandon its support of NASA altogether. To preclude this possibility, now would be an excellent time for President Clinton to commission a blue ribbon panel to examine and evaluate every significant aspect of the National Aeronautics and Space Agency, including its objectives, policies and management structure and personnel. As an absolute minimum, it is definitely time to reconsider in detail the processes used by NASA to manage its all-important engineering missions.
Let me say at the outset that I am an unabashed supporter of the exploration of space. It has been my incredible good fortune to have participated, in a significant way, in two of the most exciting and outstanding robotic planetary missions of our epoch -- Viking and Galileo. I have also served as an engineering advisor for dozens of other major NASA missions over the past three decades, including the inexpensive and very successful Lunar Prospector that discovered water on the moon. During this time I have witnessed many changes in the way that NASA conducts its business. In the beginning, I applauded Administrator Dan Goldin's passionate embrace of the "faster, cheaper, better" mantra, for I believed, based on my experience, that considerable cost reductions could be achieved on major engineering missions with no appreciable increase in mission risk. However, in recent years I have been dismayed, and even appalled, at the way that mantra has been invoked as an excuse for sloppy engineering, inept project management and even bad behavior.
"What has gone wrong? Why has the agency whose very name was once synonymous with unparalleled success become the easy target of journalistic cartoons and the butt of so many late night jokes?"
What has gone wrong? Why has the agency whose very name was once synonymous with unparalleled success become the easy target of journalistic cartoons and the butt of so many late night jokes? I believe the answer is straightforward. NASA was originally conceived as an engineering organization. Its early leadership considered engineering excellence to be the sine qua non of the agency's existence. Throughout the organization, management attention was focused primarily on making the correct engineering decision to maximize mission success. Programmatic issues, such as budgetary and schedule ramifications, were always part of the decisions, but these issues were considered to be less important than making certain that the engineering was sound.
Over the years there has been a major paradigmatic shift in the way that NASA projects are managed. Engineering is no longer the primary consideration on agency missions. Programmatics have become the name of the game. Today a project manager at the Jet Propulsion Laboratory or one of the other NASA centers faces an endless sequence of high level reviews of his program's budget and schedule, with significantly less review of the soundness of its engineering design. In such a bureaucratic environment, detailed knowledge of the quarterly costs of each of the major engineering subsystems is a more important attribute for a project manager than a thorough understanding of the strengths and weaknesses of the spacecraft system design.
Under the old NASA paradigm, many projects overran their budgets and some even missed their scheduled launch dates. Why did this happen? In truth, sometimes too little attention was paid to programmatic issues. However, sometimes a project entailed such a high degree of research and development that it was virtually impossible to obtain any kind of accurate cost estimate until the work began. On Viking, for example, the initial estimates of the cost and complexity of a number of its subsystems, including its on-board computer, as well as the critical biology and organic chemistry experiments, were woefully inaccurate. When the engineers on the project finally assessed the technical work that would be necessary to make these crucial elements acceptably reliable, the additional projected costs were quite significant. Nevertheless, NASA management approached the Viking overrun issue from a mission success perspective and eventually agreed to the extra funds. Viking cost more than was planned, but its two Mars landing missions were a smashing success.
Today's projects are forced to stay within their cost and schedule constraints. These constraints are determined very early in the process, long before the details of the mission and spacecraft are well understood. As part of this new paradigm, institutions and project managers are then told, once their project is underway, that if their projected overrun ever exceeds a given value, usually about 10 percent of the total budget, they will be summarily canceled. The net result of this kind of management is easy to predict. The project manager and responsible institution both become highly motivated to avoid cancellation at all costs. Engineering risks that can significantly increase the probability of a mission failure are often accepted, even against the judgment of key technical staff members, simply to maintain a viable project. Although it is rarely said explicitly, the message passed down to the working engineers is that a comparatively high likelihood of mission failure is a less unsatisfactory option than cancellation of the project.
In my personal opinion, this kind of engineering management process is what doomed the Mars Polar Lander. Certainly there were mistakes made during the actual design and implementation of the project, and I feel confident that the Young and Casani teams have adequately identified and prioritized them. But what caused the Polar Lander to fail was no single mistake. It was the process. From the very beginning it was obvious to experienced engineers that the total budget allocated to the complex Mars Polar Lander mission was simply not enough to complete a reasonable engineering design with a high probability of success.
So where should NASA go from here? First and foremost, the agency needs to overhaul its project management processes to make certain that engineering issues are given top priority throughout the design and development cycle. I am not suggesting that programmatic considerations should not be important. Like Dan Goldin, I still believe that many of the future missions, especially those using already existing spacecraft and subsystems, can be implemented for a fraction of what they would have cost under the old style of management. Nevertheless, the agency must realize that for the newer, more complex missions, a process that stresses identification and resolution of key technical issues early in the program is superior to the current method of arbitrarily assigning annual project costs on an a priori basis.
I have two primary suggestions for the individual or group that will undertake the restructuring of the NASA management processes to improve the probability of mission success in the future. First, make certain that all projects include a proper amount of systems engineering. What exactly is systems engineering? It is the effort expended, usually by seasoned engineers, to check, verify and validate that all the individual pieces of the spacecraft or instrument will indeed play together as a unit. A good systems engineer understands the strengths and weaknesses of the entire design and knows, intuitively, what components, tests or analyses are most critical for the success of the mission. Mass, power and margin management; single point failure policies; redundancy design; failure modes and effects analyses; parts selection criteria and test verification matrices are all the province of systems engineering. The systems team is the glue that holds an engineering project together.
In this era of tight NASA project budgets, systems engineering is always a viable candidate for cost reduction. Why? A manager knows his mission cannot function without its science instruments, or a guidance and control system, or a propulsion module. But the benefits of systems engineering are not so tangible. Dropping a set of failure mode analyses or a verification test suite somehow seems more acceptable than removing a science instrument or changing to a cheaper propulsion module with less performance. As an advisor, one of the first questions I always ask is what percentage of the total project budget has been set aside for systems engineering. In my experience, I have found that there is a very strong correlation between missions that have failed and those that have had minimal systems engineering effort.
My second recommendation is that NASA should demand that all major missions have periodic, penetrating and truly independent engineering reviews. The key words in this recommendation that require explanation are "penetrating" and "truly independent". Reviewers should be outstanding, experienced engineers without any connection, in any way, to either the project or the institution that is being reviewed. This review team, which should report to and be compensated by an engineering office at NASA Headquarters, should be chartered to dissect the engineering design of the project, without prejudice, and assess the likelihood of mission success, considering both engineering and programmatic factors. The project should be required to allocate resources for proper support of the reviews, and should be held accountable to give timely answers to all the issues raised by the review team.
Many people believe that the review process described above is standard procedure for current NASA missions. It is not. Yes, putative engineering reviews of major projects are currently held, but they absolutely fail the tests of being either penetrating or truly independent. Too often, other members of the institution that is managing the project conduct these reviews. This produces an obvious conflict of interest. In some cases the project manager himself both chooses and pays for the review team -- a management process that is not likely to yield either a penetrating or an independent review.
A proper, organized engineering review process would pay great dividends to NASA. In the best of all possible worlds, by defending their designs and resource allocations in the presence of challenging peers, project managers would have a heightened awareness of the potential weaknesses in their project plans. Assuming that the review team members were carefully selected and motivated, the process would also induce a cross-fertilization process in NASA that is currently absent and would benefit the entire agency.
The Mars mission failures have again focused public attention on NASA. The agency must seize this opportunity to reconsider its entire way of doing business or it may lose its support from the nation. As a critical first step in this reconsideration, it's time for a thoughtful overhaul of the way NASA manages its flight projects -- an overhaul that should give engineering issues top priority again within the agency.
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