In his essay “Then and Now in Aerospace” [March 14, page 19] Edward Hujsak makes some excellent and important points. However, far from being at the bottom of the mountain after having reached a peak during Apollo, we are at a well-established base camp on a relatively high plateau thanks to Ed and his many peers among whom I am proud to count myself.
In developing Apollo, we were in new territory with rudimentary tools. Designs then took many minutes of computer time on room-filling machines using proprietary codes developed at great expense or worse were done laboriously on mechanical calculators or slide rules. Today, far more sophisticated and precise design codes run in seconds on desktop or laptop computers and are commercially available to even one-person companies. Three-dimensional self-checking computer models have replaced the many drawing boards of Apollo.
Designs are fed directly to rapid prototype machines or numerically controlled machines. Burt Rutan’s achievements build upon the existing knowledge base in materials, propulsion, aerodynamics and controls. The Delta 4 and RS-68 rocket engine were developed at much lower cost and in much less time than previous new systems because of the sophisticated design and manufacturing capabilities now in place. Aircraft like the 787 are developed with great confidence and minimal redesign. A part of the reason for the smaller number of people in aerospace is actually much greater efficiency and productivity.
Problems that Ed and others like Robert Zubrin have pointed out are in many ways more debilitating to advancements in aerospace.
First there was the lack of clear goals in space exploration allowing NASA to become a rudderless bureaucracy. President Bush has now set visionary goals. However, there remains a lack of political will and enthusiasm to pursue those goals. The natural response to a lack of urgency is to endlessly study alternative approaches.
As Robert Zubrin points out, there are many alternatives to returning to the Moon and then going onto Mars each having advantages and disadvantages. The same was true of Apollo. The selected approach, while succeeding brilliantly did not leave as robust an infrastructure as other methods might have.
What is needed now is the will, enthusiasm and urgency to move to some decision. As all program managers know, any two engineers will have at least two alternate solutions. At some point the program manager must force a decision and move on.
When we stand again on the Moon and put our first footstep on Mars everyone will have regrets that the advantages of approaches not taken were lost. But we will have returned and we will have placed that footprint because we had the courage to make the hard engineering decisions and move ahead. What we still lack is the political will on the part of the people of the country. Once that will is developed, the aerospace industry has the capability to respond.
Stephen A. Evans, Foothill Ranch, Calif.
(Editor’s note: the author is the former director, now retired, of advanced technology programs at Rocketdyne).
