To avoid system errors, if Chrome is your preferred browser, please update to the latest version of Chrome (81 or higher) or use an alternative browser.
Click here to login if you're an NAE Member
Recover Your Account Information
Author: Robert S. Walker
Technology development in hypersonics could remap the future.
At the opening session of the Commission of the Future on the United States Aerospace Industry (the Aerospace Commission), I quoted Wilbur Wright who once opined that mankind would not achieve flight "for a thousand years." This was just a year before he and Orville achieved powered flight. So much for predicting the future in aerospace! Wilbur was wrong about their timetable, but, when it comes to technology, it is difficult to predict where you are going based on where you are.
We do know that the history of aeronautics and flight has been a history of progress and success achieved by the integration of technologies that are either coming of age or still in the laboratory. The Wright brothers’ success was based on integration of the internal combustion engine, a rather new technology at the time, with the control of wing surfaces. Prior to the invention of the internal combustion engine, power sources were too heavy for an airplane. Thus, the integration of internal combustion and aeronautics began a century of flight.
Throughout the twentieth century, aviation advancement depended on the continuous adaptation of new technologies into the field. As breakthroughs occurred in propulsion, aerodynamics, and materials, they found their way into new generations of aircraft. Based on what is going on in laboratories today and where technology breakthroughs are aiming, we can make some educated speculations about the future of aviation.
Technology development in hypersonics could remap the future. The U.S. Department of Defense (DOD) has launched the National Aerospace Initiative as part of the Defense Research and Engineering Program. Work on hypersonics will focus on propulsion technologies and new fuels for aviation, such as hydrogen, which has been used extensively as a fuel in the space program but only experimentally in aviation. As scientists work toward the creation of high-speed vehicles, hydrogen could be the fuel of choice. And, of course, hydrogen is also being investigated to meet a variety of other energy needs.
Propulsion technology has not advanced very far in the past half-century. A robust hypersonic program will involve a reappraisal of supersonic ramjet engines (scramjets); in fact, some of our international competitors are already conducting interesting tests in this area. A predictable outcome of a hypersonic program is another look at aerospike engines, which were developed to power the X33. One of the great disappointments in recent aviation history was the failure to flight test the X33 after it was 85 to 90 percent complete. Under pressure from supporters of the space shuttle, the National Aeronautics and Space Administration (NASA) cancelled the program, thus passing up an opportunity to flight test a new generation of engines that had proven to be quite capable in stationary tests.
Hypersonics will also involve advanced aerodynamics. Today, sonic boom creates an environmental and quality-of-life hurdle for high-speed travel. Work is under way on new designs to reduce sonic boom, which would open the way to hypersonic aircraft. Thus, research on hypersonics could lead to new developments in propulsion, materials, fuels, and design. But that may be only the beginning. Information systems, for example, will also be important for the development of new aircraft designs, as well as for avionics and flight control. The air traffic control system of the future will rely upon advanced, space-based information regimes and the capability of spectrum compression.
If we look farther down the road, advanced experimentation in the nation’s laboratories reveals even more exciting possibilities. Work on antimatter being done at Pennsylvania State University and elsewhere could lead to completely new propulsion capabilities in this century. Some scientists also are seriously considering gravity management. Antimatter and gravity management could potentially lead to an aerospace future of unimaginable proportions.
The Aerospace Commission was chartered to consider potentials beyond technological advances. We were also asked to look at the aviation marketplace, with a focus on current developments as a basis for predicting changes in the future. Our conclusions are reflected in the title of our report, Anyone, Anything, Anytime, Anywhere.
We identified one overwhelming desire for military and civil aviation - people want to be moved quickly, exactly where they want to go and when they want to go. Defense planners want to be able to move people and munitions quickly wherever they are needed in an emergency. Commercial aviation aspires to move people and goods to specific destinations in as little time as possible. Aerospace assets are the best way of fulfilling everyone’s dream of anyone, anything, anytime, anywhere.
The global marketplace of the future is going to demand increasing individualization and customization. For the aviation industry, which has relied heavily on mass production and mass movement, the new marketplace will present many challenges. The high-end traveler of the future is not going to be satisfied to be shuffled from hub to hub before getting to his or her final destination. High-end travelers will want to fly directly to their destination at their convenience. Military planners will want the ability to strike almost instantaneously anywhere in the world, and they will need new generations of aircraft with that capability. Technology must be developed to meet the needs of civilian and military aviation.
On the civilian side, the Aerospace Commission focused on the concept of air taxis. A small innovative company, Eclipse Aviation, described its development of reasonably priced jet aircraft designed to become the backbone of an air-taxi service. This concept is consonant with our conclusion that the demand for individualized travel will certainly increase. With air taxis, a businessman or woman would call for service, be picked up at a large or small airport of his or her choosing, and be delivered to the exact destination at the most convenient time. The system would operate on a regional basis at first, for a cost of about one dollar per mile. The need for air-taxi service is already apparent. With the present system, door-to-door flight time on trips of 500 miles or less averages 35 to 80 miles per hour.
Another development likely to have implications for the marketplace is unmanned aircraft, which have already had an impact on military aviation. Unmanned aircraft proved their worth during the conflict in Iraq, but also revealed the need for improvements. An enormous amount of spectrum was required to fly unmanned missions in Iraq. This experience has shown that the widespread adoption of unmanned technology will require more work on spectrum compression and other applications of information technology.
The economics of the marketplace will drive us toward more unmanned capabilities. In the future one can imagine freight being flown largely by unmanned aircraft. Once vehicles and systems are capable of handling planes without pilots, it will make little sense to fly them with pilots.
It may take longer for passengers to fly on pilotless airplanes, but in the course of this century that is also likely. Remember that not too long ago every elevator had a human operator, partly for safety and security. Today we think nothing of putting our safety in the hands of an automatic elevator (except in the Capitol, where elevators still have human operators). Once a safe, secure, robust air traffic management system has been developed, it is not hard to imagine that people will elect to fly aboard pilotless aircraft.
The expanding global economy will also affect the future of aviation. The products we rely upon will no longer be manufactured just down the road or just across the border in a neighboring state. These products will come from all reaches of the globe, as many already do, and as more and more speed of delivery is required, aircraft will become the supply line. In general, the reliance on aircraft to move people, goods, and services around the world will become more pronounced. The global economy will also mean growing competition. Many countries can be expected to make some aspect of aerospace a national priority. We have already seen fiercely competitive commercial operations in space and aviation.
When you look outward, you begin to get a glimpse of a future that may look like this: individualized travel on hypersonic aircraft built of carbon nanotube structures, piloted by nanoprocessors accessing a global guidance network, flying into every locality, powered by antimatter engines, and as accessible to everyone as the transportation system today. This scenario will probably be realized well down the road, but if you think back to the technological growth of the past 100 years, the scenario is well within the realm of possibility. In fact, everything in it is already the subject of laboratory work.
The real question is what policy makers should be doing now. The Aerospace Commission came to the unanimous conclusion that the most important thing is the development of policies that enable us to move toward this exciting future. One priority should be the development of an advanced air traffic management system. The current antiquated system is not capable of handling future demands, and continued dependence on voice communications from ground controllers to aircraft cockpits is untenable. We need to focus on technologies that permit fairly automated, more robust, more secure aircraft control within airspace. Such a system could be adapted from advanced technologies already known to us, which could be accessed without massive cost by using the global satellite constellations being developed by DOD.
The command, control, and navigation satellites under development for military applications could be adapted for civilian use, much the way the global positioning system (GPS) constellation has been adapted to meet civilian objectives. This would greatly reduce the tremendous expense usually associated with the development of an automated air traffic control regime. Even the costs of including civilian components on military spacecraft could be mitigated by interagency cooperation. The nation would acquire a spaced-based system with upgraded ground control elements. The military would fly the space-based hardware, but ground-based operations would be in the hands of the Federal Aviation Administration (FAA). The result would be that the nation would have the advanced air traffic management system necessary for the United States to compete in the global economy and to meet national security requirements.
Since the Aerospace Commission made this recommendation, considerable progress has been made. DOD, the FAA, and NASA have joined a working group to create the system. No doubt, bureaucratic, cultural, and funding issues will have to be resolved, but the first steps are being taken.
Another imperative for the future is a significant improvement in infrastructure beyond air traffic control. One of the most revealing figures we heard was that in the United States commercial flights of 500 miles or less have an average door-to-door speed of 35 to 80 miles per hour. That figure reflects serious problems with infrastructure. Clearly, one way to improve infrastructure is to restructure the airlines. We cannot have a robust aviation system if airlines cannot afford to purchase aircraft, if a significant number of airlines is on the verge of bankruptcy, and if airline business plans do not work because more and more high-end customers, who used to fly in the front of airplanes and pay a substantial portion of the cost, are traveling on charter aircraft. In the future, even more of them will opt to fly by air taxi.
The customers left to airlines are becoming largely vacationers, who want very low prices. Coming up with a profitable business model based on low fares is tricky; at the least, it requires substantial restructuring of old labor agreements. But much more will have to change, including mergers with international airlines and much more customized travel. Aircraft manufacturing will have to be highly productive, thus relying much more on robotics. The military must be able to project power rapidly and decisively using hypersonic weaponry that cuts the time of mission success from hours to minutes. There must be much more interagency planning and policy implementation so that the vast sums of money spent for aerospace are allocated rationally according to broadly determined priorities. Congress must take the "stovepipes" out of the appropriations process so that duplicative spending does not deplete financial resources.
In the future, our export control policy must allow our aerospace industry to compete globally rather than erect barriers to overseas contracts; of course, some technology products must be protected, but the technologies that really do require protection would be more secure if the government were more selective in deciding which products need individual munitions licenses. Government procurement polices must promote growth and the long-term stability of the aerospace industry. Our society must be scientifically and technologically literate, and our educational system must produce the trained workforce we need in aerospace.
Finally, we must invest more in research so that we can achieve breakthrough capabilities and develop new knowledge. In my years on Capitol Hill, I became convinced that the basis for national economic strength and global economic leadership is remaining on the cutting edge of the development of new knowledge. Peoples and nations that are prepared to launch voyages of discovery on earth and in space will dominate this century economically, culturally, politically, and militarily.
Our legacy as a nation in aerospace is to lead, not to follow. The costs of being a follower have been great, so lead we must. Today, our claim to leadership is being challenged on many fronts. The Europeans, Brazilians, and Canadians are on the move in the arena of commercial aircraft. In human space flight, the Chinese have put a man in orbit and announced plans to be on the moon within six years. The Europeans intend to use the Galileo program to leapfrog us in air traffic management. The Russians have tremendous capabilities in robust rocketry.
The Aerospace Commission set forth certain requirements for the United States to retain its leadership in aerospace during this century:
We have been given an opportunity and a challenge - to address the needs, meet the challenges, and move aerospace at least as far forward in this century as our fathers and grandfathers did in the last century. When the Wright brothers gave humans their wings, they extended not only the capability of the human body, but also the capability of the human mind. They extended our vision and our dreams. For some that meant the opportunity to visit distant lands, for others to dream of visiting distant worlds. We are different today than we were 100 years ago because we can fly and because what was once a miracle has become routine. We will be different 100 years from now because humans will populate the heavens. Flight will continue to inspire the imagination. By daring to fly in air and space, we reach to touch the face of creation. When we look up, we see the destiny of mankind and the destiny of America. When we look up, we also look ahead- to a new century of flight.