THEY USED TO SAY that man would never go to the moon, because at the speed of the fastest racehorse, the trip would take years.
Lately, the thinking has changed.In the era of the space shuttle, people smile at accounts from 50 years ago, when the idea of space travel was consigned to the realm of Buck Rogers matinees and white-coated profes sors in mountaintop observatories.
Yet when Brig. Gen. Kenneth E. Staten, program manager for the $4 billion effort to build a plane that can fly up into orbit, suggested that airport managers get ready for hypersonic planes burning liquid hydrogen, he got a reaction only a little more positive than whenColumbus suggested European seamen could reach the Far East by sailing west. Despite raised eyebrows, Gen. Staten predicted that within a quarter of a century, a hypersonic transport will be carrying passengers from San Francisco to Singapore in less than three hours.
Airport executives have reason to be skeptical. The much simpler technology needed to fly at supersonic speeds has existed for more than 20 years, but the United States has yet to build a supersonic transport. Because of noise problems, Concorde SSTs operated by the British and French are required to fly at inefficient subsonic speeds over most land masses and do not call at many of the world's major airports. The Concorde may be operationally profitable, but the plane has not begun to repay its huge development costs.
At the same time, however, writing off the national aerospace plane is as much a mistake as sticking to horseback in an age that builds Saturn V moon rockets.
With so many telephone relay satellites operating that one phone call in three will be routed by way of geosynchronous orbit, we have become a nation that depends on space technology. Banking, shipping, manufacturing and even newspapers cannot function effectively without it. It is so vital in keeping the peace that some analysts have declared that the most hostile action that could be taken against the United States would be destruction of its surveillance and communications satellites. The loss of the Challenger, and the temporary suspension of spaceflights that followed, underscores just how fragile our physical access to that network is.
Contingency plans for protecting the network - the possibility of launching the shuttle or unmanned devices from missile silos in the event of loss of the Kennedy and Vandenberg launch sites - entail extreme difficulties. That's why the Air Force is so concerned about orbit-on-demand - the ability to continue to reach space without being limited to one or two highly vulnerable ground sites. Providing orbit-on-demand is what the national aerospace plane, the X-30, is all about. Using ramjets and lightweight materials that did not exist a decade ago, the experimental aircraft would be able to take off from a conventional airport, reach hypersonic speeds and finally climb out of the atmosphere into space.
Even if a hypersonic plane never carries a single paying passenger, its importance in the development of commercial aviation technology cannot be underestimated.
Perhaps 25 years from now, the average airline passenger will not be riding in an Orient Express plane with the brute power needed to blast into orbit. He may, however, be riding in a plane using technology pioneered by the X-30. That passenger may well be inside an advanced commercial airliner made of ultra-light, ultra-strong plastics, like those on the X-30. While there is little hope that airline food will improve over the years, that passenger may be eating it while traveling at speeds that make the Concorde look slow.
No one is riding around in X-15 rocket planes these days, but few doubt the role the plane played in showing how a high-speed vehicle like today's space shuttle could safely descend from the top of the atmosphere without power.
That's why we believe that the commercial aviation industry will be the ultimate beneficiary of the national aerospace plane. Airport managers might not need to start digging holes for liquid hydrogen tanks just yet, but they should prepare themselves for the changes the plane will inevitably bring about.