 Welcome to this edition of NASA Images, I'm Lynn Bondrant. During this show, we'll be focusing on historic NASA footage of airplane work. We'll see many tests, including crash tests. Let's go back to 1974 to the NASA Langley Research Center in Virginia for that. Although the safety record of light aircraft continues to improve, there still were 700 crashes in the U.S. last year, resulting in more than 1,300 fatalities. Until now, there has been no reliable method of predicting the behavior of general aviation planes when they do crash. In a joint project with the FAA, NASA is beginning a light aircraft crash safety program at the Langley Research Center in Virginia. This is one of 20 flood damaged planes that will be tested. The actual facility was originally used by Apollo astronauts to practice landing on the moon. The 240-foot-high by 400-foot-long lunar landing practice area is now laced with cables, which are attached to the highly instrumented aircraft before it comes crashing to the ground. Dummy's riding in the passenger seats are instrumented to measure G-forces. Engineers hope to learn what happens to an airframe structure when it impacts and to develop an analytical design tool that can be turned over to the designers and builders of general aviation planes. For this first check-out test, the plane is complete except for tail section and engines. Comparable weights take the place of missing parts, and the fuel tanks are filled with water for weight and balance. This first crash was made at an impact speed of 30 miles per hour. Future drops will be at speeds up to 60 miles per hour. Here you can see some of the resulting damage, most of which was confined to the nose and underside of the aircraft. Describing the program that will follow this series of crash tests, Langley engineer Bob Thompson. In the future, what we hope to learn is to integrate some energy absorption concepts into airframe design technology. This gives the aircraft designer some means of putting together the energy absorption concepts with the airframe. Crash worthiness tests like these may one day lead to the design of lightweight aircraft that can absorb much of the impact energy of a crash and hopefully reduce fatalities. In 1975, NASA Langley engineers are crash testing helicopters. It's on purpose at NASA's Langley Research Center in Virginia. In this case, a 22,000-pound Army helicopter. The big CH-47 helicopter had earlier been damaged by fire at the plant where it was manufactured, making it a good candidate for the crash-worthiness test. Watch again, this time in slow motion because the helicopter is dropped 50 feet to the concrete below. The highly instrumented craft is being used in a cooperative test experiment with the U.S. Army to improve design and safety features of future helicopters. Crash worthiness tests giving aircraft designers important structural information before they go to the drawing boards. One of the possible problems with which pilots must deal when landing planes is wake turbulence or vortices of air which trails planes. These model airplanes have something in common with these Rio planes. They are all part of a NASA research program to learn more about vortices, tornado-like patterns of air that trail behind the wings of airplanes causing varying degrees of turbulence. Dave Scott, Acting Director of NASA's Flight Research Center in California, explains. The vortices are dangerous because these bundles of energy as they follow behind the aircraft leaving awake have the capability of turning over smaller aircraft as they approach a landing. And because of this we have a great deal of concern that many accidents can be caused by the vortices or these bundles of energy as they attempt to turn over an aircraft. While all aircraft cause vortices, large heavy jets such as the 747 and DC-10 create the more serious problems. Air traffic density around major airports adds to the severity of the problem. Because of the many aircraft coming in for a landing in the need to sequence one plane behind the other, aircraft are routinely separated at safe distances to avoid the trailing vortex problem. However, this often results in increased fuel use and traffic delays. Smoke generators mounted on the wings of these planes by NASA researchers make it possible to see and investigate the whirling air patterns. The research has shown that by adjusting wing flaps at different angles and by making various design changes, the intensity of the vortices can be substantially reduced. This kind of aeronautical research today may very well result in even safer, more convenient flights in the future. For our next clip made in 1974, let's go to California where aerodynamic truck tests were made in an effort to reduce fuel use. They come in all sizes, these movers of everything from lettuce to steel. Their box-like shapes allow the packing of high-volume loads. It's believed that both trucks and recreational vehicles like this can be made more economical to operate. In the past, as trucks were manufactured larger and larger, engine size was increased to handle the heavier loads. Now with the continuing fuel problems, engineers are attempting to make the big trucks more efficient. In a joint effort, NASA and the Department of Transportation are in the midst of a research program to do just that. The tests are being done at NASA's Flight Research Center near the Mojave Desert in California on an auxiliary runway. Project engineer Ed Sultzman explains. The experience and background that we have here at the NASA Flight Research Center that bears on tests such as this goes back to the aerodynamics experiments that we've done on various aircraft. And really the means of achieving aerodynamic efficiency on aircraft isn't that different than it is on automobiles and trucks, excepting, of course, on trucks and automobiles you're working at lower speed. Starting with a small delivery van, Ed Sultzman and his team of engineers reshape the vehicle with sheet metal. The test truck has evolved from a square box to its present shape with rounded corners. The major emphasis has been on the elimination of drag, wind resistance that forces the engine to work harder. The method used to define drag is known as the coast down method. After accelerating the truck to 65 miles per hour, the gears are disengaged and the truck is allowed to coast. The deceleration is monitored closely because the time it takes to slow down can be directly converted into drag. So far aerodynamic drag has been decreased a little over 50%. The thing that we're all interested in, of course, is the savings in fuel, the miles per gallon that we can achieve rather than the aerodynamic drag, per se. And the aerodynamic improvements that we've experienced so far are translatable into fuel savings at cruise conditions when you're going down the highway at highway speed, somewhere in the neighborhood of all 15%, perhaps 20% savings in fuel. Other secondary benefits include less pollution and increased engine life. This big tractor trailer, typical of many on U.S. highways, is also being studied. Here engineers attach one of many add-on devices that will modify airflow around the truck and hopefully reduce drag. To help them visualize the flow of air patterns, six-inch long strings or tufts are attached and photographed. These have been used in aeronautical research for years. Another method involves pumping a powder-like substance over the truck as it travels along. A large tractor trailer program has just begun and it's too soon to predict how much fuel might be saved as a result of the truck modifications. A fuel savings of as little as 5%, however, would save thousands of barrels of fuel every day. The researchers are hopeful as they continue to apply aerodynamic techniques to help solve a ground transportation problem. Let's go back into the air for our next clip from 1976. The clip explains that the first day in NASA is for aeronautics. The clip ties together several of the ideas from other films used in the show. For 60 years, NASA has been pioneering in aeronautical research. During World War II, the need was for real-time problem-solving and responding to a variety of crises associated with American bomber and fighter planes. Today, research is aimed at making planes fly higher, faster, farther, quieter, and with greater safety. Consider the problem of wake vortices, invisible tornado-like patterns of air that trail behind large jets causing dangerously turbulent conditions for smaller planes following in their wake. The turbulence is so severe that flight controllers must carefully space takeoffs and landings to avoid them. Research on wake vortices has ranged from studies like these at NASA's Flight Research Center in California, where different combinations of gear and flaps are used to break up the vortex, to an experimental laser system at the Marshall Space Flight Center in Huntsville, Alabama. Working with the FAA, the experimental laser program is an effort to develop an accurate wake vortex detection and monitoring system that would permit tracking the path of the vortices produced by large aircraft. Steel-tested at the John F. Kennedy International Airport in New York, the laser research may one day help make commercial air traffic safer. Information gained by flights of the 2,000 mile-per-hour YF-12 will help the designers of new aircraft and spacecraft. Heating, stability and control, aircraft loads, these are just a few of the many tests underway, using the high-speed planes as flying research tools. The rocket-powered X-24B has completed 36 missions over the California desert near the Flight Research Center, bringing to a close experimental rocket-powered flight tests that began with the XS-1 in 1946. These unique planes have proved extremely valuable in advanced aeronautical research. Using the same aeronautical know-how used to design sleek high-speed jet planes, NASA engineers are cooperating with the Department of Transportation to test a variety of fuel-saving modifications for large trucks. Even the simple changes have provided a 40% reduction in aerodynamic drag, wind resistance that forces the truck engine to work harder. This translates directly into a highway cruise fuel reduction of 20 to 25%. An interesting ground transportation problem being aided by aeronautical research techniques. At the Langley Research Center in Hampton, Virginia, they're crashing airplanes on purpose. Engineers hope that these crash-worthiness tests will help designers build lightweight aircraft that can absorb much of the impact energy of a crash, reducing injuries and fatalities. This is a pilot's eye view coming in for a landing, but there's an easier, less expensive way to fly. It's called the Flight Simulator for Advanced Aircraft. What the pilot sees and hears in this simulator at NASA's Ames Research Center is like the real thing. Another advanced research tool for designing and evaluating aircraft performance without ever leaving the ground. First A in NASA stands for aeronautics. Research aimed at improving the quality and safety of flying. Our next clip from 1976 shows an unusual scissor-like plane design. The scene is an arid lakebed at NASA's Dryden Flight Research Center near the Mojave Desert in California. It's early morning. Engineers and technicians have been here since before sunup. Check out and preparations for the upcoming flight test are painstaking and deliberate. This is not an ordinary plane. It has a scissor-like design that could prove to be the shape of aircraft to come. Studies indicate that if the design features of the oblique wing, as this 25-foot model is called, were applied to full-sized jets, it would allow them to travel faster than sound without leaving the usual sonic boom in their wake and give them increased fuel economy. Before the oblique wing plane takes off, a television-equipped aircraft sweeps over and scans the flight path. What the camera sees will aid this man, the pilot of the oblique wing model. He actually flies the plane from inside this van. Another television camera mounted in the nose of the test aircraft lets him see where the plane's going. Watch now as the ground crews start the engine and launch the oblique wing plane. Crews carefully record how the aircraft responds to a variety of maneuvers. They compare these responses with wind tunnel predictions to better understand what the aircraft is doing and why it's doing it. As you can see, the wing on the aircraft is at an angle to the fuselage such that the left wing points forward of the aircraft. The normal airplanes, the wings are at right angle to the fuselage. On this aircraft, the wing is at an oblique angle such that the left wing points forward and the right wing points aft, and this feature allows the aircraft to have much lower transonic drag than a conventional aircraft. For a transonic airplane designed to use this wing, you would fly at 100 to 200 miles an hour with the wing at zero degrees of yaw. As the speed increases, the wing yaw is increased. Research has shown that oblique winged aircraft compared to fixed wing planes use less fuel and can reduce sonic boom levels. The plane's designer, R.T. Jones, says that using the oblique wing takes maximum advantage of wing sweep in a way that fools the wind by making it think you're going slower than you actually are. The next phase of research could include a 1,500-pound plane with a 30-foot wingspan powered by jet engines. It would have a pilot on board. These artist concepts show how the oblique wing design might be applied to transport type aircraft. The wing, of course, would swing back to a more conventional position for landing. The oblique wing, a unique design that may one day allow planes to fly faster, quieter, and use less fuel. Space engineers have even tested plane designs underwater as we see in this 1977 report from the NASA Dryden Flight Center, California. Ever see a jet plane fly underwater? Well, this model of a 747 almost does just that. But consider first what led to these interesting underwater studies. NASA researchers are trying to solve the problem of wake vortices. Those funnel-like patterns of air that swirl off the wings of planes as they speed along. The larger the plane, the larger the vortex and resulting problem. Vortices can't be seen unless smoke or dipods are attached to the wings. Here the second test plane intentionally follows much closer than normal. This allows engineers to visually observe and study both the vortex and its results. Come all together by carefully spacing takeoffs and landings. If the vortices can be reduced or eliminated, however, it will cut down air traffic delays at many of our busy airports. This is hydronautics in Laurel, Maryland. It was here that NASA recently completed a series of tests to look at the vortex problem from a different angle, underwater. The tank used is 425 feet long, 25 feet wide, and 12 feet deep. Testing an aircraft in water might seem like a strange idea, but water and air are both fluid mediums and the advantage of using water in this case is that you can simulate a Reynolds number much closer to the Reynolds number that you use in flight. And Reynolds number is one of the correlations that you do, one of the ways that you get the scale effects from model testing to flight testing. The vortex generating model is mounted on the carriage and this motor driven carriage moves the model through the water channel. The following model, the small business jet, is mounted on a separate carriage downstream of the generating aircraft. And the test lasts approximately 25 seconds and you get maybe 15 seconds of data from this test run, where the two models are moving on separate carriages through the water towing facilities. As the test progresses, dye is let out of the wingtips of the generator aircraft and this dye will swirl up in the vortex, the axial velocity, so that you can actually see the vortex in the film that we take of the test. Tests of the wake vortices research are encouraging. While NASA is having success in changing air flow over the wings using flaps and deflectors to break up the vortices, the FAA is working to develop instruments to detect and thus avoid them. All part of a continuing effort to improve the safety and comfort of air travel. Our final historic clip is called From Kites to Wings, the year is 1975. Many sports enthusiasts around the world call it hang gliding. 63-year-old aeronautical engineer Francis M. Rogalo, now retired from NASA's Langley Research Center in Hampton, Virginia, he and his wife Gertrude, who co-invented the wing, live in Kitty Hawk, North Carolina. Rogalo enjoys flying a couple of times a week from what's been called the highest sand dune on the east coast, Jockey Ridge. Turn to the left and come down. With a hang glider, as with other aircraft, you have freedom of up and down direction as well as the others. And just getting your feet off the ground and being lifted by the air is a new experience. Before Rogalo, the renewed interest as represented by hang gliding takes on particular significance. The big kites represent more than two decades of research, much of it on his own time. In 1963, he and his wife Gertrude received from NASA one of the highest cash awards ever given for an invention. The invention was not an accident at all. It was a purposeful search for a kind of wing that would be less expensive, more rugged, more practical than the conventional kind of wing. And we studied everything along that line that there had already been, like boat sales, windmills, parachutes, and airplane wings before coming up with this design. Experimenting with small gliders and kites, a good performing, completely flexible wing finally evolved in 1948. Ten years later, NASA was searching for devices that could be used to bring astronauts and their spacecraft to a safe landing on Earth. Many versions had many names, paraglider, para-wing, gliding parachute, and flexible wings. The basic design seen in all these can be seen in most hang gliders flying today. Intensive testing ranged all the way from small wind tunnel models to full-scale flight tests complete with man and spacecraft attached. While the Rogalo wing, as it is known by many, has had limited applications, Rogalo himself is optimistic that the new interest generated by some 20,000 fliers worldwide will produce other uses in the future. That's it for this edition of NASA Images. Until next time, this is Lynn Bondrant saying goodbye from the NASA Lewis Research Center in Cleveland, Ohio.