The advent of computerization and automation in the cockpits of commercial airliners allowed the airlines to reap a wide variety of benefits. In addition to fuel-efficient flight profiles, more reliable equipment and greater flexibility for upgrades, airlines were able to certify even large, wide-body airplanes like the 767 and the 747400 for operation with only two pilots. The switch initially encountered fierce opposition from airline pilots' unions, but it had great appeal to airline operators because of the cost savings involved. The crew reduction was approved by the FAA, however, after a presidential task force formed to study the subject[Ref 3-34] concluded it posed no safety threat, primarily because the EICAS technology automated many of the functions previously delegated to the third crew member. [Ref 3-35]

Close-up of the Sperry Flight Systems Control and Display Unit (CDU). These were the least user friendly elements in the new computerized "glass cockpit," and caused a number of unanticipated problems when the equipment was put into commericial use.

The new cockpit technology also caused some unanticipated problems, however, illustrating the fact that technical advances are not always a simple forward movement. Technology can sometimes cause new problems even as it solves old ones.

Researchers in NASA, academia and industry all recognized that the new cockpit technology and automation could cause some problems, especially with regard to the role of the pilot and pilot-machine interfaces. For the first time, human factors became an integral part of design analysis, and researchers looked closely at optimum levels of pilot workload and ways to keep pilots involved involved in the computerized systems. Delmar Fadden's flight deck technology group at Boeing, for example, was formed specifically to look at the human performance aspects of the 767's new cockpit technology. [Ref 3-36]

The researchers' main concern was that the automated systems would cause the pilots' workload to become too low, and the pilots would be too far out of the control loop. After the 757 and 767 had been in operation for a few years, however, pilots began complaining that far from being too low, their work load was actually too high. The main culprit was the control and display unit (CDU), which was the pilot interface with the flight management system. [Ref 3-37]

The Sperry Flight Systems CDU consisted of a complete alphanumeric keyboard with 15 additional "mode" keys and a series of "select" keys on either side of a small CRT screen that displayed navigation and performance data, all on 5.75" x 9" unit.[Ref 3-38] As early as 1977, researchers acknowledged that the CDU was designed for "navigation, not for man-machine communication,"[Ref 3-39] but it was the best technology available at the time. The unit was difficult to operate because every command or piece of information had to be typed into the computer with a specific sequence and coding that was difficult to remember.[Ref 3-40] When pilots tried to input new commands during phases of flight that were particularly demanding, such as during approaches or immediately following departure, they were finding themselves overloaded. Sometimes both pilots would get engrossed in trying to operate the computer, leaving nobody looking outside the windows for possible conflicting traffic.

The problems caught the engineers who had researched the technology and designed the systems by surprise. NASA and Boeing engineers concluded they had "underestimated how aggressive pilot crews would be in trying to use the flight management equipment." Gradually, airline training programs began to teach pilots not to use the flight management computer at altitudes under 10,000 feet, but to hand-fly the airplane instead. Second and third generation CDUs are also somewhat simplified, but the problem still exists to some extent today.[Ref 3-41]

The experience with the flight management technology taught the researchers at Langley an important lesson about technology application. Computer technology was a new, emerging technology when the TCV program started its experiments with flight management systems and electronic flight displays. Nobody could have guessed how quickly the technology and its use would spread and progress. Now, however, researchers cautioned that "if you put technology in (a cockpit), you'd better know all the ramifications, because pilots will want to use it." [Ref 3-42]

In an effort to improve the manner in which new technology was implemented and to better anticipate the ways pilots would try to use it, NASA developed the Aviation Safety/Automation Program in 1989. The program, which was a joint effort between the Langley Research Center and the NASA Ames Research Center in California, set out to take a second look at the impact of the automation that is coming into cockpits. Then, using advanced concepts flight simulators (ACFS) at Ames and Langley, researchers planned to explore concepts that would lead to more "human centered automation," in which the automation would be designed to assist pilots in their jobs instead of trying to do their jobs for them.

In 1992, NASA also joined with the FAA and the Air Transport Association's Human Factors Task Force to develop a National Plan for Aviation Human Factors. The task force objectives included correcting some of the current deficiencies in automated cockpits, furthering human-centered automation, and encouraging development of advanced displays and controls that are more "user-friendly."[Ref 3-43]

Even with the unanticipated problems that arose with automated cockpits, however, pilots' overall opinions about the technology were favorable, and the enthusiasm for electronic flight displays was very high. Pilots liked the improved situation awareness the displays provided, and according to the National Transportation Safety Board, as of 1993 there had not been a single accident involving an electronic map display-equipped airliner where the pilot became confused as to his location and flew into terrain. In two surveys of 757 pilots conducted by the Ames Research Center in 1986 and 1987, 8590% of the pilots said they considered the "glass cockpit" displays and instruments a "big step forward."[Ref 3-44] Furthermore, all new transport aircraft designs since the Boeing 767 and some new models of existing airplanes, including the 300, 400 and 500 series of the Boeing 737, incorporated electronic flight displays.

The fact that not all the elements of the electronic flight displays tested in NASA's 737 were used in commercial transport airplanes illustrates the complexity of the technology transfer process. Nevertheless, the aircraft and the TCV program played a very important role in allowing CRT displays to be incorporated into aircraft designs as early as they were. In a June 6 1979 letter to John Reeder, who was then the chief of the TCV program at Langley, the Boeing Commercial Airplane Company's vice president of engineering, Mr. H. W. Withington, described the contributions the Langley research program had made to the development and acceptance of electronic flight displays.

Withington noted that the instruments "were expected to contribute to both the safety and efficiency of flight through a better comprehension by the pilot of the airplane's situation relative to its environment," and he credited the TCV program with the development of several specific aspects of the displays, including the EHSI format and symbology. But the program's most significant contribution, he concluded, was that it "provided the vehicle to bring electronic vertical and horizontal cockpit display instruments from the laboratory to industry acceptance" by demonstrating the technologies to the point "where both the aircraft manufacturer and the user had sufficient confidence to incorporate them into the new airplanes."[Ref 3-45]

In other words, had the TCV program research been conducted in simulators and disseminated only through technical reports and conferences, the Boeing 767 and 757 might very well have been built with conventional flight instruments. Certainly, there were other factors involved. If the displays had proved cost-prohibitive to include, for example, the discussion would have gone no further. As it was, the technology still had to gain the confidence and acceptance of Boeing and the airline industry against concerns over any new cockpit technology and the lack of a clear, quantifiable cost advantage to using the displays. The TCV program's close working relationship with rising young engineers at Boeing, and the fact that the program had an actual transport airplane with which to test and demonstrate the technology, allowed electronic flight displays to gain that acceptance.

Time exposure of the NASA 737 on the ramp at Orlando, Florida.