Beyond the Bounds of the Human Factors Tool Kit: Computer-Human Interface Design in a Complex System
To achieve the potential of human factors involvement in computer-human interface design, human factors engineers must transition from being isolated specialists to integrated components of the mainstream life-cycle development process. A fundamental obstacle to this transition has been the limitations associated with traditional human factors methods. The search for better methods has resulted in a recent evolution in the human factors tool kit. While this evolution has increased tool kit utility, it is not yet as robust as needed for the development of complex systems. For the past several years the human factor team at Loral Federal Systems Company has been the central focus of system design and development activities for the Tower Control Computer Complex (TCCC). The TCCC will replace most Federal Aviation Administration airport tower cab equipment with advanced workstations and software. At least five limitations have been encountered with the traditional human factors tool kit due to the complexity of the TCCC and the environment in which it will be used. This paper describes these limitations, and the alternatives that have been successfully employed to produce an operationally suitable computer-human interface as part of an integrated life-cycle effort. At the heart of these remedies were the use of a dedicated team of representative end-users and a variety of non-traditional design evaluation techniques, throughout the project life-cycle. Among these techniques was the evaluation of laboratory prototypes using a “hands-off” intellectual review process and electronically supported group-based evaluations.