ABSTRACT
The aircraft maintenance industry is complex consisting of several interrelated human and machine components. In the aircraft industry, 90% of all inspection is visual and is conducted by human inspectors whose reliability is fundamental to an effective maintenance system. The inspection process essentially consists of two important cognitive components – visual search and decision making. Simply defined, the visual search process involves locating defects in a visual search field and the decision making involves deciding on the severity of the identified defect. If visual inspection performance has to be improved it is critical that both visual search and decision making are performed reliably and consistently. However, human inspection tends to be less than 100% reliable. This human element, however, cannot be entirely eliminated because of our superior decision-making ability (Thapa et al., 1996), our ability to adapt to unforeseen events. As it is important that visual inspection be performed effectively, efficiently, and consistently over time, continuing emphasis has been placed on developing interventions to make inspection more reliable and error tolerant, with training being the strategy of choice for improving the performance of aircraft maintenance inspectors. Researchers (Patrick, 1992; Drury et al., 1992; Gramopadhye et al., 1997) have identified the training content, training methods and delivery system as the important components of a well designed training program. However, training for improving the visual inspection skills is generally lacking at
aircraftmaintenance facilities even though its impact on improvingvisual inspection
skills has been well documented (Moll, 1980; FAA, 1991; FAA, 1993; Drury et al., 1995). It has been shown to improve the performance of both novice and experienced inspectors (Weiner, 1975; Drury et al., 1990; Gramopadhye et al., 1995). In particular, the success of off-line training/retraining with feedback suggests that this method can play an important role in aircraft inspection training. However, existing training for inspectors in the aircraft maintenance environ-
ment tends to be mostly on-the-job training (OJT) (Latorella et al., 1992). This method may not be the best one because feedback, so important to training, may be infrequent, unmethodical, and/or delayed. Moreover, in certain instances feedback is economically prohibitive or impractical because of the nature of the task. Since the benefits of feedback in training have been well documented (Weiner, 1975; Gramopadhye et al., 1997), and for other reasons as well, alternatives to OJT are sought. One of themost viable approaches in the aircraft maintenance environment, given its many constraints and requirements, is computer-based training which offers several advantages over traditional training approaches: it is more efficient while at the same time facilitating standardization and supporting distance learning.
With computer technology becoming cheaper, the future has brought in an increased application of advanced technology to training. Instructional technologists have offered numerous technology-based training devices with the promise of improved efficiency and effectiveness over the past couple of decades. Such training devices are being applied to a variety of technical training applications, including computerbased simulation, interactive videodiscs, and other derivatives of computer-based applications and technology-based delivery systems. In the domain of visual inspection, the earliest efforts to use computers for
off-line inspection training were reported by Czaja and Drury (1981), who used keyboard characters to develop a computer simulation of a visual inspection task. Similar simulations have also been used by other researchers to study inspection performance in a laboratory setting. Since these early efforts, Latorella et al. (1992) and Gramopadhye et al. (1993)
have used low fidelity inspection simulators with computer-generated images to develop off-line inspection training programs for inspection tasks. More recently, researchers have studied human performance using computer simulations for printed circuit board inspection with great success. Another domain which has seen the application of advanced technology is the inspection of X-rays for medical practice. Most of the relevant work in using technology in training has focused on
developing low fidelity simulators for running controlled studies in a laboratory environment. However, research efforts need to be extended in order to take full advantage of the current advances in computer technology. Moreover, advanced technology has found limited application for inspection training in the aircraft maintenance environment. The message is clear: we need more examples of advanced technology applied to inspection training.
