The inspection consists of a checklist of 467 items. The checklist is divided into eleven sections, grouped into four major vehicle subsystems and in its typical version normally takes about 3 hours to complete. The check-off procedure consists of inspecting an item and noting its condition (Serviceable, Unserviceable, Missing or On ERO). If the condition is not deemed Serviceable, the user is required to comment on the condition of the item. The VuMan implementation of the task followed this structure more or less exactly, except that the Comment section was implemented as a multiple-choice question rather than a free-form comment (due to the limitations on the input channel). The items in the multiple-choice sets were chosen as representative of the most common faults encountered (based on an interview of maintenance personnel). The current implementation follows this design.
In terms of the maintenance process, the inspection serves as a tool for the mechanic to fill out a comprehensive work order; the work-order notations are used to prioritize the repair work. The work order is used to initiate the ordering of new parts and to track the progress of the repair work.
The framework provided by CGI permits the use of a flexible control structure and allows the implementation of different interaction protocols. The inspection task allows both for user control of the sequence of items visited (through standard browser navigation features) and for the imposition of certain contingencies by the data collection script. For example, indicating that a part is not in operable condition automatically places the user on the comment page for that item. Similarly, the system can be configured to either request explicit confirmation for each item or to step through the inspection list automatically.