On the Design of Flight-Deck Procedures - Intelligent Systems ...

5. FACTORS THAT BEAR ON PROCEDURE DESIGNIn Chapters 1, 2, and 3 we formulated our generic approach to procedure development, modification,and management. This approach provides the user with a theoretical framework that is independent ofany particular aircraft model, airline, or nation. In the following chapters we will show how the FourP's, as constructed in the first three chapters, can be applied to procedure development.In Chapter Five, we discuss those factors, both internal to and external to the cockpit, that affectoperating procedures. In addition, we will confront the issue of pilot technique, and how it fits into,and is compatible with, the Four P's formulation. In Chapters 6 and 7 we detail some of the issuesinvolved in designing and using procedures. Obviously we could not plunge into the details of everyprocedure. Nevertheless, we believe that the procedure designer will be able to identify themes andconcepts in our formulation, and apply them 6 .5.1. PROCEDURAL DEVELOPMENT BY AIRFRAME MANUFACTURERIn the past, airlines have criticized the airframe manufacturers for designing new procedures for newaircraft without sufficient consideration of the unique operational environment in which airlines “live.”In developing a new aircraft, one airframe manufacturer has taken steps to bridge this gap. The airframemanufacturer stated that it tries to target its procedure more toward Part 121 operators, whileacknowledging the differences in operational environment between airlines that may affect proceduraldesign and flow. For example, different carriers provide manifest, gross weight, zero fuel weight, andtrim information at different times in the ground phase of the flight. This has considerable bearing ondesigning the procedures for this phase, as many tasks are dependent on this information. Themanufacturer has to take these differences into account in designing the flow of tasks in the cockpit.As a conceptual framework for designing procedures for its new aircraft, the airframe manufacturer nowattempts to design the new procedures based on its previous glass cockpits designs. In developing theprocedures, the design team included instructors from the manufacturer's customer training department.This was designed to achieve a significant level of procedural standardization between the previousaircraft and the new aircraft in order to facilitate positive transfer. Another goal was to standardizeterminology. For example, the MCP button that engages the power setting for takeoff and climb hasdifferent names depending on the type of engines used (N1 for CFM engines and EPR for Pratt andWhitney). In the new aircraft, the design team decided to call the button according to its function --Climb Power. Although the engineers who designed the system labeled the button “Thrust,” theinstructors felt that line pilots would find the label “Climb Power” more appropriate for the task. Inessence, the instructors on the design team performed a valuable transformation process betweenengineers who design the systems and the target population -- line pilots, who must use these systems.5.2 WHAT PROMPTS A PROCEDURE CHANGE?Before considering the process of procedural changes by the airlines, we had to explore just what events,internal or external to the cockpit, might prompt a carrier to make changes in procedures. We wereastonished at the great variety of events or conditions that could trigger procedure changes. These eventinclude changes in procedures due to straight forward triggers such as new equipment, new maintenancedata, new routes, and many more. In addition, these events included changes that at first seem remotefrom the cockpit, such as labor relations, marketing influence, new cabin regulations, etc. Seventeen ofthese categories, each with a brief example, are listed in Appendix 6.6 The authors must point out that the Four P's formulation, the concepts, and the guidelines presented in this report werenot the result of an experiment. They were based on interviews, observations, examination of incidents and accidents, andour analysis of the problem. The reader should understand that we have not "proven" the case for our approach.17