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

7. DESIGNING PROCEDURES7.1 OBJECTIVES AND STRUCTURE OF PROCEDURESIn general, execution of tasks can be viewed as the transition between current state (e.g., before enginestart checklist is complete) and target state (engines have been started) in order to achieve the objective.To support the crews in performing the task, flight management must determine what is expected fromthe crew in terms of task performance. A set of different “methods,” (e.g., mandatory procedure,recommended technique, and policies, etc.), are then introduced to aid the pilots in making the transitionfrom current to target state.7.1.1 Objectives of proceduresThe designer must identify and list all the procedure objective(s) before plunging into the details ofprocedure development. He or she must determine, exactly, what the procedure is trying to establish.For example, are checklist procedures designed as an aid for a “dead tired” crew which flies aninternational route? Or, are checklist procedures developed as only a minimal “killer items” list?Although the apparent objective of the checklist is the same (to configure the aircraft properly), theinteraction with either of the two objectives will yield dramatically different checklists.Consider also the following example: Most airline SOPs require that a callout should be made 1000 feetbefore the assigned altitude. The purpose of this callout is to increase crew awareness prior to an event(level-off), that if not conducted properly, may have an adverse effect (altitude deviation). The mostcommon practice is to call out “one thousand to go.” This callout, however, fails to transfer criticalpieces of information which bound the level-off task: the target altitude, the current altitude, and thedirection (climb/descent). The real objective of the task is not just the level-off maneuver, it is also tolevel-off at the assigned altitude. The procedure and callout should therefore include both 16 . Oneairline, in an attempt to curtail altitude violations, dictated the following procedure “PF will verbalizeleaving the altitude 1,000 feet prior to an assigned altitude. Not 'one to go'; rather 'six thousand forseven thousand' or 'flight level three zero zero for two niner zero.”7.1.2 Who is the Target Population?At first, the answer to the above question may seem trivial -- the pilots. But a closer examination willreveal that there are several sub-populations within a company's pilot population. Are the proceduresdesigned for the line pilot who has been flying the same aircraft for 15 years? For the pilot who justtransitioned from a traditional cockpit to a glass cockpit aircraft? For a new hire who occupies the rightseat in a DC-9? Or are they designed according to the capabilities of the seasoned chief-pilot whodesigned them?For example, one airline's current rejected takeoff (RTO) procedure allows the first officer, when actingas PNF, to call for and, when he or she is PF, to conduct the maneuver. This procedure, however, iscurrently being revised. The future RTO procedure for this airline will allow only the captain to performthis maneuver. There were several factors that led the airline to change this procedure. One was thebelief that a new first officer of a widebody is not experienced enough either to perform or call-for thiscomplicated and extremely hazardous maneuver. In this case the company has made a decision to changethe procedure so that it will accommodate the perceived abilities of the lowest proficiency level in the linepilot population.To summarize, the definition of the target population must be developed, tested, and agreed upon prior todesigning the details of a procedure. Once this component of the operating philosophy has beendetermined it must be communicated to all pilots in the company.16 Note that the “thousand to go” callout is also an example of a too general and somewhat ambiguous SOP -- the sameprocedure yields significantly different outcomes (see Section 6.2.3).41