SHEL in Aviation

Introduction

The SHEL model / SHEL deals with the analysis of the interaction between system elements that are encoded in macro-areas identified by the acronym SHEL (Software, Hardware, Environment, Liveware) Software refers to the set of rules, procedures, symbols, assigning tasks. Represents all the material legal and regulatory support for the individual or team. For hardware means machines, tools, equipment and materials, i.e. the components "physical" system. Each of us who have a computer at home, know what is the hardware, i.e. the physical part of the machine: the keyboard, the screen, the main memory.

Environment is the environment, where in addition to technical factors and physical factors heavily influence economic, political, and environmental. So, for environment in the broadest sense refers to the climate, meteorology, topography, slopes, but also, in the strict sense, the social environment of work and the physical place of work, with their limitations. Liveware are the operators, defined as the human component of the system, having a personal communication style-relational, cognitive, and emotional.

This model looks at the interactions, including also the interorganizational analysis, which considers that the interactions with the outside organization, such as relations with suppliers of services, information and training. According to the model SHEL, these cards are in constant interaction with each other and such cards never intersect perfectly, because there are unavoidable frictions arising from the interaction itself. It can be reproduced with the chart opposite, which puts the human element (the last L) at the center of the interaction general.

Discussion

The ICAO (International Civil Aviation Organization), the UN agency to issue delegated legislation, that the world body that governs the phenomenon of commercial aviation in the world, currently adopts a model of organizational accident interpretation called SHEL. The abbreviation stands for Software, Hardware, Environment, Liveware, (Central) Liveware, and this model has been defined by Reinhart as "the relationship of human factors with the environment of aviation." This concept originated from the SHEL model, developed by prof. Edwards in 1972 (Reinhart).

With the increase in world trade due to the introduction of the jet occurred, unfortunately, an increase of accidents and the attention of international organizations (ICAO, IATA), through the development of tools and techniques of investigation and opted for the problems human interface with the new machines and the operating environment. The latter, due to different performance characteristics of the aircraft revealed unknown aspects in the operations of aircraft with propellers.

The ergonomic layout of the cockpit became a key element to prevent certain types of errors such as the perception of instrumental indications (the altimeter was phased out three indices) or the manipulation of levers and switches similar but with different functions (Massimo Felici; Karama Kanoun; Alberto Pasquini). The IATA conference in Istanbul, in 1975, saw the participation of leading experts in analysis of accidents and aviation psychology and physiology, who helped direct the attention of the entire world of aviation human factors.

The main cause of the accident pilot error was previously labeled human factor. Among the experts who ...