The Field Guide › Paper
Luva and Naweed take a concept borrowed from aviation, the authority gradient (the steepness of the power difference between people who must coordinate, and the way a steep one silences those lower down), and ask what is actually known about it in rail. Their answer is pointed: formal inquiries into major rail accidents repeatedly name an authority gradient between geographically dispersed teams (network controllers, train crews, track workers) as a contributing factor in the communication failures that precede incidents, and yet almost no dedicated research exists to examine, support or refute the claim. The paper is therefore a review and a provocation. It surveys the tools and frameworks used in rail human factors and in other sectors marked by power disparities between teams, draws the explicit parallel to healthcare (where doctors, nurses and allied staff share a goal across steep status differences much as controllers, crews and track workers do), and applies Hofstede's notion of power distance to the rail setting, before identifying the gap itself as the finding: a safety-critical phenomenon that everyone in practice recognises but that research has left largely unstudied. For a corpus about psychological safety this is the concept in one of its oldest and most concrete forms. The authority gradient is the power gradient that psychological safety has to overcome, and the paper is a reminder that steep hierarchy suppresses the speaking-up on which safety depends across whole industries, not just in the cockpit or the operating theatre. Its limit is exactly what it announces: it maps and conceptualises a gap rather than filling it, so it is a strong statement of the problem more than evidence about its size. (Text drawn from the 2021 Theoretical Issues in Ergonomics Science paper.)