hunting: a standalone construct

In rail vehicle dynamics, hunting (hunting oscillation) is a self-excited, sustained swaying-and-yawing oscillation of a railway wheelset that sets in above a critical speed, as the coned wheels repeatedly overcorrect their lateral position on the rails; it limits stable running speed and, left unchecked, can damage track or cause derailment. Wickens's Fundamentals of rail vehicle dynamics analyses the stability limit and the oscillation. The referent is an instability oscillation of a moving vehicle, unrelated to a bell's steady path beyond the word.[1]

Unit

The onset (critical) speed and the oscillation's amplitude and frequency

Recovery means

Not applicable

Measured by

Characterised by the critical hunting speed and the growth of lateral amplitude