Service Quality Control via return period in airline industry

In the airline industry — coping with a highly competitive market and quickly changing scenarios — it is mandatory to continuously monitor the delivered service quality in order to diagnose weakening system components or check the effectiveness of improvement actions. To this aim, the airlines should rely mainly on customer surveys for ‘measuring the significant’, rather than technical internal measurement. Nevertheless the critical hypothesis about homogeneity and the poor scaling properties often pass in silence, making survey data hazardous to analyse and interpret in the short term. In order to overcome these issues: a) the survey is administered to a traceable and experienced customer — the frequent flyer, therefore receiving a more reliable aggregation of collected data; b) a non parametric approach is held to evaluate the chance event of a “satisfied customer”, i.e. a non negative gap contact, with no need to “inflate” the ordinal metric of the evaluation scale used in the survey. Eventually, a control chart is proposed: by routinely collecting negative gap event time, service quality can suitably be monitored via the return period.