This report introduces a number of transitory steps necessary to progress towards the production of enhanced flight efficiency indicators. Three issues were addressed. The first was the replication of existing indicators to test their sensitivity to different assumptions and to the evolution of measurement tools. The second was the compilation of results for airport pairs, and a classification that will ease an efficient selection of airport pair candidates to be studied in detail in future steps of the study. The third was the investigation into the unit costs to use for pricing different kinds of flight inefficiencies, while taking into account differences in operating cost between aircraft types.

Full report on request.