There are several trajectories of interest for the analysis of horizontal flight efficiency.
Filed Tactical Flight Model, corresponding to the last filed flight plan (see also FTFM )
Current Tactical Flight Model (see CTFM )
Correlated Positions reports for a Flight, i.e., airspace profiles following as much as possible the actual flown trajectory (based on radar positions - see CPR ).
Profiles generated by the CFMU path generation tool.
Shortest Constrained Route. IFPS compliant route (available CDRs open and RAD compliant).
Shortest RAD restrictions applied Route. All CDRs open.
Shortest Unconstrained Route. No RAD applied, all CDRs open.
Direct route. Any portion outside the FPM_AREA is “frozen”, i.e, not generated by the tool.
The comparison between values for different trajectories of the same flight provides indication on the effects of different factors: