We did recently receive some performance data for an airline that used to operate at high-altitude airfields, and it appears that they had specific performance data for every high-altitude airport they operated at. I.e. there isn't a single graph that covers all airfield elevations from 0ft to 12,000ft, they instead used the 0ft to 8,000ft graph to calculate performance in that range, and then had flap 0 (dry), flaps 0 (wet), etc. performance tables for every airport they operated at above 8,000ft.

With the performance data being airport-specific (based on runway length, slope, elevation, surrounding terrain, etc), that makes it tricky to implement the data into the performance calculator without extensively extrapolating the data (which would come at the cost of accuracy).

We do plan on looking into this further once we implement the more powerful Tay 650 engines, which have different performance data.

Mark - Just Flight