Originally Posted by
eckhard
It makes sense but there may be a clue in the textual description of the charts, or the introduction to the manual, along the lines of: “whereas interpolation is permitted, extrapolation below minimum temperature or pressure altitude is not allowed. In these cases, use the lowest value on the graph”.
Have a look and let us know.
Thanks for the reply, I have only been given an A4 sheet with the graph so I will dig out the POH