I know you have all been waiting for an answer to the question that has everyone stumped. Which is the more accurate calculation?
Because we do not fly in standard conditions most of the time, if you follow the grid lines up and over, as a Piper Representative has advised me, you will get the more accurate result, and the correct way to calculate this data according to Piper.
If you look at the chart to convert pressure altitude to density altitude, you will notice it looks a lot like the first part of the Piper performance charts, where we find temperature and altitude. If you follow the Standard Temperature line up on the density altitude chart, you will get pressure altitude, not density altitude. Defeating the whole purpose of what the chart is used for.
The same thing can be said if you follow the STD TEMP line up on the performance chart. As you can see below, using the charts grid line will give you a correction for non standard temperature, which will be the more accurate result.
I hope this has been helpful. Thanks for stopping by.
PHAK Link for more performance information
The page below is from the Jeppesen Multi Engine Handbook
Коментари