I have noticed over the pased 100 hrs flying behind the Skyview that it shows a higher DA calculation than almost all other E6B computers. Not sure about BA or AFS.
I narrowed the error down to only one possibility that I could think of and that is what are they using for humidity being most EFIS units or calculators for that matter do not allow for a Relative Humidity input.
I recieved a responce from Dynon on the matter here.
Dynon Support Offline
Dynon Technical Support
Sorry we never got back to you on this. The answer is that we calculate density altitude using 100% humidity (zero dew point spread).
This is the worst case (highest density altitude) but clearly isn't going to match any other calculation that uses a different baseline or uses the real humidity.
So it appears that the only time the DA calculation from the Skyview is accurate is when I am flying IMC (100% RH). Any other time the actual DA is something less than the Skyview number.
This also effects the TAS calculation by the Skyview.
If you use the E6B that is included in the utilitys section of your Garmin GPS you will notice much lower DA calcuation and a lower TAS calculation.
Interesting after doing some digging I found this.
If you read pages 10-4 to 10-5 you notice the first thing it says under the "Effects of Humidity" is "The preceeding paragraphs are based on the presumtion of perfectly dry air."
I am assuming my garmin uses 0% RH so am I correct that the actual DA and TAS will usually be somewhere between the one calcuated by "Most" E6B calculator and Dynon's calculation?
When I recieve conflicting data from seperate sources it makes me want to know why. Not that one or the other is wrong they may both be right but I want to know what I am looking at.
Maybe I should install a seperate temp probe with a wick and a bottle of water to keep it moist
and then wire that into the Skyview for a more accurate calculation.