Sporty's E6B density altitude disparity

On Apr 29, 1:20 pm, "Dallas" wrote:
My trusty Sporty's Electronic E6B does not agree with the Density Altitude
Chart. My instructor is at a loss to explain the difference. Can anybody
tell me what's going on?

There are lots of ways to calculate density altitude. Most
calculators used by pilots, totally ignore humidity, for example,
which can make the DA off by a thousand feet. Then there's all the
ways of calculating standard temps, by table or other equations. Plus
different calculators might round differently. So it's no surprise
how different they can be.

Want your head to really explode? :-) See below, the most detailed
DA paper I've seen:

http://wahiduddin.net/calc/density_altitude.htm

Cheers, Kev