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Old April 30th 07, 10:44 PM posted to rec.aviation.piloting,rec.aviation.student
Jay B
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Posts: 72
Default Sporty's E6B density altitude disparity

On Apr 29, 10:59 am, Tom L. wrote:
I entered the same numbers in my Sporty's E6B and got
PA: 998
DA: 1910

Which is about the same as on the chart.
Your reading of 2000 DA for 1000 PA is slightly off. You need at least
22 deg C for that.

- Tom

On Sun, 29 Apr 2007 17:20:43 GMT, "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?


Here's a sample problem:
Field Elevation: 1165
Altimeter Setting: 30.10
Temperatu 21°C
___________________


Using the standard chart:
http://pacificrimprinting.com/densalt.pdf


30.1 in. Hg Pressure Altitude Conversion Factor: -165
Pressure Altitude: 1000
Density Altitude: 2000
___________________


Sporty's E6B calculation:
Pressure Altitude: 985
Density Altitude: 1894


The Sporty's pressure altitude is off by -15 feet and the density altitude
is off by -106 feet. I can't imagine Sporty's marketing a flawed
E6B, which one is inaccurate?- Hide quoted text -


- Show quoted text -


I got exactly the same...

Jay Beckman
PP-ASEL Lurking
Chandler, AZ