WeatherQuestion 70 of 100
What are the standard atmospheric conditions used as the reference for aircraft performance at sea level?
a.15 °C (59 °F) and 29.92 inHg
b.0 °C (32 °F) and 30.00 inHg
c.20 °C (68 °F) and 29.92 inHg
d.15 °C (59 °F) and 28.92 inHg
Explanation
The standard atmosphere at sea level is defined as 15 °C, which equals 59 °F, with a pressure of 29.92 inHg, and performance charts are built around that baseline. Density altitude is simply pressure altitude corrected for how far the actual temperature differs from this standard. The other options misstate either the standard temperature or the standard pressure, and a setting of 28.92 inHg would represent a very deep low-pressure system.
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