Determine the density altitude given an airport elevation of 5,515 ft, OAT of 30°C, and an altimeter setting of 29.40" Hg.

Determine the density altitude given an airport elevation of 5,515 ft, OAT of 30°C, and an altimeter setting of 29.40" Hg.

• A. 8,000 feet
• B. 8,900 feet
• C. 9,100 feet
• D. 9,500 feet

Answer: (C)

To find the density altitude, first, it is essential to calculate the pressure altitude and then adjust that value for temperature to determine the density altitude. 1. **Pressure Altitude Calculation**: Pressure altitude can be found using the formula: \[ \text{Pressure Altitude} = \text{Airport Elevation} + (Standard Pressure - \text{Current Pressure}) \times 1000 \] The standard atmospheric pressure at sea level is 29.92 inches of mercury (Hg). In this case, the current setting is 29.40 inches of Hg. The difference can be calculated as: \[ \text{Standard Pressure} - \text{Current Pressure} = 29.92 - 29.40 = 0.52 \, \text{inches Hg} \] Converting this difference to feet: \[ 0.52 \, \text{inches} \times 1000 \, \text{ft/inch} \approx 520 \, \text{ft} \] Therefore, the pressure altitude is: \[ \text{Pressure Altitude} = 5,515 \

To find the density altitude, first, it is essential to calculate the pressure altitude and then adjust that value for temperature to determine the density altitude.

1. Pressure Altitude Calculation:

Pressure altitude can be found using the formula:

[

\text{Pressure Altitude} = \text{Airport Elevation} + (Standard Pressure - \text{Current Pressure}) \times 1000

]

The standard atmospheric pressure at sea level is 29.92 inches of mercury (Hg). In this case, the current setting is 29.40 inches of Hg. The difference can be calculated as:

[

\text{Standard Pressure} - \text{Current Pressure} = 29.92 - 29.40 = 0.52 , \text{inches Hg}

]

Converting this difference to feet:

[

0.52 , \text{inches} \times 1000 , \text{ft/inch} \approx 520 , \text{ft}

]

Therefore, the pressure altitude is:

[

\text{Pressure Altitude} = 5,515 \