To calculate the Pressure Altitude:
\[ h(\text{alt}) = \left(1 - \left(\frac{P}{1013.25}\right)^{0.190284}\right) \times 145366.45 \]
Where:
Pressure altitude is the altitude of an aircraft above a specific pressure level, typically 29.92 inches of mercury (inHg), which is the standard atmospheric pressure at sea level. This measurement provides a standardized reference point that allows pilots to compare altitudes regardless of local atmospheric pressure variations. It is important for aircraft performance calculations and for ensuring safe flight operations.
Let's assume the following measured pressure:
Step 1: Convert the pressure to millibars:
\[ P_{\text{mb}} = 29.92 \times 33.8639 = 1013.25 \text{ mb} \]
Step 2: Use the formula:
\[ h(\text{alt}) = \left(1 - \left(\frac{1013.25}{1013.25}\right)^{0.190284}\right) \times 145366.45 = 0 \]
The pressure altitude is 0 feet.
Let's assume the following measured pressure:
Step 1: Convert the pressure to millibars:
\[ P_{\text{mb}} = 25.00 \times 33.8639 = 846.5975 \text{ mb} \]
Step 2: Use the formula:
\[ h(\text{alt}) = \left(1 - \left(\frac{846.5975}{1013.25}\right)^{0.190284}\right) \times 145366.45 \approx 4,886.45 \]
The pressure altitude is approximately 4,886.45 feet.
