1. What is Pressure Altitude?

Definition: Pressure altitude is the altitude in the standard atmosphere where the pressure equals the current atmospheric pressure.

Purpose: It's crucial for aircraft performance calculations, density altitude determination, and flight planning.

2. How Does the Calculator Work?

The calculator uses the standard pressure altitude formula:

Where:

• Pressure Altitude — The calculated altitude (feet)
• Indicated Altitude — The altitude shown on your altimeter (feet)
• Altimeter Setting — The current barometric pressure (inches of mercury)
• 29.92 — Standard pressure at sea level (inHg)

Explanation: The formula adjusts your indicated altitude based on how much the current pressure differs from standard pressure.

3. Importance of Pressure Altitude

Details: Pressure altitude is essential for determining aircraft performance, calculating density altitude, and ensuring proper altitude separation between aircraft.

4. Using the Calculator

Tips: Enter your current indicated altitude and the local altimeter setting. The default altimeter setting is 29.92 inHg (standard pressure).

5. Frequently Asked Questions (FAQ)

Q1: Why is pressure altitude important in aviation?
A: It standardizes altitude measurements regardless of local weather conditions, ensuring consistent aircraft performance calculations.

Q2: What's the standard altimeter setting?
A: 29.92 inches of mercury (inHg) or 1013.25 hectopascals (hPa) is the international standard pressure at sea level.

Q3: When would pressure altitude equal indicated altitude?
A: When the altimeter setting is exactly 29.92 inHg, pressure altitude equals indicated altitude.

Q4: How does this relate to density altitude?
A: Pressure altitude is the first step in calculating density altitude, which also considers temperature and humidity.

Q5: Why multiply by 1000 in the formula?
A: This is the standard conversion factor - each 1 inHg difference from 29.92 equals approximately 1000 feet of altitude correction.