Hot, high, and humid days rob your aircraft of performance. Enter your field elevation, the temperature, and the altimeter setting to get your pressure altitude and density altitude — plus a plain-English read on what "thin air" actually means for lift, climb, and your drone's motors.
Density altitude is pressure altitude corrected for temperature — the altitude your aircraft "feels" like it's flying at. When air is hot, high, or humid, it's thinner, so wings make less lift, props and rotors bite less air, and engines and motors make less power. A drone or plane at a 1,000-ft field on a 100°F afternoon can perform as if it's thousands of feet higher.
| Step | Formula (rule of thumb) |
|---|---|
| Pressure altitude | elevation + (29.92 − altimeter) × 1,000 |
| ISA (standard) temp | 15°C − 2°C per 1,000 ft of pressure altitude |
| Density altitude | pressure altitude + 120 × (OAT − ISA temp in °C) |
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