Density error occurs due to which atmospheric condition?

• A. Humidity changes
• B. Non-standard atmospheric condition
• C. Standard atmosphere
• D. No atmospheric change

Answer: (B)

Density error shows up because airspeed indicators assume a specific air density from the standard atmosphere. When the actual atmosphere isn’t standard—temperature, pressure, and humidity all differ from ISA—the air density is not what the instrument expects. That mismatch changes the relationship between measured dynamic pressure and indicated speed, creating density error. So the correct idea is that the error arises from a non-standard atmospheric condition. Standard atmosphere or no atmospheric change would mean the density assumption is valid, so no density error.