Unit 3 - Understanding Air - Section B - Aeronautical Applications of Air Density

These flashcards cover key concepts and vocabulary related to the aeronautical applications of air density, focusing on density altitude and its calculations.

Density Altitude

The altitude relative to standard atmospheric conditions at which air density would be equal to the indicated air density at the place of observation.

Pressure Altitude (PA)

The altitude corrected for non-standard atmospheric pressure, where changes in pressure affect aircraft performance.

Outside Air Temperature (OAT)

The temperature of the air outside the aircraft, which influences density altitude calculations.

International Standard Atmosphere (ISA)

A model of how temperature and pressure vary with altitude under average atmospheric conditions.

Standard Day

A day with air pressure of 29.92 inches of mercury and a temperature of 15 degrees Celsius.

Lift

The force that directly opposes the weight of an aircraft and holds the airplane in the air.

Thrust

The force that propels an aircraft forward, created by engines and propellers.

Standard Lapse Rate

The rate at which temperature decreases with an increase in altitude, typically 2 degrees Celsius per 1,000 feet.

Density

The mass of a substance divided by its volume, a measure of how compact a substance is.

Humidity

The amount of water vapor present in the air, which can affect air density.

Coanda Effect

The tendency of a jet of fluid to attach to a convex surface, creating lift under certain conditions.

Magnus Effect

The phenomenon where a spinning object drags air around it, creating regions of high and low pressure that can change its trajectory.

Barometric Pressure

The pressure exerted by the weight of the atmosphere, measured using a barometer.

Calculating Density Altitude

The process of determining density altitude using the equation: DA = PA + [120 (OAT ‒ ISA)].

Air Density

The density of air, which decreases with altitude and changes with temperature and pressure.

Equation for Pressure Altitude

PA = (29.92 – Barometric Pressure)1,000 + Elevation, used to find the current pressure altitude.