The density of air has significant effects on the aircraft’s performance. As air becomes less dense, it reduces ________, because the propeller is less efficient in thin air.

The density of air has significant effects on the aircraft’s performance. As air becomes less dense, it reduces ________, because the thin air exerts less force on the airfoils.

The standard atmosphere at sea level is a surface temperature of 59 degrees Fahrenheit (°F) or ____________.

The standard atmosphere at sea level is a surface pressure of 29.92 inches of mercury ("Hg) or ______________.

As altitude ______________, atmospheric pressure ______________.

With every 1,000 feet of increase in altitude, the atmospheric pressure decreases ____________.

As pressure ____________, the air becomes ____________ dense.

______________ is a sudden, drastic change in wind speed and/or direction over a very small area. It can subject an aircraft to violent updrafts and downdrafts, as well as abrupt changes to the horizontal movement of the aircraft.

A ______________ front occurs when a warm mass of air advances and replaces a body of colder air. This type of front move slowly, typically 10 to 25 miles per hour (mph).