What is the approximate true airspeed when indicated airspeed is 80 mph at 5000 feet?

To determine the true airspeed based on the indicated airspeed, factors like altitude and temperature must be taken into account. At 5,000 feet, the indicated airspeed tends to be lower than the true airspeed due to a decrease in air density and the effects of temperature variations at higher elevations.

Using the standard atmospheric conditions to make necessary corrections, the approximate true airspeed can be calculated by adjusting the indicated airspeed based on the density altitude. At 5,000 feet, this correction results in a true airspeed that is a bit higher than the indicated airspeed.

The value of 88 mph becomes the correct choice because it reflects a reasonable correction for altitude and assumes that no significant temperature deviations are present to influence this estimation significantly.

In essence, this option accounts for the standard corrections applied to indicated airspeed at a given altitude, highlighting how altitude can impact readings and thus true speed.