5.1: Determinants of Airplane Performance Flashcards
What are the standard temperature and pressure values for sea level?
15C and 29.92 Hg
What effect, if any, does high humidity have on aircraft performance?
It decreases performance
Which factor would tend to increase the density altitude at a given airport?
An increase in ambient temperature.
What effect does high density altitude, as compared to low density altitude, have on propeller efficiency and why?
Efficiency is reduced because the propeller exerts less force at high density altitudes than at low density altitudes.
What effect does high density altitude have on aircraft performance?
It reduces climb performance.
Which combination of atmospheric conditions will reduce aircraft takeoff and climb performance?
High temperature, high relative humidity, and high density altitude.
As air temperature increases, density altitude will
increase.
You have planned a cross-country flight on a warm spring morning. Your course includes a mountain pass, which is at 11,500 feet MSL. The service ceiling of your airplane is 14,000 feet MSL. After checking the local weather report, you are able to calculate the density altitude of the mountain pass as 14,800 feet MSL. Which of the following is the correct action to take?
Replan you journey to avoid the mountain pass.
A pilot and two passengers landed on a 2,100 foot east-west gravel strip with an elevation of 1,800 feet. The temperature is warmer than expected and after computing the density altitude it is determined the takeoff distance over a 50 foot obstacle is 1,980 feet. The airplane is 75 pounds under gross weight. What would be the best choice?
Wait until the temperature decreases, and recalculate the takeoff performance.
If the outside air temperature (OAT) at a given altitude is warmer than standard, the density altitude is
higher than pressure altitude.
