How do you define the standard lapse rate and what part does moisture play in changes to the rate?
For this question, it is vital to know that the lapse rate is defined as the rate at which the temperature changes with an increase in altitude. What your interviewer is looking to hear is that you understand that dry weather conditions produce a lapse rate of 5.5 degrees per 1,000 feet and 2 degrees per 1,000 feet in moist air. Based on those calculations, your interviewer is looking to hear that the standard lapse rate used in calculations of up to 36,000 feet is 3.5 degrees per 1,000 feet. As you answer this question, additionally talk about your knowledge of this rate and how it impacts flight.
"In my work, I define the standard lapse rate as a 3.5 degree F change in temperature for every 1,000 feet of elevation change in flight. In dryer conditions, that change can be more significant and reach up to a 5 degree change every 1,000 feet. In more moist conditions, the change is less at more around 2 degrees F per 1,000 feet in elevation change. The knowledge of the lapse rates has sure changed flights for pilots as the weather now plays a significant part in creating flight plans and a traditional west coast to east coast flight could have very different path depending on the day and the weather."
