I was teaching Bernoulli's relationship to lift during a CFI stage check yesterday and came across the topic of airflow flowing faster over the top of the wing (low pressure) than the lower. I was then asked the question as to why. The only thing i could come up with was because the airflow travels a further distances and tries to meet up with the air below the wing. He told me this was correct but again asked why does this happen. I didn't have a clear explanation, and he didn't have a clear answer. He just said he wanted to know if i knew it. I passed the stage check, did a little research and still could not come up with an answer other than a physics equation. Any help?