Why we fly in high level 1.5 metres in height, because this is the appropriate height level as part of that constant. If these external factors such as higher than the wind will affect the flight. Flight mode enables a constant.
Why we fly in an elevation of 1.5 meters in height, because this is the right height for constant flying. If higher than external factors such as wind will affect the flight even more. Flight mode make our constant moves are expected.
The reason why we fly in altitude 1.5 meters in altitude, this is because the flight altitude constant. If high more external factors, such as wind, will affect the flight). The flight is expected mode our constant movement.