Efficiency
Efficiency panel is a 3 in 1 panel.
If throttle is higher than 2% It shows your planes actual efficiency. It indicates how many mah is needed to fly one km or mile.
If Throttle is below 2% and your plane is descending It indicates the distance you can glide from your actual hight with your actual heading.
If Throttle is below 2% and your plane is climbing It shows an up arrow indicating that you are probably in a thermic.