>Also, planes use engines differently. They basically run flat out for hours, while cars only use peak power when accelerating. This is often said but isn't re

>Also, planes use engines differently. They basically run flat out for hours, while cars only use peak power when accelerating. This is often said but isn't really all that true if you dig in. Most planes have a cruise power setting that is below that used for takeoff, often 65-80%. Further, engine are often de-rated so that max throttle means something like 80% of the engine's max horsepower. Those two factors along with variable pitch props on some planes which act like gears, mean that even planes often cruise at closer to 60% rated engine horse-power rather than 100%.