There is a term used in aviation called “hot and high” that describes an air field that is situated at a high altitude as well as having a warm ambient temperature. Hot air is less dense than cold air and higher elevation further reduces the density. It’s two lines on a performance graph that must be checked prior to takeoff.<p>For fixed wing aircraft, this means that your V2 speed (speed where you generate enough lift to begin climbing) is affected and you have to go faster in these conditions. This is overcome during cruise speeds because less air density is required for lift.<p>The story changes for helicopters, however. Because they generate lift via the rotary wings (rotors) only, they need to spin faster to get more air to hit the blade and thus produce lift. There is an upper RPM that it cannot pass due to physical limitations of the rotors assembly, engine, or both. If it gets hot enough, it can literally spin up to full speed and not move.<p>Helicopters freak me out. Fixed wing aircraft degrade to a glider should all power be lost, a helicopter becomes dead weight with deader occupants.