Hot and High
During takeoff and landing under such conditions makes this aircraft a particular challenge because of the buoyancy, which is proportional to the air density under the same conditions is smaller. The available engine power also depends on the air density. Even helicopters are limited by these conditions in their flight performance. While aircraft can compensate thin air at cruising altitude thanks to higher speeds, helicopters have to compensate for this effect by a higher (duration) engine performance. For helicopters, the tail rotor can also come to its limits, which prevents a stationary hover above a certain height. This can possibly cause may start with the aircraft not otherwise permissible maximum takeoff weight (MTOW ) or require longer takeoff and landing distances and also helicopters are limited in their payload. At low power reserves for a sufficient climb over obvious obstacles is the cause of many accidents on airfields in mountainous regions.
Hot- and- high- tests are an integral part of the flight testing of new aircraft types. For this purpose, often brought for airfields are: