Hot and high
Hot and high (English: hot and high) is a term used in aviation , of the special atmospheric describes state under these conditions. Both high ambient temperatures and high altitudes lead to a low air density . The influence of these two variables is often converted into a density height that corresponds to the height with the same air density and standard atmosphere .
Take-off and landing under such conditions pose a particular challenge for aircraft , since the lift , which is proportional to the air density, is smaller under otherwise identical boundary conditions. The available engine power also depends on the air density. Under certain circumstances, this can mean that aircraft are not allowed to take off with the otherwise permitted maximum take-off weight ( MTOW ) or require longer take-off and landing distances. Too little power reserve for a sufficient climb over nearby obstacles is the cause of many accidents on airfields in mountain regions.
Even helicopters are limited by these conditions in their flight performance. While airplanes can compensate for thin air during cruise with correspondingly higher speeds, helicopters have to compensate for this effect with higher (continuous) engine power. Such conditions also reduce the payload of helicopters. In addition, the tail rotor can reach its performance limit, which prevents stationary hovering from a certain altitude.
Hot-and-high tests are an integral part of flight testing of new types of aircraft. Frequently approached airports for this purpose are:
- Bole International Airport in Addis Ababa (2334 m above MSL )
- Bogotá Airport (2548 m above MSL)
- El Alto Airport in La Paz (4061 m above MSL)
- Phoenix Airport (335.2 m above MSL, special climatic conditions )
- Aeropuerto Internacional Mariscal Sucre in Quito (2411 m above MSL)
Individual evidence
- ^ A b NOAA: Hot, High and Heavy- The Deadly Cocktail of Density Altitude. (PDF; 2.1 MB) Retrieved February 15, 2013 .
- ↑ pilotfriend.com: Effect of temperature and altitude on airplane performance. Retrieved February 15, 2013 .
- ^ Federal Aviation Administration: Density Altitude. Retrieved April 11, 2014 .
- ↑ International Helicopter Safety Team: Training Fact Sheet - Density Altitude. Retrieved April 11, 2014 .
- ↑ FlightGlobal: A380 arrives in Colombia ahead of hot and high tests. Retrieved February 15, 2013 .
- ↑ FlightGlobal: FLIGHT TEST: Airbus A380. Retrieved February 15, 2013 .