Flight Operations Manual Practice Test

In hot weather, density altitude rises, meaning the air is thinner. That thinning reduces both engine thrust and wing lift for a given airspeed, so the aircraft needs more runway to take off and climbs more slowly. Those performance penalties directly affect safety and operational limits, making them the primary concern when flying in heat. While comfort and fuel burn can be affected and maintenance costs can rise in extreme heat, they are not the central operational constraint like reduced performance is.