
Tropopause
Tropopause, marks the boundary between the troposphere and
stratosphere, here temperature is generally considered relatively
constant with increasing altitude
Commercial Aircrafts
Commercial aircraft, use the upper reaches of the troposphere.
This allows them to take advantage of the low air density to achieve
higher speeds and lower fuel consumption. In addition, this altitude
is free of intense weather phenomena and birds.
Weather Phenomena
Radiosonde

Military Aircraft / Supersonic Jets
Military flights use the area between the troposphere and the
stratosphere, known as the tropopause. In this layer, the density
is even lower, so their jet engines are at their most efficient.
Noctilucent Clouds

Polar Stratospheric Clouds

Auroras
