exhaust trails

exhaust trails

A cloud that trails an aircraft and is formed by the ejected water from the exhaust of the aircraft engines. It mixes with and saturates, or slightly supersaturates, the air in the wake of the aircraft. The duration of the trails is dependent on the prevailing temperature and relative humidity. Exhaust trails are more common and longer than aerodynamic trails. For the trails to be formed, the temperature ordinarily must be below the critical value as indicated by a line marked MINTRA on a tephigram. A tephigram is an aerological map on which temperatures and potential temperatures (pot) are marked along X- and Y-axes, respectively, and used to ascertain the stability of the atmosphere. MINTRA is a flight level below which exhaust trails will not form positively and above which they may or may not do so. Also called contrails. See also tephigram.
References in periodicals archive ?
Where the exhaust trails were concerned, the report stated that the only reliable means of preventing their formation was to remove the water from engine exhausts by means of a water-recovery system.
Finally, the authors of the NACA report disagreed with a British study's conclusion that "persistent exhaust trails would cease a short distance above the tropopause.
Very faintly on the horizon we could see their shimmering exhaust trails fizzing over the wave tops as they came for us.
More than 40,000 flights by high-flying NATO aircraft released chemically reactive exhaust trails filled with nitrogen oxides that devour stratospheric ozone.
Flying their planes through the exhaust trails of ships, investigators made the first direct measurements of the effect of ship exhaust on cloud droplets.
Designers working on aeronautic projects can create very realistic exhaust trails, missile trails, vapor trails from wingtips, and even skywriting applications.