contrail
Sign in to saveContrails (; short for "condensation trails") or vapour trails are line-shaped clouds produced by aircraft engine exhaust or changes in air pressure, typically at aircraft cruising altitudes several kilometres/miles above the Earth's surface. They are composed primarily of water, in the form of ice crystals. The combination of water vapor in aircraft engine exhaust and the low ambient temperatures at high altitudes cause the trails' formation.
Key facts
- Cloud.name
- Contrails
- Cloud.image location
- File:Jet-contrails-tokyosky-japan-2018.webm
- Cloud.image name
- A jet forming contrails in a blue sky
- Cloud.genus
- Cirrus (curl of hair), cirrocumulus, or cirrostratus
- Cloud.altitude_m
- 7,500 to 12,000
- Cloud.altitude_ft
- 25,000 to 40,000
- Cloud.level
- high
- Cloud.appearance
- Long bands
- Cloud.precipitation
- No
via Wikipedia infobox
Article
8 sectionsContents
- Condensation trails as a result of engine exhaust
- Condensation from decreases in pressure
- Impacts on climate
- Head-on contrails
- Distrails
- See also
- References
- External links
Contrails (; short for "condensation trails") or vapour trails are line-shaped clouds produced by aircraft engine exhaust or changes in air pressure, typically at aircraft cruising altitudes several kilometres/miles above the Earth's surface. They are composed primarily of water, in the form of ice crystals. The combination of water vapor in aircraft engine exhaust and the low ambient temperatures at high altitudes cause the trails' formation.
Impurities in the engine exhaust from the fuel, including soot and sulfur compounds (0.05% by weight in jet fuel) provide some of the particles that serve as cloud condensation nuclei for water droplet growth in the exhaust. If water droplets form, they can freeze to form ice particles that compose a contrail. Their formation can also be triggered by changes in air pressure in wingtip vortices, or in the air over the entire wing surface. Contrails, and other clouds caused directly by human activity, are called homogenitus.