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Contrails is the title for Manifest Episode 111 (Season One, Episode 11). Contrails form when hot humid air from jet exhaust mixes with environmental air of low vapor pressure and low temperature. The mixing is a result of turbulence generated by the engine exhaust.1

Episode References

Contrails of National Air Guard jets which were dispatched to shoot Captain Daly’s plane down  can be seen overhead while Ben and Michaela are on the runway.


Flight 828 experienced turbulence generated when it penetrated a storm mixed with dark lightning. The mixing that occured somhow generated the time continuum. Throughout the episodes of Manifest, a trail of clues has streaked through the scenes of earlier episodes remain visible.  Details (i.e. certain words in the dialogue and objects on the screen) which, at first, were thought to be red herrings pointing our imaginations in different directions or to dead ends, have turned out to be significant.  The further we go into the story the more we appreciate them. These details are like contrails (i.e. breadcrumbs) leading us back to critical points in the story. In future expisodes, we may find ourselves looking back at events and characters with a different perspective and in an entirely different light.


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Contrails (Wikipedia)

Aviaticus cloud
Engine exhaust contrails forming behind an Airbus A340
GenusCirrus (curl of hair), cirrocumulus, or cirrostratus
Altitude7,500 to 12,000 m
(25,000 to 40,000 ft)
ClassificationFamily A (High-level)
Appearancelong bands
Precipitation cloud?No

Contrails (/ˈkɒntrlz/; short for "condensation trails") are line-shaped clouds produced by aircraft engine exhaust or changes in air pressure, typically at aircraft cruise altitudes several miles above the Earth's surface. Contrails 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 that exist at high altitudes allows the formation of the trails. Impurities in the engine exhaust from the fuel, including sulfur compounds (0.05% by weight in jet fuel) provide some of the particles that can serve as sites for water droplet growth in the exhaust and, if water droplets form, they might 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 directly resulting from human activity, are collectively named homogenitus.

Depending on the temperature and humidity at the altitude the contrails form, they may be visible for only a few seconds or minutes, or may persist for hours and spread to be several miles wide, eventually resembling natural cirrus or altocumulus clouds.Persistent contrails are of particular interest to scientists because they increase the cloudiness of the atmosphere. The resulting cloud forms are formally described as homomutatus, and may resemble cirrus, cirrocumulus, or cirrostratus, and are sometimes called cirrus aviaticus. Persistent spreading contrails are suspected to have an effect on global climate.

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