Contrails?

Operation Blue Skies - Geoengineering Contrails

The initiative, called Operation Blue Skies, is described as the first large-scale attempt to implement contrail avoidance across an entire controlled airspace rather than through isolated experiments involving individual airlines. The trial will take place over the North Atlantic, specifically the Shanwick Oceanic Control Area—the eastern portion of the heavily traveled corridor between North America and Europe.

The trial is expected to run for 30 months, including operational testing during the winters of 2026–27 and 2027–28. Winter is particularly important because atmospheric conditions over the North Atlantic frequently favor persistent contrails. Approximately 10,000 flights will pass through the relevant Shanwick airspace during trial hours each year, although only a small percentage are expected to require intervention.


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