Google and the UK government are collaborating on Operation Blue Skies, a climate-focused aviation trial that will test whether aircraft can be subtly rerouted to minimise contrail formation over the northeastern Atlantic Ocean. Contrails—the white streaks produced by jet engines—trap heat in the atmosphere and account for approximately one-third of the aviation sector's total climate impact, making their reduction a potentially significant environmental opportunity.

The 30-month project will conduct trials over two winter seasons, using air traffic controllers and AI-powered forecasting to identify atmospheric regions where brief altitude changes of up to 2,000 feet could reduce contrail formation. Only 1–5% of the roughly 10,000 flights crossing the trial zone annually will be adjusted, keeping operations within normal parameters. Google is providing machine learning forecasting technology valued at £1.4 million pro bono, whilst the UK government funds over half of the £5 million total budget, with support from UK air navigation provider NATS and academic institutions including Imperial College London and the University of Cambridge.