Shares of Vertical Aerospace Ltd. EVTL, +3.80%, a company specializing in zero-emissions aviation, said Friday that American Airlines AAL, +0.48% has confirmed delivery slots for the first 50 VX4 aircraft of an initial pre-order of up to 250 aircraft, with an option for up to 100 more. “The commitment to pay pre-delivery payments and confirmation of slot reservations for the first 50 aircraft is believed to be the first of its kind for a major airline in the eVTOL industry, and it marks a significant milestone in the partnership between American and Vertical,” the company said in a statement. Vertical Aerospace went public in 2021 via a merger with a special-purpose acquisition corporation, raising the funding needed to get its five-seat VX4 air taxi certified. The VXR can fly four passengers and a pilot more than 100 miles with zero emissions and minimal noise. Shares jumped 10% premarket on the news, but are down 57% in the year to date, while the S&P 500 SPX, -0.84% has fallen 20%.