United Airlines says it is making the biggest wide-body purchase in U.S. history, buying 100 Boeing 787 Dreamliners as part of a deal worth an estimated $30 billion, The Wall Street Journal reports. Boeing beat out Airbus SE for the deal, which will allow United to swap out its older Boeing 767 and 777 jets, and also includes an option to purchase an additional 100 Dreamliners after the first tranche. Deliveries of the aircraft are expected to begin in 2024. The Dreamliner was previously plagued by a slew of production delays and regulatory issues after employees uncovered minor defects amid scrutiny following two deadly Boeing 737 MAX crashes.