terminal core, necessitated the construction of a peoplemover, which connected the terminal core with the new terminal as well as remote rental and parking lots. Following deregulation and the buildup of the American and United hubs, O'Hare faced increasing delays from the late 1980s onward due to its inefficient runway layout; the airfield had remained unchanged since the addition of its last new runway (4R/22L) in 1971. O'Hare's three pairs of angled runways were meant to allow takeoffs into the wind, but they came at a cost: the various intersecting runways were both dangerous and inefficient. Official reports at the end of the 1990s ranked O'Hare as one of the worst-performing airports in the United States based on the percentage of delayed flights. In 2001, the Chicago Department of Aviation committed to an O'Hare Modernization Plan (OMP). Initially estimated at $6.6 billion, the OMP was to be paid by bonds issued against the increase in the federal passenger facility charge enacted that year and federal airport improvement funds. The modernization plan was approved by the FAA in October 2005 and involved a complete reconfiguration of the airfield. The OMP included the construction of four new runways, lengthening two existing runways, and decommissioning three old runways to provide O'Hare with six parallel runways and two crosswind runways. The OMP was the subject of legal battles, both with suburbs who feared the new layout's noise implications as well as with survivors of persons interred in a cemetery the city proposed to relocate; some of the cases were not resolved until 2011. These issues, plus the reduction in traffic as a result of the 2008 financial crisis, delayed the OMP's completion; construction of the sixth and final parallel runway (9C/27C) began in 2016. Its completion in 2020, along with an extension of runway 9R/27L completed in 2021, concluded the OMP. Expansion In 2018 the city and airlines committed to PhaseI of a new Terminal Area Plan dubbed O'Hare 21. The plan is to build two all-new satellite concourses to the southwest of Concourse C, and to expand Terminals 2 and 5 with additional gates, lounges, and updates to operations all over the airport. (Terminal 5 will have ten new gates in addition to its expanded facilities, plus two additional gates to each accommodate an Airbus A380.) The expansion will enable same-terminal transfers between international and domestic flights, faster connections, improved facilities and technology