American Airlines will launch services on its new Embraer 175s from its Chicago O'Hare hub from 1 August.
The 76-seat regional jets will fly under the American Eagle banner from O'Hare to Albuquerque, New Orleans and Pittsburgh initially, with services expanded to Kansas City, Minneapolis-St Paul, Toronto and Washington National on 27 August, according to a stock exchange filing on Thursday, 11 April 2013.
Services will be expanded to flights between Chicago and Houston Intercontinental, Newark, Philadelphia, Salt Lake City and San Antonio on 1 October.
Republic Airlines will operate 47 E-175s for American under a 12-year capacity purchase agreement that was approved by the bankruptcy court in March. Aircraft will be delivered at a rate of two to three per month from July through the first quarter of 2015.
Fort Worth-based American has said that it needs the small jets to optimise its schedule and fill the gap between its up to 65-seat Bombardier CRJ700s and its 140-seat Boeing MD-80s.
American's proposed merger with US Airways is not expected to impact E-175 operations. Regional jets with 66- to 75-seats are limited to 25% of their combined narrowbody fleet of 810 aircraft, Flightglobal's Ascend Online database shows, under an agreement reached with both airlines' pilots in December.
The limits exclude 76 large regional jets in the US Airways Express fleet currently.
American and US Airways announced their plans to merge on 14 February this year and received bankruptcy court approval on 27 March. The deal still requires approval from US Airways shareholders and US antitrust regulators, which is expected by the third quarter.