American Airlines signals service cuts = = = = Tuesday July 1, 3:30 PM EDT = CHICAGO, July 1 (Reuters) - American Airlines on Tuesday signaled that bi= g changes to its service will be coming soon, saying it cannot continue t= o fly all of the same nonstop routes it now runs nor provide the same ser= vice level in unprofitable markets. American, the world's largest airline and a unit of AMR Corp. (AMR), said= in a statement its ongoing infrastructure review includes everything fro= m the performance of key routes to the space it occupies at major airport= s as well as the structure of its Chicago, Dallas/Fort Worth and St. Loui= s hubs. Chief Executive Gerard Arpey also said Fort Worth-based American is looki= ng at the efficiency of its other major facilities including how it assig= ns work at its three U.S. maintenance bases in Fort Worth, Kansas City, M= o., and Tulsa. The airline said the review is also looking at the volume and nature of r= eservations calls that are distributed among its eight U.S. reservations = offices in Cincinnati; Dallas/Fort Worth area (two offices); Hartford, Co= nn.; Honolulu; Raleigh/Durham, N.C.; St. Louis and Tucson, Ariz. = =A92003 Reuters Limited. = Roger EWROPS