Convair 340

Jolted into reality by the large Martin orders, Convair began marketing the improved Model 240A, later renamed the 340, which not only leapfrogged the 404’s attractiveness, but blunted a potential threat from Convair’s East Coast rival.

The Model 340 stretched the 240 design by 4 feet 6 inches, increasing seating capacity to 44 passengers. Its wingspan was lengthened by 13 feet 11 inches, allowing nearly double the 240’s fuel capacity, up to 1,900 gal­lons. Upgraded engines completed the package, which drew a 30-airplane order from United Air Lines, later growing to 55. The Model 340 “Cosmopolitan” enjoyed wide acceptance from the airline industry, both

United flew the largest fleet of Convair-Liners; 55 Model 340s served the carrier for more than 12 years without incurring a single passenger fatality. Mainliner Omaha awaits customers at its San Diego birthplace. (Jon Proctor)
in the United States and overseas. Supplementing the 209 civil versions built, the U. S. Navy and Air Force purchased an additional 102.