Keystone Aircraft Corp., Bristol, PA, formed by name-change from Huff-Daland 8 March 1927. Continued as principal supplier of bombers to Army, including XB-1 Super Cyclops (2 x Packard), XLB-3 (2 x inverted Liberty), LB-5A Pirate (2 x Liberty) and XLB-6 Panther. Army received 10 LB-5, 17 LB-6 and (1929-32) 25 B-4A, 27 B-5A and 39 B-6A, all with Wright or P&W radials. Other types included Navy XNK-1 Pup armed trainer. Pronto 3-seat land/seaplane, Pathfinder 10-passenger biplane. Patrician 19/20-passenger high-wing monoplane and Sign-Carrier with 90-ft lower wing for flashing neon signs and 8-hr endurance. Lost identity on takeover by Curtiss-Wright early 1933.