| Bell (4 models, 87 registered)Bensen (3 models, 37 registered)Boeing (1 models, 6 registered)Hiller (5 models, 104 registered)Hughes (2 models, 71 registered)Kaman (2 models, 41 registered) | Mcdonnell Douglas (1 models, 11 registered)Mil (1 models, 6 registered)Mil Helicopters (1 models, 7 registered)Sikorsky (5 models, 46 registered)Sikorsky-Chicaco Helicopters (1 models, 7 registered) |
