S
WAirbus RACER
WBell 533A
WBell FCX-001
WBuhl A-1 AutogyroB
WEurocopter X³
WKayaba HeliplaneC
WLockheed AH-56 Cheyenne
WLockheed XH-51D
WPiasecki 16H Pathfinder
WPiasecki X-49E
WSikorsky S-72
WSikorsky S-97 RaiderF
WSikorsky X2
WSikorsky–Boeing SB-1 Defiant