Northrop akanga achiri asina chivimbo pamusoro fly-by-waya chidhiraivho uye akaramba mechanically-chiratidzo ndege chidhiraivho. The kunoguma ndege, rakavhurwa musi waJanuary 28, 1971, akazivisa kunonyanyisa uremu 40,000 lb (18,144 makirogiramu) uye kunonyanyisa nokukurumidza Mach 2, asi akamutsa shoma kufarira pakati vatorwa vatorwa. The zvikabva ndege (serial nhamba 72-156 mph9) akanga vakatasva pana Hawthorne Fighter musi waApril 4, 1974; ndege yayo yokutanga pana Edwards AFB akauya musi waJune 9 pamwe "Hute" Henry Choute panguva chidhiraivho, kusvika 61 maminitsi kubhururuka yakakwirira 18,000 tsoka uye kunonyanyisa nokukurumidza maawa 610 uye maneuverability.
21 Nyamavhuvhu