Stavatti's Mach-4 SM-39 Razor: A bold NGAD-era fighter concept (not in service)
Private Stavatti Aerospace is marketing the SM-39 Razor as a sixth‑generation, Mach 4 air‑dominance/interceptor concept for NGAD, featuring a distinctive triple‑fuselage design, variable‑cycle engines, advanced materials, and multiple configurations (single-seat, two-seat, and unmanned AI-enabled). The design emphasizes extreme speed and internal bays for stealth, but raises questions about radar signature, external stores, and how cockpit control would work with autonomous teammates. It is a concept, not a current Air Force fighter in service under NGAD.