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Sunday 26 July 2026 · 0241Z EGLL · KJFK · OMDB · VHHH Member log in →
ArticleMay 30, 2026 · 5 min study Members

Hermeus Breaks Sound Barrier with Unmanned Jet at Mach 1.21

Hermeus flew its Quarterhorse Mk 2.1 to Mach 1.21 on 26 May 2026, becoming the first private US company to break the sound barrier.

Hermeus Breaks Sound Barrier with Unmanned Jet at Mach 1.21
FIG. 01 The Hermeus Quarterhorse Mk 2.1 reaches Mach 1.21 on its third test flight over White Sands.Archive

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