Even with all the money in the world, you might struggle to purchase jets capable of quickness above Mach 0.9. However, some were sold to civilians in the past.
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How titanium helped build the fastest jet ever

The SR 71 flew so fast that normal metals would melt or weaken. Titanium solved that problem. This video explains why this ...
Are you ready for one of the most exciting business jet of all time? The Global 8000 raises the bar for luxury and is officially certified in the US ...
The Global 8000 (1) is the fastest civilian aircraft since the Concorde with an industry-leading top speed of Mach 0.95 and class-leading range of 8,000 nautical miles (NM) The Global 8000 delivers ...