Kevin Pratt , you couldn't be more wrong on all accounts. As the story was ORIGINALLY WRITTEN,
http://luxuryfeed.com/pages/5008127-fastest-supersonic-jet-will-unveiled-farnborough
they claimed exactly what I copied and pasted into my comments... "Gulfstream's new G650.. the world's fastest supersonic jet ... 646 miles per hour." You would have known that if you had bothered reading the JustLuxe archives, but no, you had to show the rest of us what a fool you are.
And no, it wasn't the X54 that was grounded in 2003, a flying X54 hasn't even been built yet. You would have known that had YOU read the article. And yes, it was the Concorde that was grounded in 2003 and no, it wasn't because of the sonic boom. Just like I wrote.
Hate to bust your bubble. The nerve of some people...