SR-72: US secret hypersonic jet to allegedly break sound barrier in 2025 | Believed to be a top-secret project of the US Air Force, the SR-72 is touted to reach over 4,000 mph (6,437 kph), making i…::undefined
SR-72: US secret hypersonic jet to allegedly break sound barrier in 2025 | Believed to be a top-secret project of the US Air Force, the SR-72 is touted to reach over 4,000 mph (6,437 kph), making i…::undefined
Then why do we still operate the U2? SR-71 was operated all the way until 1999. Hubble was launched in 1990 so the large mirrors for spy telescopes had to have been in use well before that.