Ackermand et al.(2006): Lazulite-bearing metaquartzite of the Itremo Group (Central Madagascar); Scientific significance and economic importance in Proceedings of the Malagasy-German Research Cooperation in Life and Earth sciences, 5-18
The fastest fighter aircraft is the MiG 25, with speeds topping at Mach 3.2 (2,450 mph/4,000 km/h). Pilots were not allowed to go beyond Mach 2.8. Above Mach 2.8, the engines would overheat and burn up.
The Boeing 747 has a cruise speed of 550 miles per hour, which is actually faster than the top speed combat fighters could achieve in World War Two. Both the X-43 and X-15 aircraft are launched from the air by a B-52.