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.
Commercial airlines cruise at approximately 500 - 600 mph. (804.672 kilometre/hour) Additional InformationFighter jet aircraft fly at speeds in the low mach numbers. Mach one is roughly 750 miles per hour, give or take, and military jets can fly at well over a thousand miles per hour. Back in the day (July of 1976), the SR-71 set the jet speed record.