What's the fastest speed (in Mach) that a jet fighter can go?

Question

Two questions actually -- Is it a U.S. plane?

Answer 1

The fastest fighter as of today is the Mig-25 Foxbat. Generally it is limited to Mach 2.8 to prevent engine damage but there have been cases where it has gone to Mach 3.2.The Mig-25's two engines have a problem run running away, occasionally if you throttle back too fast they'll spool up to maximum thrust and the only way to stop that is to cut the fuel flow. The mach 3.2 run happened when a Mig-25 flying over Israel throttled back too quickly and the engines ran away. Radar operators said he hit mach 3.2 before he shut the engines down, when he got back to the Egyptian airfield the engines had to be replaced.

The fastest United States fighter is likely the F-22 or the F-15. I don't know if the top speed of the F-22 is known but it is said to be "faster than Mach 2.42". The F-15 can do a little over mach 2.5.

Answer 2

The Fokker-Wulf 237 goes at mac 5,7

mac as in macaroni.