Piston - maybe a Lancair IVP - 287 knots
Turboprop - maybe a Lancair IVP with a Propjet conversion - 330 knots
Jet - ????


An F-106 Delta Dart flew 1526 mph over an 11 mile course way back in 1959
http://www.f-106deltadart.com/speedrecord.htm


"O. Sami Saydjari" wrote in message
...
Just out of curiosity, what is the fastest single-engine aircraft
available and how fast does it go? -Sami