Originally Posted by franklin_m

"Any?"

Not true. There's books full of MTRs out there, all over the country, where aircraft are routinely operating well in excess of 250KIAS indicated at 200-400 AGL. I can't think of the last time I've flown one at less than 420 indicated. Altitudes vary by route but it was quite common to fly them at 420 indicated at 200 AGL. Strike-fighters often plan their routes at 480 indicated - 500 feet AGL and below.

https://www.faa.gov/air_traffic/publ...ction_5.html20