H-H according to ICAO is 1 minute. My manual says I need to provide 4 miles which is more than 1 minute. How is this "a bit dodgy" or "bending the rules"?
In Memphis, Fedex and the FAA agreed on different wake turbulence separation criteria after much research. MD-11, A300 and B767 are separated there by only 2.5 miles.
New Wake Separation Standards Boost Capacity at Memphis | Air Transport News: Aviation International News