"Jim Macklin" wrote in message
news:HxcBg.85464$ZW3.64724@dukeread04...
If the weather is good VMC, they can fly by pilotage at low
altitude. If the weather is IMC, they fly an IFR rules, at
low altitude using instruments.
http://www.af.mil/factsheets/factsheet.asp?id=183
Was that an attempt to answer my question?