"Steven P. McNicoll" wrote:

The US should conform to the ICAO standard in requiring a clearance for VFR
operations in Class C airspace as VFR aircraft are provided separation. A
clearance and separation go hand-in-hand. The ICAO standard should not
require a clearance for VFR operations in Class D airspace as VFR aircraft
are not separated.

I operate out of an airport which is Class D, cut out of a class C
terminal area, with the only movement area being the runway. The tower
we call is a couple of miles away centered in a Class C airport.

Every time I call them (and I only have to call them to get
instructions for the Delta airspace underlying their Charlie), I get a
"remain clear of Charlie airspace" instruction. The end result is the
same as the ICAO standard, isn't it, since U.S. pilots have to obey
traffic control in Charlie airspace?

Rob