"Ron Natalie" wrote in message
m...
There's no difference in the code numbers for IFR and VFR. What there is
are codes good internal to a facility and external to a facility.

Not exactly sure what you mean by that, but if you mean codes are assigned
willy-nilly regardless of whether the aircraft is VFR or IFR, that's not
entirely true.

Terminal facilities (and maybe centers) split parts of their beacon code
allocation into subsets. The computer is then programmed to perform the
different functions associated with whatever subset a discrete code is in.
For example: In one facility I recall 01XX was used for VFR, 04XX for Local
IFR, and there were a couple others. There were also several sub-subsets
for stuff like VFR w/MSAW or the local traffic/police helicopters.

When you entered the data to generate a track you hit one key for IFR and a
different key for VFR (actually VFR was assumed and no keystroke was
needed). The computer then assigned the next available discrete code from
the appropriate block.

IF a person knows what subset that particular facility has assigned to what
function it's possible to tell a VFR code from an IFR code.