I may be wrong on this ~
But I believe - if ya' want "Default" ATC to be able to "correctly" call out your Aircraft , by ID / Tail number and Name
you've got to make sure all the "Entrys" are properly / correctly filled out in the , Aircraft CFG File
as below :
[fltsim.23]
title=PMDG - British Airways (Landor) 747-400
sim=B747-400
model=RR
panel=VC
sound=RR
texture=MCP_British Airways (Landor)
kb_checklists=PMDG747-400_CHECK
atc_id_color=0xffffffff
atc_id=G-NLBE

this area !!
atc_airline=PMDG

this area too
atc_flight_number=2510

this area
ui_manufacturer=BOEING
ui_type=747-400 RR
ui_variation=British Airways (Landor)

probably this area too

ui_typerole=747-400
description=MCP Boeing 747-400
visual_damage=0
atc_heavy=1
LongAntenna=1
LongAntenna2=0
I don't use Default FSX ATC, for I can't stand those computerized voices drives me crazy
maybe somebody else who's more into the ATC thing can advise you better than dumb ol' me !
This is your Captain ~ Speaking ~ I think were Lost somewhere over the Pacific, anybody got a Road Atlas handy
