So, I finally figured out how to get ATC to say "Lockheed C-130".

This example also uses a military style call sign. The Alphasim C-130 is the aircraft used in this example. I also have Ultimate Traffic for FS 2002 and Edit Voice Pack installed, but this should only effect the word "Hunter".

[fltsim.0]
title=ALPHA C-130 Mk3 Hercules
sim=C-130Hercules
model=CMk3
panel=
sound=
texture=CMk3
atc_id=C3P
atc_airline=Hunter
atc_flight_number=18

atc_parking_types=MIL_CARGO
ui_manufacturer=ALPHA
ui_type=C-130 Hercules
ui_variation=RAF C.3P Hercules
description=© ALPHA Simulations 2003\n\nLockheed C-130 Hercules\n\nThe prototype C-130 first flew in 1954 and the type is still in production nearly 50 years later. The basic design was quite radical for the time but has proven to be a sound platform for numerous conversions such as tanker, rescue, gunship, recon and others. The Herc is a sturdy and reliable workhorse for both military and civilian operators in over 60 countries and continues to be upgraded and improved into the 21st century.


[General]
atc_type=LOCKHEED
atc_model=C130

performance=Model : P Perrott, M Davies\nPanel : P Perrott\nFlight Model : J McDaniel\n\nSpan: 132' 7\nLength: 97' 9\nHeight: 38' 3\nMax T\/O weight: 175,000 lbs\nEmpty weight 75,331 lbs\nMax Cruise Speed: 335 kts\nStall speed: 100 kts\nRate of climb: 1,900 fpm\nService Ceiling: 33,000 ft\nRange with max payload: 2,160 nm\nRange with external fuel: 4,460 nm \nEngines: (4) Allison T56-A-15, 4,508 shp\n\nTake-off run: 3,580 ft\nLanding run: 1,750 ft\n
editable=1


Text highlighted in green must be added to your aircraft.cfg file in the order shown (note the upper case letters), in this case your pilot will report "Hunter 18 is type Lockheed C 130" when first checking in with ATC. ATC will call the aircraft "Hunter 18" for the duration of the flight.
I'm still not sure why FS02 is so picky with the Hercules? Maybe because its a multi engine turbo prop?