1978 Walters.  "CB-3000"  1500/3000/500.  Rehabbed by CRE in 1990.  Lockheed operates its own private fire department at its aircraft maintenance/repair facility at Donaldson Center, SC.  Almost every major airport in the U. S. operated one of these huge Walters rigs at some time.  Raleigh-Durham still has their's in service.