NavList:

Before a piece of navigational equipment can be used officially by a commercial aircraft with passengers on board it must be approved by a relevant authority, so it might be easier to look at the approval history rather than looking at particular aircraft.  Although President Reagan said on 16^th Sep 1983 that the GPS System, when completed, would be available for civilian use free of charge, partly as a result of the shooting down of JAL Flt 007 (a 747) on 1^st Sep 1983, the actual system wasn’t completed until some time later.  The first aircraft GPS receiver certified by the US FAA for use under IFR (Instrument Flight Rules) operations was the Garmin GPS155 on 16^th February 1994.  One can assume that it would have begun being used on passenger flights shortly after that but that major airlines, aircraft manufactures, equipment manufacturers, and the FAA would have been conducting trial flights for some months before this.  DaveP