wore cciartiertia I April 20, 1991. Gulfstream Aerospace Corp. Model G-IV, s/n 1085, N88GA, Aircraft Type Certificate Data Sheet Al2EA. Refer to: PAA APPROVED Gulfatrean Aerospace Corp. (GAO) MANDATORY Aircraft Service Change (ASC) No. 186 subject: COMMUNICATIONS (ATA 23) COCKPIT VOICE RECORDER/AUDIO - IMPROVEMENTS, dated January 1