Radio navigation systems are available from several eras of the Duke’s history, so users can fly without GPS via a Bendix KNS-81 RNAV system or with the convenience of a Garmin GTN 750 (PMS50 or TDS). Other radio equipment includes KX-155 NAV/COM radios, KLN-90B, GTN 650, KR 87 ADF, KDI 572 DME, GTX 327 Transponder, Century IV Autopilot and a Bendix RDR1150XL Weather Radar.