Van’s RV-9: New Rotax Power - Kitplanes Magazine How do you inject a healthy level of speed, simplicity, and efficiency into an already efficient airframe? Lockwood Aero’s Rotax 916iS firewall-forward package. With a redesigned cowling, a new cooling system, an MT three-blade constant-speed composite propeller, and an optimized center of gravity that allows full utilization of the RV-9’s 100-pound baggage area while remaining within loading limits, the 916iS-powered RV-9 delivers impressive performance. At FL190, it cruises at 190 knots true on 8.5 gph, while at 8500 feet, it achieves 170 knots true.