Cooling system optimization for light diesel helicopters

CRDID (Common Rail Diesel Engine) main advantage is the reduced fuel consumption, the safety and the flight readiness. In fact, diesel fuel is available everywhere and flights to airports just for refueling can be avoided. However, diesel engines are generally heavier than turbo shaft and require cooling. This necessity is particularly important during near stationary operations of the helicopter. If fans are used for the cooling system, the available power is reduced with an increased penalty weight for the installation. For this reason the ejector exhaust system can be successfully used in CRDID powered helicopters. A feasibility study for the installation of a CRDID (Common Rail Diesel Engine) on a common light helicopter (AB 206) is introduced. The total mass available for the CRDID is evaluated starting from fuel consumption and helicopter data. A derivative of an automotive engine can be used for the turbo shaft to CRDID powered plant conversion. The result is that the installation is indeed possible and the payload can be slightly increased in the diesel powered helicopter due to more power available.