Diesel-Electric Hybrid Propulsion System Claims Lower Noise, Improved Safety, Half The Emissions

EADS says it plans to present an innovative hybrid helicopter concept at ILA Berlin Airshow 2010. EADS Innovation Works, the corporate research and technology network of EADS, develops diesel-electric hybrid concepts as part of the Group’s research to make helicopters more environmentally friendly. EADS says the highly efficient electrical motors driving the rotors, combined with diesel engines, reduce fuel consumption and emissions by up to 50 percent.

The EADS Innovation Works Eco2Avia research platform will open up new possibilities for cleaner, safer and more quiet helicopter and aviation operations”, says Dr. Jean Botti, Chief Technical Officer (CTO) of EADS. Take-offs and landings are possible  on electrical power alone, resulting in lower noise levels and improved flight safety.

The main components of this patented hybrid system are multiple dieselelectric motor-generator units, a pair of high-performance batteries and a power electronics unit controlling the energy flows for best efficiency. The OPOC (Opposed Piston, Opposed Cylinder) diesel engines offer a fuel economy improvement of up to 30 percent compared to today’s helicopter turbine engines. The OPOC engine’s power output shafts are fitted with advanced, weight-optimised generators delivering electrical current to the power electronics unit. This unit manages the distribution of the electricity to the electrical motors driving the main rotor and the tail rotor, to and from the batteries as well as to the other user systems on the helicopter.

The four independent energy sources of this kind of propulsion system ensure very high levels of flight safety and efficiency. Several different kinds of combustion engines could be integrated into such a hybrid system. The hybrid system architecture allows the main rotor and its electrical drive to be tilted forward during cruise flight. This enables the helicopter’s fuselage to remain at its optimum alignment with the airstream, minimizing aerodynamic drag and thereby reducing the power demand and the fuel consumption.

Since the tail rotor has no mechanical linkage to the main rotor and its power source, it can be turned off at higher speeds. During these flight phases, stability and control as well as balancing of the rotor torque are provided by the aerodynamic properties of the helicopter’s tail fin and rudder.

The model of a concept helicopter, showcased at ILA, exemplifies EADS Innovation Works’ research towards eco-efficient propulsion system solutions for future helicopters. This is one of the projects that are grouped under the name of eCO2avia by EADS Innovation Works.

FMI: www.eads.com